Monday, April 12, 2021

Improving the Predictive Value of Prion Inactivation Validation Methods to Minimize the Risks of Iatrogenic Transmission With Medical Instruments

Improving the Predictive Value of Prion Inactivation Validation Methods to Minimize the Risks of Iatrogenic Transmission With Medical Instruments

Mohammed Moudjou1, Johan Castille2, Bruno Passet2, Laetitia Herzog1, Fabienne Reine1, Jean-Luc Vilotte2, Human Rezaei1, Vincent Béringue1 and Angélique Igel-Egalon1,3*

1Université Paris Saclay, INRAE, UVSQ, VIM, Jouy-en-Josas, France 2Université Paris Saclay, INRAE, AgroParisTech, GABI, Jouy-en-Josas, France 3FB.INT’L, Montigny-le-Bretonneux, France

Prions are pathogenic infectious agents responsible for fatal, incurable neurodegenerative diseases in animals and humans. Prions are composed exclusively of an aggregated and misfolded form (PrPSc) of the cellular prion protein (PrPC). During the propagation of the disease, PrPSc recruits and misfolds PrPC into further PrPSc. In human, iatrogenic prion transmission has occurred with incompletely sterilized medical material because of the unusual resistance of prions to inactivation. Most commercial prion disinfectants validated against the historical, well-characterized laboratory strain of 263K hamster prions were recently shown to be ineffective against variant Creutzfeldt-Jakob disease human prions. These observations and previous reports support the view that any inactivation method must be validated against the prions for which they are intended to be used. Strain-specific variations in PrPSc physico-chemical properties and conformation are likely to explain the strain-specific efficacy of inactivation methods. Animal bioassays have long been used as gold standards to validate prion inactivation methods, by measuring reduction of prion infectivity. Cell-free assays such as the real-time quaking-induced conversion (RT-QuIC) assay and the protein misfolding cyclic amplification (PMCA) assay have emerged as attractive alternatives. They exploit the seeding capacities of PrPSc to exponentially amplify minute amounts of prions in biospecimens. European and certain national medicine agencies recently implemented their guidelines for prion inactivation of non-disposable medical material; they encourage or request the use of human prions and cell-free assays to improve the predictive value of the validation methods. In this review, we discuss the methodological and technical issues regarding the choice of (i) the cell-free assay, (ii) the human prion strain type, (iii) the prion-containing biological material. We also introduce a new optimized substrate for high-throughput PMCA amplification of human prions bound on steel wires, as translational model for prion-contaminated instruments.

Introduction Transmissible spongiform encephalopathies (TSE) or prion diseases are fatal, uncurable neurodegenerative diseases affecting animals and humans (Collinge, 2001). TSE include scrapie in sheep and goats, bovine spongiform encephalopathy (BSE), chronic wasting disease in cervids and Creutzfeldt-Jakob disease (CJD) in humans. Intra- and inter-species TSE transmission has recurrently occurred in animals and humans via medical and dietary settings. BSE has occurred as an epidemic in cattle and has propagated in human under the form of variant CJD (vCJD). Other dietary exposure in human includes kuru epidemic among Fore people of Papua New Guinea due to funerary cannibalism. Iatrogenic CJD forms are related to the use of contaminated cadaver-extracted human growth hormone and dura mater or to insufficiently sterilized contaminated brain surgery material. The most common forms of CJD are inherited or sporadic.

Transmissible spongiform encephalopathies are caused by prions. Prions are unconventional pathogens exclusively composed of an aggregated and misfolded form (PrPSc) of the cellular prion protein (PrPC). During the disease pathogenesis, PrPSc recruits PrPC and induces its misfolding into further PrPSc. This replicative self-templating process is at the origin of prion infectious nature (Prusiner, 1982). Biochemically, PrPSc and PrPC properties strongly differ. PrPSc is β-sheet rich, contains a protease-resistant core and is prone to aggregation, while PrPC is α-helix rich, protease-sensitive and monomeric (Colby and Prusiner, 2011).

Susceptible mammals, including laboratory species, stably propagate structurally distinct PrPSc assemblies known as prion strains. Prion strains differ biochemically at the level of PrPSc tertiary and quaternary structures. Phenotypically, prion strains encode unique stereotypical biological traits including the time course to disease, neuropathological features and tropism for specific brain regions or lymphoid organs (Bruce, 2003; Collinge and Clarke, 2007; Beringue et al., 2008b; Weissmann et al., 2011). Co-propagation of strains has been observed, notably in CJD (Cassard et al., 2020) and sheep scrapie (Le Dur et al., 2017; Huor et al., 2019). PrPSc structural polymorphism is mostly considered as between strain polymorphism. However, experimental evidence supports the view for further structural diversity and co-propagation of PrPSc assemblies within specific prion populations and strains (Igel-Egalon et al., 2019a).

While human TSE remain relatively rare, they constitute a critical public health concern. First, the disease incubation period is long, asymptomatic, without impact on most biological constants. Early diagnosis of the disease is lacking. Medical, non-disposable instruments may thus be used on individuals incubating silently the disease and potentially be reused. Second, while prions are neurotropic agents, they can replicate extraneurally at significant levels, markedly increasing the range of medical acts that can transmit the disease iatrogenically. Third, prions are highly resistant to common inactivation methods as compared to viruses or bacteria. Since 1999, the World Health Organization guidelines and their national counterparts recommend procedures, which include immersion of non-disposable surgical instruments in 1M sodium hydroxide (NaOH) or 20,000 ppm sodium hypochlorite (2% NaOCl) for 1h, followed by porous autoclaving at 134°C for 18 min (WHO, 1999; DGS, 2011). To circumvent the limits imposed by these methods (e.g., instrument corrosion), the French Medicine Agency (ANSM), for example, recommend since 2011 a list of commercial methods validated for their efficacy to inactivate prions according to a standardized protocol (Ansm, 2011). The validation studies were exclusively based on the inactivation of laboratory prion strains, including as primary model with short incubation time and high infectivity titer hamster-adapted scrapie 263K (or Sc237) prions (Kimberlin and Walker, 1977), as model relevant to BSE/vCJD, mouse-derived BSE prions (Bruce et al., 1994; Lasmezas et al., 1996) or Fukuoka-1 prions derived from the mouse adaptation of human, inherited Gerstmann-Sträussler-Scheinker (GSS) syndrome (Tateishi et al., 1979) as model relevant to human TSE. The inactivation of these prion strains was primarily tested by measuring residual infectivity in hamster or mouse bioassays. However, prion inactivation efficacy is strain-dependent. For example, sporadic CJD prions were shown to be 100,000-fold more resistant than hamster Sc237 prions to acidic SDS treatment (Peretz et al., 2006). The host species in which the strain is passaged can also impact the final efficacy. For example, cattle BSE prions were >1,000-fold more resistant to acidic SDS treatment than BSE-derived mouse 301V prions (Giles et al., 2008). Extended heating or steam sterilization by autoclaving similarly inactivated prions in a strain-dependent manner, BSE and BSE-derived sources being amongst the most resistant strains (Fernie et al., 2012; Marin-Moreno et al., 2019). Worryingly, most ANSM-validated disinfectants which totally inactivated 263K, mouse-BSE or Fukuoka-1 prions were subsequently shown to partially inactivate human vCJD prions (Belondrade et al., 2016; Bélondrade et al., 2020). Collectively, these observations strongly support the view that any inactivation method must be validated against the prions for which they are intended to be used.

The studies by Belondrade et al. (2016); Bélondrade et al. (2020) suggested that cell-free prion amplification assays may replace animal bioassays to quantify prion inactivation efficacy. The European and French Medicine agencies thus implemented their protocols to validate prion inactivation methods. They encourage or request the use of both human prions (or human-relevant prions) and highly sensitive cell-free prion amplification assays (Ansm, 2018; EMA, 2018). These assays measure prion concentration by limiting dilution titration, based on PrPSc seeding activity. Their sensitivity is equivalent or greater than animal bioassays which are measuring prion infectivity. Yet, they are not routinely used in inactivation methods. In this review, we discuss the methodological and technical issues raised by such implementations, with respect to the choice of the cell-free assay, the human prion strain type and the nature of the prion-containing biological material.

Replacing Animal Bioassays by Cell-Free Assays in Prion Inactivation Methods Measuring prion concentration in a test sample has for long relied on measuring prion infectivity by bioassay in laboratory animals. Prion infectious titer can be obtained by endpoint dilution titration of the sample in bio-indicator animals or by using incubation time values once prion dose response curves have been established (Prusiner et al., 1980, 1982). Surrogately, cell-free assays estimate prion concentration by measuring prion self-converting activity. Among them, two ultrasensitive amplification assays deserve attention to their effectiveness to detect minute amounts of prions: the real-time quacking-induced conversion (RT-QuIC) assay (Atarashi et al., 2008; Wilham et al., 2010) and the protein misfolding cyclic amplification (PMCA) assay (Saborio et al., 2001; Figure 1). In essence a PrPSc-containing sample is mixed with a substrate containing normally folded, monomeric recombinant PrP (RT-QuIC) or brain PrPC (PMCA). The conversion is favored and accelerated by cycles of shaking (RT-QuIC) or sonication (PMCA) and quiescent incubation. In the RT-QuIC assay, the conversion of recombinant PrP into amyloid aggregates is followed in real-time by incorporation of thioflavin T (ThT), an amyloid-sensitive fluorescent dye. In the PMCA assay, the conversion of PrPC into PrPSc is assessed at the end of the reaction by biochemical purification and immunodetection of PrPSc. Both tests reach similar or greater sensitivities than those of the animal bioassays. Both have a wide range of fundamental and applied applications, including TSE diagnostic. Both have benefits and drawbacks that make them complementary techniques in the TSE field, as summarized in Table 1.

The RT-QuIC Assay In the RT-QuIC assay, the ThT-positive amyloid assemblies formed by seeded recombinant PrP are poorly infectious (Groveman et al., 2017; Raymond et al., 2020). Manipulation of prion infectivity is thus limited to the seed, limiting biohazards in routine use of the assay. A limiting aspect of RT-QuIC is the possible self-polymerization of recombinant PrP in the absence of any seed. From a diagnostic viewpoint, RT-QuIC is particularly efficient at amplifying prion sub-infectious doses in sample biopsies from the skin (Orru et al., 2017), olfactory mucosa (Orru et al., 2014), urine, saliva (Henderson et al., 2015), blood (Elder et al., 2013), and CSF (McGuire et al., 2012). The second generation of RT-QuIC specially designed for prion detection in the CSF achieved >95% sensitivity and 100% specificity (Orru et al., 2015a), with a good interlaboratory reproducibility, thus opening new avenue for ante-mortem diagnosis of CJD (Rhoads et al., 2020). CSF-based RT-QuIC is now considered as the most powerful versatile technique for diagnosing CJD. It is recommended by the American Center for Disease Control and Prevention (CDC) since 2018. Following this pioneering work, similar CSF-based assays were successfully developed for other prion-like neurodegenerative diseases linked to protein misfolding. These RT-QuIC assays identify alpha-synuclein (Rossi et al., 2020) and Tau (Kraus et al., 2019; Saijo et al., 2020) seeding activity in CSF of patients with Lewy bodies or Parkinson’s disease and Alzheimer’s disease or frontotemporal lobar degeneration, respectively. Proof of concept has been obtained with TDP-43 in amyotrophic lateral sclerosis and frontotemporal lobar degeneration (Scialò et al., 2020).

Given the analytical sensitivity of the RT-QuIC assay and the clear correlation between seeding activity and infectivity in measuring prion concentration (Wilham et al., 2010), its potential to assess prion inactivation methods was assayed. There were discrepancies between the animal bioassay and the RT-QuIC assay. One disinfectant inactivating all measurable prion infectivity by bioassay was not able to eliminate all seeding activity by RT-QuIC (Hughson et al., 2016). In another study, the seeding activity of human CJD prions bound to stainless steel wires was measurable by RT-QuIC and completely removed after a 2 h-treatment with 1M NaOH (Mori et al., 2016), as expected. The reason for such discrepancies is unclear. Prion inactivation treatment may destroy prion infectivity without affecting all PrP seeding activity, given the high sensitivity of the assay. Alternatively, as the RT-QuIC generates amyloid fibers that are off-pathway to prion infectivity, treatment neutralizing these forms may not necessarily affect prion infectivity per se.

The PMCA Assay As key feature, PMCA mirrors in an accelerated manner the prion replication process (Igel-Egalon et al., 2019b). The reaction products are highly infectious – with infectivity titers equivalent to those found in the brain at the terminal stage of the disease – and contain prions which generally retain the parental seed strain phenotype (Weber et al., 2007; Shikiya and Bartz, 2011; Moudjou et al., 2014). PMCA has been instrumental in identifying co-factors (Deleault et al., 2012a,b; Fernández-Borges et al., 2018), PrP domains (Burke et al., 2020a) or post-translational modifications (Moudjou et al., 2016; Burke et al., 2020b) involved in the prion replication process. It has also been instrumental in studying the diversification of PrPSc assemblies and their dynamic interactions (Igel-Egalon et al., 2019b).

The analytical sensitivities of the PMCA and RT-QuIC assays are generally equivalent. RT-QuIC is the method of choice to quantify the seeding activity of prions responsible for sporadic CJD (notably the most prevalent MM1 subtype), whereas PMCA is more performant at detecting vCJD prions (Moudjou et al., 2014; Camacho et al., 2019). PMCA has been incredibly good at detecting vCJD/BSE prions in blood from asymptomatic carriers, in small and large animal models and in human (Lacroux et al., 2014; Bougard et al., 2016; Concha-Marambio et al., 2016). Yet, the necessity to work with PrPC-containing cell or brain substrate and the absence of real-time detection of the conversion process are major impediments to a diagnostic use. Several laboratories are working at substituting PrPC-containing brain substrate with recombinant PrP (Fernández-Borges et al., 2018; Eraña et al., 2019).

With respect to prion inactivation methods, a strong correlation between animal bioassay and PMCA was found in two compelling studies testing several disinfectants or physical processes on 263K prions or vCJD prions bound on stainless steel wires (Pritzkow et al., 2011; Belondrade et al., 2016; Bélondrade et al., 2020). PMCA thus emerged as a potent tool to evaluate the degree of effectiveness of prion inactivation methods, at least with certain human and laboratory strains.

Finding the Right Prion Strain in the Right Shape to Standardize Prion Inactivation Methods Human Prion Strains The choice of the “right” human prion strain to implement the validation of prion inactivation methods is a conundrum:

1. None of the human prion strains have been studied as deeply as hamster 263K with respect to pathogenesis, infectivity titers and response to inactivating treatments by bioassay;

2. The use and relevance of human prions adapted to wild-type laboratory animals must be studied on a case-by-case basis. For example, mouse-adapted Fukuoka-1 prions were not able to propagate on back-passage to transgenic mice expressing human PrP, suggesting loss of parental CJD transmission characteristics (Giles et al., 2017). Oppositely, sporadic CJD prions propagated in bank voles with little or no species barrier, consistent with potential maintain of CJD transmission characteristics (Nonno et al., 2006). Early transmission studies indicated that non-human primates were susceptible to sporadic and vCJD prions (Gibbs et al., 1968; Lasmézas et al., 1996), providing a potential source of human-like prion infectivity. However, macaque and human PrP sequences differ by nine amino acids, which were shown by transgenic modeling to create a substantial species barrier on transmission of sporadic CJD (Espinosa et al., 2019). Whether macaque-passaged prions retain in fine CJD parental properties remain to be determined. Seminal studies by transgenic modeling indicated that amino acid sequence identity between PrPSc and PrPC usually abrogate the barrier to transmission between species (for review Moreno and Telling, 2017). Human prions did not escape the rule. Sporadic and vCJD prions propagate without species barrier in mice transgenic for human PrP, in the absence of mismatch at polymorphic codon 129 (Bishop et al., 2010; Beringue et al., 2012; Chapuis et al., 2016; Jaumain et al., 2016; Cassard et al., 2020). These models, – in the absence of cell models propagating human prions –, allow a relatively rapid, inexpensive, and large production of potentially biologically cloned and well-characterized humanized prions with respect to pathogenesis, strain type and infectivity titers. Oppositely, sporadic and vCJD reference reagents from the World Health Organization contain mixture of strains (Minor et al., 2004; Beringue et al., 2008a; Yull et al., 2009), which may complicate their use in decontamination protocols. It remains to be determined whether humanized prions exhibit similar resistance/sensitivity to inactivation as those that accumulate directly in the human brain. At least, they seem to share similar levels of infectivity (Beringue et al., 2008a; Halliez et al., 2014);

3. The pros and cons of assaying (human or humanized) sporadic or vCJD prions in inactivation trials must be weighed. While the number of clinical cases of vCJD has remained limited (∼235 cases worldwide), this disease is a key issue due to the large number of potential asymptomatic carriers (Gill et al., 2020), the large distribution of infectivity in the body (Douet et al., 2017) and the associated risks of secondary transmission, notably by blood transfusion or surgery (Peden et al., 2004). The disease is due to a unique prion strain type (classical BSE prions) (Diack et al., 2012). When testing heat sterilization methods, BSE/vCJD prions thermostability may increase the predictive value of the assay (Fernie et al., 2012; Marin-Moreno et al., 2019). Sporadic forms of CJD are more prevalent with approximately 1.5 cases per millions per year. The disease is heterogeneous, making the choice of the “right” strain a dilemma; nine sub-types of sporadic CJD are described according to the clinical and neuropathological characteristics of the disease in infected individuals, the polymorphism of the PRNP gene at codon 129 (MM, MV, or VV) and the electrophoretic profile of brain PrPSc (type 1 or type 2) (for review Zerr and Parchi, 2018). At least six distinct strain types are described according to their transmission properties in transgenic mice expressing human PrP. Starting from the most prevalent cases in the population, these strains are classified as MM1/MV1, VV2, MV2, VV1, cortical-MM2, thalamic-MM2 strains (Bishop et al., 2010; Moda et al., 2012; Chapuis et al., 2016; Jaumain et al., 2016; Cassard et al., 2020). Co-propagation of MM1 and VV2 strains has been observed in a significant proportion of sporadic CJD patients (Cassard et al., 2020).

Although direct assay of human prions in inactivation methods may sound highly relevant with respect to iatrogenic risk of prion transmission, it necessitates a thorough examination to ensure that the results obtained are of added value and that extrapolation to the human situation can be made.

Stainless Steel Wires as Model for Surgery Instruments Prions and bacterial biofilms are a challenge to proper sterilization of non-disposable medical devices because of their high resistance to inactivation and binding affinity for steel surfaces. To date, six cases of iatrogenic CJD have been reported worldwide by contaminated surgical instruments or depth EEG electrodes (for review Bonda et al., 2016). Prion-contaminated stainless steel wires have become the gold standard to screen and validate prion inactivation methods for medical instruments. This translational model, which is used in most guidelines, came from the seminal work of Charles Weissmann and collaborators (Zobeley et al., 1999; Flechsig et al., 2001). In essence, wires are artificially contaminated in prion-containing brain macerates. To measure prion concentration pre- and post-disinfection, the wires are permanently implanted in the brain of bio-indicator animals and reduction in the disease attack rate is measured. The reduction factor is established by comparing the results obtained with endpoint titration of prions bound on steel wires. A prion-cell endpoint assay (Klohn et al., 2003) was adapted that offered greater sensitivity, practicability and rapidity than the animal bioassay (Edgeworth et al., 2009). However, its use is so far limited to mouse prions. A sensitive assay based on direct immunodetection of surface-bound prions was also reported and validated against human vCJD prions (Edgeworth et al., 2011b).

Key issues in the interpretation and overall validity of the results are the rate of prion adsorption, desorption and/or bio-activity (i.e., ability to initiate infection in the brain). With mouse or hamster prions, a contact of a few minutes between the infected brain homogenate and the wire was sufficient to transmit the disease with 100% attack rate (Flechsig et al., 2001; Giles et al., 2017). A transient insertion of contaminated wires in the brain for 5–30 min was sufficient to transmit the disease to laboratory animals with 100% attack rate, yet with delayed disease tempo (Flechsig et al., 2001; Yan et al., 2004). This suggested relatively rapid rate of adsorption and release/bio-activity. The information on prion fate once surface-adsorbed is relatively limited. Binding to soil fractions (montmorillonite) was reported to potentiate the disease transmission capacity of hamster 263K prions by oral route (Johnson et al., 2007). The opposite was found on binding to silty clay upon intracerebral inoculation (Saunders et al., 2011). In “standard” conditions, wires are contaminated for 1 h and permanently inserted in bio-indicator animals. To further circumvent these uncertainties and address the possibility that the decontamination procedures unbound prions from the wires without inactivating them, an additional study on the inactivation potential of the method on desorbed material may be requested (Ansm, 2011, 2018).

Heterogeneity of Prion Assemblies The brain tissue does not represent the more likely source of iatrogenic prion contamination, except during neurosurgical procedures. The use of sensitive animal bioassays with human PrP transgenic mice and/or cell-free assays allowed demonstrating that many tissues outside the brain contain substantial amounts of prions, thus markedly increasing the range of medical acts with non-disposable equipment that may transmit human TSE iatrogenically. This includes dentistry, organ transplant, blood transfusion, and surgery. In individuals infected with vCJD, at the symptomatic or pre-symptomatic stage, prions have been detected in a wider and more unexpected variety of peripheral tissues (Douet et al., 2017) than previously reported (Wadsworth et al., 2001). Those include bone marrow, kidney, salivary glands, skeletal muscle, pancreas, liver or heart in addition to tissue of the lymphoid system. In sporadic CJD, while prion distribution is more intense in the central and peripheral nervous systems, substantial amounts of prions have been found in the bone marrow (Huor et al., 2017), skin (Orru et al., 2017), kidney, lung, liver, adrenal glands (Takatsuki et al., 2016), and muscle (Peden et al., 2006; Rubenstein and Chang, 2013). Prions were also detected in biological fluids, notably blood, and urine of patients with sporadic and variant of CJD, often well before the onset of early clinical signs (Edgeworth et al., 2011a; Lacroux et al., 2014; Moda et al., 2014; Sawyer et al., 2015; Luk et al., 2016). Confirmed cases of iatrogenic transmission of vCJD by blood transfusion, and a probable case in a patient treated with coagulation factors VIII manufactured from plasma indicate that blood constitutes an effective source of iatrogenic contamination (Peden et al., 2004, 2010; Wroe et al., 2006). It was reported that the prion protein PrPC is a major contaminant of the purified urinary-derived gonadotropins used in infertility treatment (Van Dorsselaer et al., 2011). These elements raise specifically the question of prion biosafety of blood, blood-derived products, and urine-derived drug products. Analytical technics for securing drug manufacturing process from blood and urine must be reconsidered and implemented as those securing medical instrumentation, as recently recommended by the European Medicines Agency (EMA, 2018).

Prion presence in several tissues and bodily fluids raises the question of the most physiologically relevant PrPSc aggregates and of the best experimental approach for their inactivation. Most studies use brain macerates or microsomal brain fractions to contaminate steel wires or as spike for studying prion removal. Their high infectious titer compared to other extraneural tissues or fluids obviously increases the analytical sensitivity of the approach. However, PrPSc assemblies in bodily fluids or extraneural tissue may be of smaller size than in the brain. Compelling evidence indicate that different subassemblies with specific structural properties are co-accumulating in the brain at the disease terminal stage. These sub-assemblies harbor different size, different infectivity titer or seeding activity (for review Igel-Egalon et al., 2019a). Their capacity to bind steel wires or their retention properties may vary.

Further, the preparation of the spike or of the dilutions in the ad hoc experimental conditions may modify PrPSc assembly composition. In our previous work, we demonstrated that PrPSc assemblies have two levels of organization (Igel-Egalon et al., 2017). The first one is formed by the packing of oligomeric building blocks (called suPrP) into larger assemblies. In this organization, the cohesion forces are weak, as shown that rapid depolymerization following urea chaotropic treatment. The second level of organization is formed by suPrP itself. suPrP is a very stable oligomer between a dimer or a tetramer that resists >6–8 M urea. This study led us to conclude that PrPSc assemblies and their building blocks are in a highly dynamic equilibrium (Igel-Egalon et al., 2017, 2019a). A simple dilution of purified PrPSc assemblies was able to drive the equilibrium towards their depolymerization into suPrP. A dilution process may thus drive which PrPSc morphotype is submitted to the inactivation/retention process; in return PrPSc morphotype are likely to react to such process in a structural-dependent manner. To conciliate the advantage of using brain extract with the relevance of the model, one alternative could be the use of small PrPSc particles, obtained by fractionation experiments. We previously demonstrated that these assemblies have high specific infectivity values despite their small size (Tixador et al., 2010; Laferriere et al., 2013) and are relatively stable over time out of the conversion process (Igel-Egalon et al., 2019b).

As for the nature of the prion strain, these data collectively support the view that the retention/inactivation methods must be validated against the biological material for which they are intended to be used.

Human Prion PMCA PMCA Improvements and Putative Mechanisms of Prion Amplification Efficient amplification of human prions by PMCA is strain dependent. It was initially believed that optimal amplification of human prion strains required absence of mismatch at codon 129 between the seed and the substrate. Thus, Jones et al. (2009) classified CJD subtypes in two distinct groups according to their “preference” for the PRNP genotype substrate. The first group, composed of vCJD, MM1, MM2, and MV1 sporadic prions, is preferentially amplified by the PRNP-129MM substrate. The second one, composed of VV1, VV2, and MV2 sporadic CJD prions, is more efficiently amplified by PRNP-129VV substrate. Despite this sequence compatibility, prions were not amplified to a degree of sensitivity sufficient for validating decontamination methods.

Other parameters can be adjusted to improve PMCA efficacy: (1) Obviously, the number of PMCA rounds can be increased. While it was initially suspected to increase the probability of de novo PrPSc formation in the absence of preexisting prions, carefully designed PMCA operating conditions suggested that spontaneous prion formation in PMCA reactions was rather a result of inadvertent cross-contamination (Cosseddu et al., 2011). Three to six rounds of PMCA are routinely used to amplify low amounts of human prions (Lacroux et al., 2014; Bougard et al., 2016; Concha-Marambio et al., 2016; Cassard et al., 2020); (2) The PrPC substrate can be optimized. The higher the PrPC concentration, the higher the sensitivity achieved (Mays et al., 2009; Moudjou et al., 2014, 2016), which lends support for the use of brain from transgenic mice overexpressing PrPC. Further, markedly improved sensitivities, including with human prions, were obtained when PMCA was performed with partially desialylated (Katorcha et al., 2015) or unglycosylated PrPC (Nishina et al., 2006; Camacho et al., 2019) as substrate. The authors attribute this phenomenon to sialic acid electrostatic repulsion forces and the glycan steric hindrance that may interfere with the conversion of PrPC by PrPSc. Whether this would work with all strains given their variable glycoform requirements (Khalili-Shirazi et al., 2005; Nishina et al., 2006) remains to be determined; (3) Conversion enhancers can be added to the PMCA reaction, including polyanions (Fernández-Borges et al., 2018), anionic lipids (Deleault et al., 2007), or dextran sulfate (Moudjou et al., 2016). Their mode of action on the conversion process remains poorly understood. Their impact on ionic strength, osmolarity, water molecule organization, PrPC or assemblies stability may play a role in the replication/templating process; (4) Physical change in the PMCA environment such as the reaction volume or the addition of microbeads in the substrate affected significantly the amplification efficacy with respect to the dilution achieved (Gonzalez-Montalban et al., 2011; Johnson et al., 2012; Moudjou et al., 2014).

The commonly shared view that microbeads addition increases the fragmentation of the newly converted PrPSc assemblies during the sonication steps and therefore multiplies the number of templating interface for conversion was recently challenged. By using sedimentation velocity to explore the quaternary structure of prion assemblies, we found no evidence for fragmentation in PMCA conditions with beads (Igel-Egalon et al., 2019b). Alternative hypotheses such as beads serving as thermoacoustic convertor (Povey et al., 2011) and/or as multidirectional secondary source may be considered.

We propose an alternative model to prion fragmentation to explain prion amplification during PMCA, based on the existence of a detailed-balance between PrPSc assemblies and suPrP (Chyba et al., 2020). A perturbation in prion environment would shift the balance towards PrPSc assemblies depolymerization into suPrP, thus multiplying the number of templating interface. We experimentally investigated this by studying the impact on PrPSc assemblies size of diluting infected brain homogenate in PMCA buffer, out of a replicative context and without sonication. As shown in Figures 2A–C, a >1:3 dilution was sufficient to depolymerize PrPSc assemblies into smaller objects, indicating an equilibrium displacement (Figure 2D). This was observed for three different prion strains, suggesting a possible generic effect. This observation supports the view that the physico-chemical properties of the PMCA buffer are enough to disrupt PrPSc assemblies, suggesting therefore that PrPSc fragmentation does not occur during bead-PMCA reactions.

Despite these major improvements, certain prion types remain unamplifiable by PMCA or do not achieve degrees of amplification requested by the medicine agencies (6 Log10 of magnitude (Ansm, 2018)). The MM1 subtype remains the most difficult sporadic CJD subtype to amplify. At variance with RT-QuIC (Orru et al., 2015b), there is no universal PMCA substrate for human CJD prions.

A PMCA Substrate to Amplify With High Sensitivity Human Prion Strains Adsorbed on Steel Surface or in Suspension With all the potential factors improving PMCA sensitivity in mind, we optimized a substrate to amplify human sporadic CJD prions. First, we designed a new transgenic mouse line homozygous at the locus transgene that overexpressed approximately five- to sixfold the valine allele at codon 129 of human PrPC (BacV line) on a pure FVB/N PrP-knockout background (Passet et al., 2020). The transgene designed for targeting expression of human PrP in these mice is based on a large human BAC insert (the details of the transgenic mice will be published elsewhere). The brain of these mice was used as PrPC substrate in PMCA reactions (see Supplementary Material for the methods section). To improve the sensitivity of the reaction, we added polymers of dextran, one teflon microbeads and worked with a reduced reaction volume, as previously described in our so-called mb-PMCA protocol (Moudjou et al., 2014, 2016). As seed, we used brain homogenates from humanized mice in which we isolated and phenotypically characterized different sporadic CJD subtypes (Jaumain et al., 2016). Those were serially diluted and submitted to one to three rounds of mb-PMCA reaction. Humanized MV2, VV1, VV2 sporadic CJD prions, and vCJD prions were used. Positive reactions were obtained for these humanized strain types up to the 10–7 (MV2 subtype) to 10–10 (VV2 subtype) dilution (Figures 3A,B). Noticeably, mismatch at codon 129 between seed and substrate was not detrimental as the highest levels of amplification were observed with sporadic CJD VV2 prions and vCJD prions serially passaged onto transgenic mice expressing human-PrPC with Met at codon 129. The dynamic of amplification obtained with vCJD prions (limiting dilution at 10–9) or VV2 (10–9 or 10–10 depending on the allele on which the subtype was propagated) offered an analytical sensitivity compatible with the validation of prion inactivation methods. In the case of vCJD prions, it was more sensitive than animal bioassays by at least two orders of magnitude (Douet et al., 2014; Halliez et al., 2014).

In the context of the risk evaluation associated with the decontamination of medical instruments, we further evaluated the effectiveness of the BacV-derived mb-PMCA substrate to detect human prions bound onto steel surface. Briefly, fine stainless steel wires were contaminated with serial dilutions of prion-containing brain homogenate (Zobeley et al., 1999; Flechsig et al., 2001) and added directly to the mb-PMCA reaction mix as seed. As summarized in Figures 3C,D, two rounds of PMCA were enough to detect bound prions up to the 10–6–10–7 dilution. Again, these limiting dilution values were in the range required for appraisal of inactivation methods by using steel wire as translational model for medical instruments.

Conclusion

This mini-review addresses the questions raised by the implementations, by the competent authorities, of prionicidal product authorizations. Any validation procedure should be tested against prions for which the inactivant is intended to be used, suggesting that human or humanized prions should be used in fine. However, several pending questions are emerging, including the choice of the prion subtype and of the prion-containing biological matrix. Another operational aspect to consider is the high biohazard level to manipulate these agents as compared to laboratory 263K prions.

Given the correlation between PMCA and animal bioassay in measuring prion concentration bound on steel wires or in suspension, there is a proof of concept that this cell-free assay could complement and even replace animal bioassays. This would provide an economical and ethically sound method. Yet, certain human prion subtypes remain poorly amplifiable, limiting the potential relevance of the assay. Given the high-throughput, rapid format of the assay, the use of several prion subtypes may circumvent this. Animal bioassays using human or humanized prion are still considered as gold standard methods. These models and the PMCA assay are mostly manipulated in academic laboratories and not in Contract Research Organizations (CROs) that routinely perform studies for biocidal products authorizations. This may delay the time to market of these products.


Case Report

Abnormal prion protein deposits with high seeding activities in the skeletal muscle, femoral nerve, and scalp of an autopsied case of sporadic Creutzfeldt–Jakob disease

Hiroyuki Honda Shinichiro Mori Akihiro Watanabe Naokazu Sasagasako Shoko Sadashima Trang Đồng Katsuya Satoh Noriyuki Nishida Toru Iwaki

First published:04 February 2021


Abstract

We report the general autopsy findings of abnormal prion protein (PrP) deposits with their seeding activities, as assessed by the real‐time quaking‐induced conversion (RT‐QuIC) method, in a 72‐year‐old female patient with sporadic Creutzfeldt–Jakob disease (sCJD). At 68 years of age, she presented with gait disturbance and visual disorders. Electroencephalography showed periodic synchronous discharge. Myoclonus was also observed. A genetic test revealed that PRNP codon 129 was methionine/methionine (MM). She died of pneumonia three years and four months after disease onset, and a general autopsy was performed. The brain weighed 650 g and appeared markedly atrophic. Immunohistochemistry for PrP revealed synaptic PrP deposits and coarse PrP deposits in the cerebral cortices, basal ganglia, cerebellum, and brainstem. Western blot analysis identified type 1 proteinase‐K‐resistant PrP in frontal cortex samples. PrP deposits were also observed in systemic organs, including the femoral nerve, psoas major muscle, abdominal skin, adrenal medulla, zona reticularis of the adrenal gland, islet cells of the pancreas, and thyroid gland. The RT‐QuIC method revealed positive seeding activities in all examined organs, including the frontal cortex, femoral nerve, psoas major muscle, scalp, abdominal skin, adrenal gland, pancreas, and thyroid gland. The following 50% seeding dose (SD50) values were 9.5 (frontal cortex); 8 ± 0.53 (femoral nerve); 7 ± 0.53 (psoas major muscle); and 7.88 ± 0.17 (scalp). The SD50 values for the adrenal gland, dermis, pancreas, and thyroid gland were 6.12 ± 0.53, 5.25, 4.75, and 4.5, respectively. PrP deposits in general organs may be associated with long‐term disease duration. This case indicated the necessity for general autopsies in sCJD cases to establish strict infection control procedures for surgical treatment and to examine certain organs.

Figure S1 Histopathological findings and prion protein staining in the peripheral organs. (A, D, G, J, and M) HE staining. (B, E, H, K, and N) Immunohistochemistry staining for prion protein (3F4). (C, F, I, L, and O) Immunohistochemistry staining for prion protein (8G8). (A, B, and C) Hair follicle in the dermis: Hair follicle shows normal appearance (A). A small amount of PrP deposits are noted around the hair follicle (B: arrowhead) and sebaceous gland (*) (B). Immunostaining with 8G8 shows a small amount of PrP deposits around the hair follicle (C: arrowhead). Strong immunopositivity is also observed in the hair follicle (C). (D, E, and F) Eccrine gland in the dermis: Eccrine gland shows normal appearance (D). Faint cytoplasmic PrP staining can be observed (E). Immunostaining with 8G8 shows marked immunopositivity in the eccrine gland (F). (G, H, and I) Zona reticularis in the adrenal gland: The cells of zona reticularis show normal appearance (G). Cytoplasmic PrP staining can be seen (H and I). (J, K, and L) Adrenal medulla: The cells of adrenal medulla show normal appearance (J). Marked cytoplasmic PrP staining can be observed (H). Immunostaining with 8G8 also shows cytoplasmic PrP staining (L). (M, N, and O) Pancreas: Islet cells show normal appearance (M). Faint PrP cytoplasmic staining can be observed in the islet cells (N and O).

Figure S2 (A–F) Immunohistochemistry for prion protein in control case (non‐prion disease). (A, C, and E) Immunohistochemistry staining for prion protein (3F4). (B, D, and F) Immunohistochemistry staining for prion protein (8G8). (A, B) In the zona reticularis of the adrenal gland, cytoplasmic PrP immunostaining is very weak. (C, D) Immunostaining with 3F4 (C) and 8G8 (D) shows weak cytoplasmic PrP staining in the adrenal medulla. (E, F) Immunostaining with 3F4 (E) and 8G8 (F) shows weak cytoplasmic PrP staining in the islet cells.


1: J Neurol Neurosurg Psychiatry 1994 Jun;57(6):757-8 

***> Transmission of Creutzfeldt-Jakob disease to a chimpanzee by electrodes contaminated during neurosurgery. 

Gibbs CJ Jr, Asher DM, Kobrine A, Amyx HL, Sulima MP, Gajdusek DC. 

Laboratory of Central Nervous System Studies, National Institute of 

Neurological Disorders and Stroke, National Institutes of Health, 

Bethesda, MD 20892. 

Stereotactic multicontact electrodes used to probe the cerebral cortex of a middle aged woman with progressive dementia were previously implicated in the accidental transmission of Creutzfeldt-Jakob disease (CJD) to two younger patients. The diagnoses of CJD have been confirmed for all three cases. More than two years after their last use in humans, after three cleanings and repeated sterilisation in ethanol and formaldehyde vapour, the electrodes were implanted in the cortex of a chimpanzee. Eighteen months later the animal became ill with CJD. This finding serves to re-emphasise the potential danger posed by reuse of instruments contaminated with the agents of spongiform encephalopathies, even after scrupulous attempts to clean them. 

PMID: 8006664 [PubMed - indexed for MEDLINE] 


Prion Conference 2018 Abstracts

BSE aka MAD COW DISEASE, was first discovered in 1984, and it took until 1995 to finally admit that BSE was causing nvCJD, the rest there is history, but that science is still evolving i.e. science now shows that indeed atypical L-type BSE, atypical Nor-98 Scrapie, and typical Scrapie are all zoonosis, zoonotic for humans, there from. 

HOW long are we going to wait for Chronic Wasting Disease, CWD TSE Prion of Cervid, and zoonosis, zoonotic tranmission to humans there from?

Studies have shown since 1994 that humans are susceptible to CWD TSE Prion, so, what's the hold up with making CWD a zoonotic zoonosis disease, the iatrogenic transmissions there from is not waiting for someone to make a decision.

Prion Conference 2018 Abstracts

P190 Human prion disease mortality rates by occurrence of chronic wasting disease in freeranging cervids, United States

Abrams JY (1), Maddox RA (1), Schonberger LB (1), Person MK (1), Appleby BS (2), Belay ED (1)

(1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA.

Background

Chronic wasting disease (CWD) is a prion disease of deer and elk that has been identified in freeranging cervids in 23 US states. While there is currently no epidemiological evidence for zoonotic transmission through the consumption of contaminated venison, studies suggest the CWD agent can cross the species barrier in experimental models designed to closely mimic humans. We compared rates of human prion disease in states with and without CWD to examine the possibility of undetermined zoonotic transmission.

Methods

Death records from the National Center for Health Statistics, case records from the National Prion Disease Pathology Surveillance Center, and additional state case reports were combined to create a database of human prion disease cases from 2003-2015. Identification of CWD in each state was determined through reports of positive CWD tests by state wildlife agencies. Age- and race-adjusted mortality rates for human prion disease, excluding cases with known etiology, were determined for four categories of states based on CWD occurrence: highly endemic (>16 counties with CWD identified in free-ranging cervids); moderately endemic (3-10 counties with CWD); low endemic (1-2 counties with CWD); and no CWD states. States were counted as having no CWD until the year CWD was first identified. Analyses stratified by age, sex, and time period were also conducted to focus on subgroups for which zoonotic transmission would be more likely to be detected: cases <55 years old, male sex, and the latter half of the study (2010-2015).

Results

Highly endemic states had a higher rate of prion disease mortality compared to non-CWD states (rate ratio [RR]: 1.12, 95% confidence interval [CI] = 1.01 - 1.23), as did low endemic states (RR: 1.15, 95% CI = 1.04 - 1.27). Moderately endemic states did not have an elevated mortality rate (RR: 1.05, 95% CI = 0.93 - 1.17). In age-stratified analyses, prion disease mortality rates among the <55 year old population were elevated for moderately endemic states (RR: 1.57, 95% CI = 1.10 – 2.24) while mortality rates were elevated among those ≥55 for highly endemic states (RR: 1.13, 95% CI = 1.02 - 1.26) and low endemic states (RR: 1.16, 95% CI = 1.04 - 1.29). In other stratified analyses, prion disease mortality rates for males were only elevated for low endemic states (RR: 1.27, 95% CI = 1.10 - 1.48), and none of the categories of CWD-endemic states had elevated mortality rates for the latter time period (2010-2015).

Conclusions

While higher prion disease mortality rates in certain categories of states with CWD in free-ranging cervids were noted, additional stratified analyses did not reveal markedly elevated rates for potentially sensitive subgroups that would be suggestive of zoonotic transmission. Unknown confounding factors or other biases may explain state-by-state differences in prion disease mortality.

=====

P172 Peripheral Neuropathy in Patients with Prion Disease

Wang H(1), Cohen M(1), Appleby BS(1,2)

(1) University Hospitals Cleveland Medical Center, Cleveland, Ohio (2) National Prion Disease Pathology Surveillance Center, Cleveland, Ohio.

Prion disease is a fatal progressive neurodegenerative disease due to deposition of an abnormal protease-resistant isoform of prion protein. Typical symptoms include rapidly progressive dementia, myoclonus, visual disturbance and hallucinations. Interestingly, in patients with prion disease, the abnormal protein canould also be found in the peripheral nervous system. Case reports of prion deposition in peripheral nerves have been reported. Peripheral nerve involvement is thought to be uncommon; however, little is known about the exact prevalence and features of peripheral neuropathy in patients with prion disease.

We reviewed autopsy-proven prion cases from the National Prion Disease Pathology Surveillance Center that were diagnosed between September 2016 to March 2017. We collected information regarding prion protein diagnosis, demographics, comorbidities, clinical symptoms, physical exam, neuropathology, molecular subtype, genetics lab, brain MRI, image and EMG reports. Our study included 104 patients. Thirteen (12.5%) patients had either subjective symptoms or objective signs of peripheral neuropathy. Among these 13 patients, 3 had other known potential etiologies of peripheral neuropathy such as vitamin B12 deficiency or prior chemotherapy. Among 10 patients that had no other clear etiology, 3 (30%) had familial CJD. The most common sCJD subtype was MV1-2 (30%), followed by MM1-2 (20%). The Majority of cases wasere male (60%). Half of them had exposure to wild game. The most common subjective symptoms were tingling and/or numbness of distal extremities. The most common objective finding was diminished vibratory sensation in the feet. Half of them had an EMG with the findings ranging from fasciculations to axonal polyneuropathy or demyelinating polyneuropathy.

Our study provides an overview of the pattern of peripheral neuropathy in patients with prion disease. Among patients with peripheral neuropathy symptoms or signs, majority has polyneuropathy. It is important to document the baseline frequency of peripheral neuropathy in prion diseases as these symptoms may become important when conducting surveillance for potential novel zoonotic prion diseases.

=====

P177 PrP plaques in methionine homozygous Creutzfeldt-Jakob disease patients as a potential marker of iatrogenic transmission

Abrams JY (1), Schonberger LB (1), Cali I (2), Cohen Y (2), Blevins JE (2), Maddox RA (1), Belay ED (1), Appleby BS (2), Cohen ML (2)

(1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA.

Background

Sporadic Creutzfeldt-Jakob disease (CJD) is widely believed to originate from de novo spontaneous conversion of normal prion protein (PrP) to its pathogenic form, but concern remains that some reported sporadic CJD cases may actually be caused by disease transmission via iatrogenic processes. For cases with methionine homozygosity (CJD-MM) at codon 129 of the PRNP gene, recent research has pointed to plaque-like PrP deposition as a potential marker of iatrogenic transmission for a subset of cases. This phenotype is theorized to originate from specific iatrogenic source CJD types that comprise roughly a quarter of known CJD cases.

Methods

We reviewed scientific literature for studies which described PrP plaques among CJD patients with known epidemiological links to iatrogenic transmission (receipt of cadaveric human grown hormone or dura mater), as well as in cases of reported sporadic CJD. The presence and description of plaques, along with CJD classification type and other contextual factors, were used to summarize the current evidence regarding plaques as a potential marker of iatrogenic transmission. In addition, 523 cases of reported sporadic CJD cases in the US from January 2013 through September 2017 were assessed for presence of PrP plaques.

Results

We identified four studies describing 52 total cases of CJD-MM among either dura mater recipients or growth hormone recipients, of which 30 were identified as having PrP plaques. While sporadic cases were not generally described as having plaques, we did identify case reports which described plaques among sporadic MM2 cases as well as case reports of plaques exclusively in white matter among sporadic MM1 cases. Among the 523 reported sporadic CJD cases, 0 of 366 MM1 cases had plaques, 2 of 48 MM2 cases had kuru plaques, and 4 of 109 MM1+2 cases had either kuru plaques or both kuru and florid plaques. Medical chart review of the six reported sporadic CJD cases with plaques did not reveal clinical histories suggestive of potential iatrogenic transmission.

Conclusions

PrP plaques occur much more frequently for iatrogenic CJD-MM cases compared to sporadic CJDMM cases. Plaques may indicate iatrogenic transmission for CJD-MM cases without a type 2 Western blot fragment. The study results suggest the absence of significant misclassifications of iatrogenic CJD as sporadic. To our knowledge, this study is the first to describe grey matter kuru plaques in apparently sporadic CJD-MM patients with a type 2 Western blot fragment.

=====

P180 Clinico-pathological analysis of human prion diseases in a brain bank series

Ximelis T (1), Aldecoa I (1,2), Molina-Porcel L (1,3), Grau-Rivera O (4), Ferrer I (5), Nos C (6), Gelpi E (1,7), Sánchez-Valle R (1,4)

(1) Neurological Tissue Bank of the Biobanc-Hospital ClÃnic-IDIBAPS, Barcelona, Spain (2) Pathological Service of Hospital ClÃnic de Barcelona, Barcelona, Spain (3) EAIA Trastorns Cognitius, Centre Emili Mira, Parc de Salut Mar, Barcelona, Spain (4) Department of Neurology of Hospital ClÃnic de Barcelona, Barcelona, Spain (5) Institute of Neuropathology, Hospital Universitari de Bellvitge, Hospitalet de Llobregat, Barcelona (6) General subdirectorate of Surveillance and Response to Emergencies in Public Health, Department of Public Health in Catalonia, Barcelona, Spain (7) Institute of Neurology, Medical University of Vienna, Vienna, Austria.

Background and objective:

The Neurological Tissue Bank (NTB) of the Hospital Clínic-Institut d‘Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain is the reference center in Catalonia for the neuropathological study of prion diseases in the region since 2001. The aim of this study is to analyse the characteristics of the confirmed prion diseases registered at the NTB during the last 15 years.

Methods:

We reviewed retrospectively all neuropathologically confirmed cases registered during the period January 2001 to December 2016.

Results:

176 cases (54,3% female, mean age: 67,5 years and age range: 25-86 years) of neuropathological confirmed prion diseases have been studied at the NTB. 152 cases corresponded to sporadic Creutzfeldt-Jakob disease (sCJD), 10 to genetic CJD, 10 to Fatal Familial Insomnia, 2 to GerstmannSträussler-Scheinker disease, and 2 cases to variably protease-sensitive prionopathy (VPSPr). Within sCJD subtypes the MM1 subtype was the most frequent, followed by the VV2 histotype.

Clinical and neuropathological diagnoses agreed in 166 cases (94%). The clinical diagnosis was not accurate in 10 patients with definite prion disease: 1 had a clinical diagnosis of Fronto-temporal dementia (FTD), 1 Niemann-Pick‘s disease, 1 Lewy Body‘s Disease, 2 Alzheimer‘s disease, 1 Cortico-basal syndrome and 2 undetermined dementia. Among patients with VPSPr, 1 had a clinical diagnosis of Amyotrophic lateral sclerosis (ALS) and the other one with FTD.

Concomitant pathologies are frequent in older age groups, mainly AD neuropathological changes were observed in these subjects.

Discussion:

A wide spectrum of human prion diseases have been identified in the NTB being the relative frequencies and main characteristics like other published series. There is a high rate of agreement between clinical and neuropathological diagnoses with prion diseases. These findings show the importance that public health has given to prion diseases during the past 15 years. Continuous surveillance of human prion disease allows identification of new emerging phenotypes. Brain tissue samples from these donors are available to the scientific community. For more information please visit:


=====

P192 Prion amplification techniques for the rapid evaluation of surface decontamination procedures

Bruyere-Ostells L (1), Mayran C (1), Belondrade M (1), Boublik Y (2), Haïk S (3), Fournier-Wirth C (1), Nicot S (1), Bougard D (1)

(1) Pathogenesis and control of chronic infections, Etablissement Français du Sang, Inserm, Université de Montpellier, Montpellier, France. (2) Centre de Recherche en Biologie cellulaire de Montpellier, CNRS, Université de Montpellier, Montpellier, France. (3) Inserm U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Université Paris 06 UMR S 1127, Institut du Cerveau et de la Moelle épinière, ICM, Paris, France.

Aims:

Transmissible Spongiform Encephalopathies (TSE) or prion diseases are a group of incurable and always fatal neurodegenerative disorders including Creutzfeldt-Jakob diseases (CJD) in humans. These pathologies include sporadic (sCJD), genetic and acquired (variant CJD) forms. By the past, sCJD and vCJD were transmitted by different prion contaminated biological materials to patients resulting in more than 400 iatrogenic cases (iCJD). The atypical nature and the biochemical properties of the infectious agent, formed by abnormal prion protein or PrPTSE, make it particularly resistant to conventional decontamination procedures. In addition, PrPTSE is widely distributed throughout the organism before clinical onset in vCJD and can also be detected in some peripheral tissues in sporadic CJD. Risk of iatrogenic transmission of CJD by contaminated medical device remains thus a concern for healthcare facilities. Bioassay is the gold standard method to evaluate the efficacy of prion decontamination procedures but is time-consuming and expensive. Here, we propose to compare in vitro prion amplification techniques: Protein Misfolding Cyclic Amplification (PMCA) and Real-Time Quaking Induced Conversion (RT-QuIC) for the detection of residual prions on surface after decontamination.

Methods:

Stainless steel wires, by mimicking the surface of surgical instruments, were proposed as a carrier model of prions for inactivation studies. To determine the sensitivity of the two amplification techniques on wires (Surf-PMCA and Surf-QuIC), steel wires were therefore contaminated with serial dilutions of brain homogenates (BH) from a 263k infected hamster and from a patient with sCJD (MM1 subtype). We then compared the different standard decontamination procedures including partially and fully efficient treatments by detecting the residual seeding activity on 263K and sCJD contaminated wires. We completed our study by the evaluation of marketed reagents endorsed for prion decontamination.

Results:

The two amplification techniques can detect minute quantities of PrPTSE adsorbed onto a single wire. 8/8 wires contaminated with a 10-6 dilution of 263k BH and 1/6 with the 10-8 dilution are positive with Surf-PMCA. Similar performances were obtained with Surf-QuIC on 263K: 10/16 wires contaminated with 10-6 dilution and 1/8 wires contaminated with 10-8 dilution are positive. Regarding the human sCJD-MM1 prion, Surf-QuIC allows us to detect 16/16 wires contaminated with 10-6 dilutions and 14/16 with 10-7 . Results obtained after decontamination treatments are very similar between 263K and sCJD prions. Efficiency of marketed treatments to remove prions is lower than expected.

Conclusions:

Surf-PMCA and Surf-QuIC are very sensitive methods for the detection of prions on wires and could be applied to prion decontamination studies for rapid evaluation of new treatments. Sodium hypochlorite is the only product to efficiently remove seeding activity of both 263K and sCJD prions.

=====

WA2 Oral transmission of CWD into Cynomolgus macaques: signs of atypical disease, prion conversion and infectivity in macaques and bio-assayed transgenic mice

Schatzl HM (1, 2), Hannaoui S (1, 2), Cheng Y-C (1, 2), Gilch S (1, 2), Beekes M (3), SchulzSchaeffer W (4), Stahl-Hennig C (5) and Czub S (2, 6)

(1) University of Calgary, Calgary Prion Research Unit, Calgary, Canada (2) University of Calgary, Faculty of Veterinary Medicine, Calgary, Canada, (3) Robert Koch Institute, Berlin, Germany, (4) University of Homburg/Saar, Homburg, Germany, (5) German Primate Center, Goettingen, Germany, (6) Canadian Food Inspection Agency (CFIA), Lethbridge, Canada.

To date, BSE is the only example of interspecies transmission of an animal prion disease into humans. The potential zoonotic transmission of CWD is an alarming issue and was addressed by many groups using a variety of in vitro and in vivo experimental systems. Evidence from these studies indicated a substantial, if not absolute, species barrier, aligning with the absence of epidemiological evidence suggesting transmission into humans. Studies in non-human primates were not conclusive so far, with oral transmission into new-world monkeys and no transmission into old-world monkeys. Our consortium has challenged 18 Cynomolgus macaques with characterized CWD material, focusing on oral transmission with muscle tissue. Some macaques have orally received a total of 5 kg of muscle material over a period of 2 years. After 5-7 years of incubation time some animals showed clinical symptoms indicative of prion disease, and prion neuropathology and PrPSc deposition were found in spinal cord and brain of euthanized animals. PrPSc in immunoblot was weakly detected in some spinal cord materials and various tissues tested positive in RT-QuIC, including lymph node and spleen homogenates. To prove prion infectivity in the macaque tissues, we have intracerebrally inoculated 2 lines of transgenic mice, expressing either elk or human PrP. At least 3 TgElk mice, receiving tissues from 2 different macaques, showed clinical signs of a progressive prion disease and brains were positive in immunoblot and RT-QuIC. Tissues (brain, spinal cord and spleen) from these and preclinical mice are currently tested using various read-outs and by second passage in mice. Transgenic mice expressing human PrP were so far negative for clear clinical prion disease (some mice >300 days p.i.). In parallel, the same macaque materials are inoculated into bank voles. Taken together, there is strong evidence of transmissibility of CWD orally into macaques and from macaque tissues into transgenic mouse models, although with an incomplete attack rate. The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology. Our ongoing studies will show whether the transmission of CWD into macaques and passage in transgenic mice represents a form of non-adaptive prion amplification, and whether macaque-adapted prions have the potential to infect mice expressing human PrP. The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD.

See also poster P103

***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD.

=====

WA16 Monitoring Potential CWD Transmission to Humans

Belay ED

Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA.

The spread of chronic wasting disease (CWD) in animals has raised concerns about increasing human exposure to the CWD agent via hunting and venison consumption, potentially facilitating CWD transmission to humans. Several studies have explored this possibility, including limited epidemiologic studies, in vitro experiments, and laboratory studies using various types of animal models. Most human exposures to the CWD agent in the United States would be expected to occur in association with deer and elk hunting in CWD-endemic areas. The Centers for Disease Control and Prevention (CDC) collaborated with state health departments in Colorado, Wisconsin, and Wyoming to identify persons at risk of CWD exposure and to monitor their vital status over time. Databases were established of persons who hunted in Colorado and Wyoming and those who reported consumption of venison from deer that later tested positive in Wisconsin. Information from the databases is periodically cross-checked with mortality data to determine the vital status and causes of death for deceased persons. Long-term follow-up of these hunters is needed to assess their risk of development of a prion disease linked to CWD exposure.

=====

P166 Characterization of CJD strain profiles in venison consumers and non-consumers from Alberta and Saskatchewan

Stephanie Booth (1,2), Lise Lamoureux (1), Debra Sorensen (1), Jennifer L. Myskiw (1,2), Megan Klassen (1,2), Michael Coulthart (3), Valerie Sim (4)

(1) Zoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg (2) Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg (3) Canadian CJD Surveillance System, Public Health Agency of Canada, Ottawa (4) Division of Neurology, Department of Medicine Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton.

Chronic wasting disease (CWD) is spreading rapidly through wild cervid populations in the Canadian provinces of Alberta and Saskatchewan. While this has implications for tourism and hunting, there is also concern over possible zoonotic transmission to humans who eat venison from infected deer. Whilst there is no evidence of any human cases of CWD to date, the Canadian CJD Surveillance System (CJDSS) in Canada is staying vigilant. When variant CJD occurred following exposure to BSE, the unique biochemical fingerprint of the pathologic PrP enabled a causal link to be confirmed. However, we cannot be sure what phenotype human CWD prions would present with, or indeed, whether this would be distinct from that see in sporadic CJD. Therefore we are undertaking a systematic analysis of the molecular diversity of CJD cases of individuals who resided in Alberta and Saskatchewan at their time of death comparing venison consumers and non-consumers, using a variety of clinical, imaging, pathological and biochemical markers. Our initial objective is to develop novel biochemical methodologies that will extend the baseline glycoform and genetic polymorphism typing that is already completed by the CJDSS. Firstly, we are reviewing MRI, EEG and pathology information from over 40 cases of CJD to select clinically affected areas for further investigation. Biochemical analysis will include assessment of the levels of protease sensitive and resistant prion protein, glycoform typing using 2D gel electrophoresis, testing seeding capabilities and kinetics of aggregation by quaking-induced conversion, and determining prion oligomer size distributions with asymmetric flow field fractionation with in-line light scattering. Progress and preliminary data will be presented. Ultimately, we intend to further define the relationship between PrP structure and disease phenotype and establish a baseline for the identification of future atypical CJD cases that may arise as a result of exposure to CWD.

=====

Source Prion Conference 2018 Abstracts




Wide distribution of prion infectivity in the peripheral tissues of vCJD and sCJD patients

Jean‑Yves Douet1 · Alvina Huor1 · Hervé Cassard1 · Séverine Lugan1 · Naima Aron1 · Mark Arnold2 · Didier Vilette1 · Juan‑Maria Torres3 · James W. Ironside4 · Olivier Andreoletti1

Received: 17 December 2020 / Revised: 18 January 2021 / Accepted: 19 January 2021 © The Author(s) 2021

Abstract

Sporadic Creutzfeldt-Jakob disease (sCJD) is the commonest human prion disease, occurring most likely as the consequence of spontaneous formation of abnormal prion protein in the central nervous system (CNS). Variant Creutzfeldt–Jakob disease (vCJD) is an acquired prion disease that was first identified in 1996. In marked contrast to vCJD, previous investigations in sCJD revealed either inconsistent levels or an absence of PrPSc in peripheral tissues. These findings contributed to the consensus that risks of transmitting sCJD as a consequence of non-CNS invasive clinical procedures were low. In this study, we systematically measured prion infectivity levels in CNS and peripheral tissues collected from vCJD and sCJD patients. Unexpectedly, prion infectivity was detected in a wide variety of peripheral tissues in sCJD cases. Although the sCJD infectivity levels varied unpredictably in the tissues sampled and between patients, these findings could impact on our perception of the possible transmission risks associated with sCJD.

snip...

Recently, bioassays in transgenic mice that express the human PrP gene and display a high sensitivity to sCJD demonstrated the presence of prion infectivity in the plasma and bone marrow of several sCJD patients [17, 32]. These results raised questions about the overall distribution of prion infectivity and transmission risks associated with other peripheral tissues from sCJD patients.

In this study, we measured the prion infectivity levels in a panel of tissues collected from vCJD and sCJD MM1 cases. These bioassays demonstrated that, as expected, consistent titres of infectivity were present in lymphoid tissues from vCJD patients. However, for the non-lymphoid peripheral tissues studied, variable and lower titres of infectivity were detected in both sCJD and vCJD patients. These findings could impact on our perception of the possible transmission risks associated with sCJD involving non-CNS invasive procedures.

snip...

Results

vCJD transmission 

Four clinical vCJD cases (Met129 homozygous) and one asymptomatic vCJD case (Met129/Val129 heterozygous) were selected on the basis of their clinico-pathological features and PrPres Western Blot profile in the brain (Table 1).

A panel of frozen tissues that included CNS (frontal cortex), and 14 different peripheral tissues (such as primary and secondary lymphoid tissues, endocrine and exocrine glands, gonads, kidney, lung, liver, heart and skeletal muscles) from each of these 5 cases was constituted (Table 2). Each sample (10% tissue homogenates) was inoculated by the intracerebral route (IC) to bovine PrP expressing mice (tgBov n=6 per sample, 20 μL per mouse); a bioassay model identified in previous studies as a sensitive and robust approach for the detection and the quantification of vCJD infectivity [15, 17].

In all four vCJD affected patients, the inoculation of frontal cortex homogenate resulted in a 100% attack rate disease transmission (Table 2). Only 5 out of the 54 peripheral tis-sues samples failed to transmit disease in tgBov. Each of the 14 different categories of peripheral tissues caused, at variable extent, occurrence of clinical TSE in tgBov. Based on these transmission results (positive versus absence of transmission), the pattern of vCJD infectivity in peripheral tissues was relatively similar across the four vCJD patients (Table 2).

No TSE clinical signs or PrPres accumulation in the brain was observed in tgBov inoculated with frontal cortex from the asymptomatic vCJD case (> 650 days post inoculation). 8 out of the 13 inoculated categories of peripheral tissues transmitted a disease (lymphoid organs, lung, heart, pancreas and thyroid) in tgBov (Table 2), which indicated a more restricted distribution of the prion infectivity in the organs of this asymptomatic Met/Val129 patient than in the clinically affected Met/Met129 vCJD patients.

The PrPres Western blot profile and the vacuolar lesions profiles observed in mice inoculated with peripheral tissues from both clinical vCJD and asymptomatic patients were identical to those observed in tgBov mice inoculated with the brain of the vCJD affected patients (Fig. 1).No transmission was observed in tgBov mice that received frontal cortex and peripheral tissues homogenates from a non CJD control patient (Met129 homozygous) (Table 2, Fig. 1).

sCJD transmission

Five sCJD patients were selected on the basis of their clin-ico-pathological features, genotype at codon 129 of the PRNP gene (Met129 homozygous) and PrPres Western Blot type 1 profile in the brain (MM1 sCJD cases) (Table 1). This is the commonest subtype of sCJD. A panel of 15 peripheral tissues collected from these MM1 sCJD patients was constituted. This panel matched the one investigated in vCJD affected patients (Table 3).

Each sample (10% tissue homogenates) was inoculated by the intracerebral route (IC) to Met129 human PrP expressing mice (tgMet, n= 6 per sample, 20μL per mouse), a mouse model that we already used to detect and quantify prion infectivity in MM1 sCJD patients [32].

The inoculation of 10% frontal cortex homogenates from the sCJD MM1 patients in tgMet (IC route, 6 mice, 20μL per mouse) resulted in a clinical TSE with mean survival times comprised between 200 and 240 days (Table 3). The PrPres WB profile and the vacuolar lesion profile in the brain of the tgMet indicated that a same prion strain was present in the frontal cortex of these five sCJD patients (Fig. 2).

Unexpectedly, in the majority of the cases, the inoculation in tgMet of the peripheral tissues from the same MM1 sCJD patients resulted in positive transmission. TgMet inoculation revealed the presence of prion infectivity in all the differ-ent categories of peripheral tissues except liver and gonads (Table 3).

However, in contrast with vCJD, the bioassay results (positive versus absence of transmission) indicated that the prion infectivity distribution pattern in peripheral tis-sues strongly differed between the five affected MM1 sCJD patients. For instance, in sCJD case 2, positive transmissions were observed in tgMet inoculated with 10 out of the 13 tested peripheral tissues including lymphoid tissues, salivary glands, kidney, heart and pancreas. In contrast, in sCJD case 3, positive transmissions were only observed for 4 out of the same 13 tissues (lung, adrenal gland, bone marrow and skeletal muscle), with no disease transmission resulting from inoculation of lymphoid tissues, salivary gland, kidney, heart or pancreas (Table 3).

Interestingly, bioassay of the lymphoid tissues (spleen, cervical lymph node and tonsil) resulted in a disease transmission in only 3 out of the 5 sCJD cases (cases 2, 4 and 5). These results support the contention that in MM1 sCJD patients, the presence / absence of infectivity in the lymphoid organs is apparently not a determinant driver of the accumulation of infectivity in the other categories of peripheral tissues.

Despite the differences in bioassay transmission pat-terns, the PrPres Western blot profile and the vacuolar lesions profiles overserved in tgMet mice inoculated with MM1 sCJD peripheral tissues and frontal cortex brain homogenates were identical (Fig. 2), indicating that the same prion strain was present in the peripheral tissues and the CNS of the five MM1 sCJD patients.

No transmission or PrPres accumulation was observed in tgMet mice inoculated with peripheral tissues from the non CJD control patient (Table 3, Fig. 2).

Infectivity titres estimates

In order to estimate the infectivity levels in the vCJD and MM1 sCJD patients’ tissues, we applied the method described by Arnold et al. [4]. This approach uses both the probability of survival (attack rate at each dilution) and the individual mouse survival time at each dilution. The relationship between the titre of inoculum and the prob-ability of infection and the length of the survival times were derived from data corresponding to endpoint titration of a vCJD and a MM1 reference isolate in tgBov and tgMet mice, respectively [17, 32]. A normal distribution for the relationship between dose and survival time was assumed and the probability of infection versus dose was assumed to follow a logistic regression curve (supplementary Fig. 1).

Using this approach, the infectious titre in the frontal cortex of the four vCJD patients was estimated to range between 106.11 and 106.74 ID50 IC in tgBov per gram of tis-sue (Table 2).

The estimated infectivity levels in secondary lymphoid tissues (spleen and cervical lymph node) were 1 to 4 log10 lower than in the frontal cortex of the same patient. Infectivity levels in the other categories of peripheral tissues were 2.5 to 6 log10 lower than in the frontal cortex (Table 2, Fig. 3).Strikingly, in some of the vCJD affected patients, infectivity levels in heart (vCJD-3 and 4), kidney (vCJD-3 and 4), lung(vCJD-3), salivary gland (vCJD-3 and 4) or thyroid (vCJD-4) were only 1 to 2 log10 lower than in the spleen and/or cervical lymph node (Table 2, Fig. 3).

As already stated, the distribution of the prion in the peripheral tissue of the vCJD asymptomatic case was more restricted than in vCJD affected patients (Fig. 3). However, when positive, the peripheral tissues from the asymptomatic patient displayed similar infectivity levels to those observed in the vCJD patients at the clinical stage of the disease (Table 2, Fig. 3).

In the MM1 sCJD patients, the estimated infectivity lev-els in the frontal cortex varied between 105.8 and 107.8 ID50IC in tgMet/gram (Table 3). Infectivity levels in peripheral tissues that scored positive in bioassay were 2.8 to 8 log10 lower than in the frontal cortex of the same patient (Table 3, Fig. 3). In all five cases, no obvious relationship seemed to exist between the infectivity level in the CNS (frontal cortex) and either the distribution or the levels of sCJD infectivity in their peripheral tissues (Fig. 3).

In the sCJD cases 2, 4 and 5, the lymphoid tissues dis-played maximal level of infectivity that were 3–3.5 log10 lower than those observed in the frontal cortex (Table 2, Fig. 3). Strikingly, the infectivity levels associated with some peripheral tissues such as salivary gland (sCJD2), heart (sCJD2), kidney (sCJD 2) or bone marrow (sCJD 5) could be equivalent or even higher than those measured in the lymphoid organs of the same patient (Table 2, Fig. 3).

Discussion 

vCJD associated risks 

Following the emergence of vCJD in the UK in 1996, the presence of abnormal prion protein in the lymphoid tissues of affected patients was rapidly identified [31, 55]. This immediately raised major concerns about the risk of its iatrogenic transmission of the disease (via contaminated surgical instruments and blood transfusion) and led, in many countries, to the implementation of specific preventing against this risk.

Despite a relatively limited number of identified clinical cases (n = 231), the most recent epidemiological studies indicated that 1 out 2000 people in the UK could carry the vCJD agent (as judged by the presence of abnormal prion protein detected by immunohistochemistry in lymphoid follicles in the appendix) and that the exposure period to BSE agent in the UK could have largely exceeded the period initially considered to be at risk (i.e. the 1985–1996 period) [22, 23]. Over the 25 years since the emergence of vCJD only five instances that are a likely consequence of iatrogenic vCJD transmission have come to light, all in the UK and all associated with blood and blood-products [36, 37, 46, 47]. No cases of vCJD due to iatrogenic transmission by medical or surgical procedures have been identified, indicating that the preventive measures implemented to mitigate its transmission were effective [26, 39]. 

The overall picture of the distribution and levels of prion infectivity in the tissues of both vCJD affected and asymptomatic patients that we here report confirm the numerous hypotheses and the mosaic of experimental data that were used to design the infection control measures that were successful in limiting iatrogenic vCJD transmissions. These results also reinforce the fact that vCJD transmission risks have not disappeared since each asymptomatic vCJD infected individual in a human population will continue to represent a potential source of disease transmission.

Peripheral tissue infectivity in sCJD 

Seminal transmission experiments of peripheral tissues from sCJD cases in primate models failed to detect infectivity in a large selection of peripheral tissues, body fluids and excretions (except in one liver sample) [10]. Abnormal PrP immunodetection techniques (Western blot and immunohistochemistry) also failed to reveal the presence of prion in the peripheral tissues of sCJD patients [27, 28].These findings led to the generally accepted view that prion infectivity in the sCJD remains mostly confined to the CNS.

In 2003, improved Western Blot protocols for PrPres immunodetection revealed the presence of prion in the spleen (10 positive out of 28 cases) and/or the skeletal muscle (8 positive out of 32 cases) [24]. More recently, trans-mission studies of sCJD tissues in human PrP expressing transgenic mice (using plasma and bone marrow samples) and in vitro amplification of prions in a small number of sCJD peripheral tissues (skin, kidney, lung, adrenal gland) provided further evidence to the view that prions can accumulate in the peripheral tissues of sCJD affected patients [17, 32, 43, 52].

The results that we here report provide unequivocal and definitive evidence of the widespread distribution of the prion infectivity in the peripheral tissues in MM1 sCJD patients.

Other types of patients

Since our study was restricted to MM1 sCJD cases (the commonest sCJD subtype), additional investigations will be necessary to formally establish that consistent accumulation of prions in peripheral tissues also occurs in patients with other PRNP genotypes (Met/Val129 and Val/Val129) and/or affected with other sCJD prion strains [11]. The presence of abnormal PrP (in spleen and the skeletal muscle) and infectivity (in bone marrow) already identified in MV2 and VV2 sCJD patients indicates that this phenomenon is unlikely to be limited to MM1 sCJD cases [24, 32].

Variability in sCJD patients

The nature of peripheral tissues that accumulated infectivity in sCJD and vCJD cases were relatively similar. While the patterns of prion distribution and the infectivity levels observed in the peripheral tissues were relatively homogenous in the vCJD cases, particularly in lymphoid tissues, a high degree of variability was observed across the sCJD cases. Brain vacuolar lesion profiling and PrPres WB typing confirmed that the same prion strain was present in the brain and the peripheral tissues of all the sCJD affected patients. This rules out the hypothesis that prion strain(s) difference(s) (between individuals or in tissues from a same individual) could be responsible for the observed variability.

The comparison of prion distribution pattern in sCJD case 2 (20-months clinical phase duration) and sCJD cases 1, 3, 4 and 5 patients (1–4 months clinical phase duration) might suggest that, at first glance, a longer clinical phase duration is likely to be associated with a more widespread distribution of prions in the body tissues. However, even if our study rep-resents an unprecedented effort for characterizing CJD agent distribution patterns in the organs of affected patients, the number of sCJD cases that we investigated is too limited to draw definitive conclusions. The characterisation of a larger cohort of sCJD patients will be necessary to establish the relationship that might exist between the distribution and/or infectivity levels in peripheral tissues and sCJD patient age at clinical onset and the duration of the clinical phase of the illness.

Iatrogenic transmission of CJD

Several hundred cases of iatrogenic CJD transmission (iCJD) have been reported worldwide, the vast majority of which are likely to represent transmissions from sCJD patients [9]. The principal sources of these outbreaks were intramuscular injections with contaminated human pituitary-derived growth hormone (226 cases) and implantation of dura mater grafts (228 cases) derived from human cadavers with undiagnosed sCJD infections. A small number of cases were apparently also caused by neurosurgery using contaminated neurosurgical instruments and EEG electrodes (6 cases), transplantation of corneal grafts (2 cases) and intramuscular injections with human pituitary-derived gonadotrophic hormone (4 cases) [9].These cases dramatically illustrate the high resistance of CJD prions to standard medical decontamination procedures and their particular abilities to bind to steel surgical instruments [19, 53]. Survival times in the individuals who were exposed to sCJD agent(s) by the peripheral route could be extremely long and variable; for instance, in patients that received intramuscular injection of contaminated human pituitary-derived growth hormone, the onset of clinical signs and symptoms of iatrogenic CJD could be observed between 4 and 42 years after the treatment [9].

In a context where sCJD infectivity is apparently limited to the CNS, the medical and surgical procedures responsible for iatrogenic transmission of the disease remain relatively limited, the overall risks for sCJD iatrogenic transmission are now considered to be remote since most of these established routes of transmission be avoided (e.g. the use of human pituitary-derived hormones and human dura mater grafts) [9]. 

Our detection of low levels of sCJD infectivity in nonCNS tissues such as lung, heart, muscle or even salivary gland was unexpected. We next reviewed the medical histories for the sCJD patients that we studied (Table 1), which revealed surgical procedures (s-CJD-2 and 4) and/or invasive medical examinations (polypectomy under colonoscopy sCJD-5) only few years before the clinical disease in these patients. Some years ago, the presence of infectivity in the plasma and the detection of abnormal prion protein in the urine of sCJD patients raised concerns about the risks of sCJD transmission by blood transfusion and plasma/urinederived medical products [17, 38]. The detection, in our study, of infectivity in the bone marrow and the kidney of sCJD patients further reinforces these concerns. 

Prion titres as measured by intracerebral inoculation in PrP over-expressing transgenic mice models can provide us with estimates of the relative infectivity levels present in the CNS and peripheral tissues of affected patients. This approach conforms to the current gold standard for quantification of prions. However, in a context where the amount of infectivity that would be necessary to transmit disease to another human remains unknown, the infectivity titre estimates (as established following intracerebral inoculation in a reporter animal model) cannot be used to directly infer transmission risks to patients. Other factors, including the various different potential exposure routes (subcutaneous, intramuscular, etc.) and the decontamination/ sterilisation methodologies used on the surgical instruments /materials involved, will also influence the transmission risk analysis [1].

In many industrialized countries, reliable CJD passive surveillance programs have been established for decades. The apparently stable and low prevalence of sCJD cases in these countries bring some reassurance about the low numbers of iatrogenic CJD cases in this century [9], per-haps reflecting the variable and lower prion titres detected in the non-CNS tissues in this study.

Guidelines are in place to mitigate and control the risk of iatrogenic transmission of CJD in a healthcare setting [1, 56]. The procedures for cleaning and decontamination of surgical instruments and/or medical equipment now includes an assessment of their potential contamination by prions. However, prions are notoriously resistant to physico/chemical treatments and decontamination process that would be efficient on these agents remain generally inapplicable to some surgical and medical equipment [54], resulting in recommendations to destroy neurosurgical instruments that have been used on the brain of a patient with definite or probable CJD. Furthermore, the presence of dementia or an evolving neurodegenerative disorder in a patient undergoing medical or surgical procedures triggers the use of specific protocols designed to prevent the risk of potential transmission of CJD from the equipment used (surgical tools, endoscopes, etc.). The use of cells/tissues/organs and body fluids from these groups of patients for therapeutic purposes (blood donations, tissue grafts, etc.) is also restricted [1, 56].

When considering the risk of iatrogenic transmission of prion agents from CJD patients, one fundamental question is: How early before the occurrence of clinical signs and symptoms is prion infectivity likely to be present in peripheral solid tissues, blood and urine?

All the samples that we used to establish infectivity levels in tissues were collected post mortem in sCJD and vCJD patients at the terminal stage of the disease. There is clear evidence for the presence of infectivity in the blood and the peripheral tissues years before the clinical onset of vCJD in asymptomatic infected patients [3, 8, 16, 17]. However, it is uncertain that the infectivity levels and distribution in the post mortem peripheral tissues of sCJD and vCJD patients reflect the situation that could be observed at a preclinical or early clinical stage in the same patients. In the absence of tissue samples collected from asymptomatic sCJD patients we are totally lacking in data, therefore trying to elaborate further on this question would be totally speculative.

In several forms of genetic prion disease, for example those associated with the E200K PRNP mutation, the clinical disease manifestations, PrPres WB signature and tissue PrPres distributions are similar to that in sCJD [34, 48]. Despite the ethical issues it might raise, the longitudinal collection of blood samples and body fluids, for research purposes, in consenting patients belonging to families affected by these genetic forms of prion diseases (with confirmed mutations of the PRNP gene) may represent the only possibility to address this question.

In conclusion, the systematic surveillance of CJD and related epidemiological studies in many countries confirm the decline of cases of iatrogenic CJD due to recognised medical or surgical procedures, such as human dura mater graft surgery or treatment with human pituitary-derived growth hormone. However, they do not exclude the possibility that iatrogenic transmission could at least partly account for some sCJD cases observed in the population, particularly in localized geographic regions with evidence of CJD case clusters [50].

Many uncertainties remain on the early stages of the prion accumulation and infectivity in the peripheral tis-sues in patients infected with sCJD. However, the results of this study suggest that the iatrogenic transmission risks associated with sCJD peripheral tissues should not be disregarded.



Improved surveillance of surgical instruments reprocessing following the variant Creutzfeldt-Jakob disease crisis in England: findings from a 3-year survey

J Hosp Infect . 2021 Jan 19;S0195-6701(21)00022-0. doi: 10.1016/j.jhin.2021.01.005. Online ahead of print. 

Improved surveillance of surgical instruments reprocessing following the variant Creutzfeldt-Jakob disease crisis in England: findings from a 3-year survey 

R C Hervé 1, Jean Hedges 2, C W Keevil 3 Affiliations expand PMID: 33482297 DOI: 10.1016/j.jhin.2021.01.005 Abstract Background: Sensitive, direct protein detection methods are now recommended for the inspection of reprocessed reusable surgical instruments in England to reduce the risk of prion transmission.

Aim: To implement an established, highly sensitive method to quantify proteinaceous residues on reprocessed instruments in a Sterile Services Department and evaluate its potential impact on service provision.

Methods: We introduced highly sensitive epifluorescence (EDIC/EF) microscopy in a large SSD. Over three years, we periodically tested two models of washer disinfector using stainless steel tokens spiked with mouse brain homogenate or Browne test soil for comparison. We also obtained data and feedback from staff who have been using EDIC/EF to examine nearly 3,000 reprocessed instruments.

Findings: All reprocessed test surfaces harboured residual contamination (up to 258.4 ng from 1 microgram spikes). Proximity between surfaces affected decontamination efficacy and allowed cross contamination. Up to 50 ng de novo proteinaceous contamination was deposited on control surfaces after a single AWD cycle. The test soil behaved differently than real tissue contamination. SSD staff observed proteinaceous residues on most reprocessed instruments using EDIC/EF, which can detect far smaller amounts than the currently accepted national threshold of five micrograms per side.

Conclusion: Implementing recent national guidelines to address the prions concern proved an eye-opener. Microscopic levels of proteins remain on many reprocessed instruments. The impact most of these residues, potentially including prions, may have on subsequent patients after sterilization remains debatable. Improving surveillance capability in SSDs can support decision making and raise the standards of surgical instruments reprocessing.

Keywords: Surgical instruments; prions; proteins; sterile service departments; surveillance.

Copyright © 2021. Published by Elsevier Ltd.


***>''Implementing recent national guidelines to address the prions concern proved an eye-opener. Microscopic levels of proteins remain on many reprocessed instruments. The impact most of these residues, potentially including prions, may have on subsequent patients after sterilization remains debatable.''<***

DEAD people can't debate this, and it's a damn shame that after 5 decades, or more, of discussing this, we now know what to do, but still refuse to do it i.e. disposable instruments,  jiminy cricket what the hell does it take, how many body bags of iatrogenic cjd (now called sporadic cjd in most cases still) does it take, i guess it's just too easy to call it sporadic cjd and go on down the road.

all iatrogenic cjd is, is sporadic cjd, before the iatrogenic event is discovered, traced back, provern, documented, put into the academic domain, and then finally the public domain, this very seldom happens, thus problem solved, it's all sporadic cjd, PLUS, SPORADIC CJD HAS NOW BEEN LINKED TO ATYPICAL AND TYPICAL BSE, SCRAPIE, AND NOW CWD. ...terry

Friday, January 29, 2021 
Scientists identify locations of early prion protein deposition in retina, what if?
Variant Creutzfeldt–Jakob Disease Diagnosed 7.5 Years after Occupational Exposure

Variant Creutzfeldt–Jakob disease was identified in a technician who had cut her thumb while handling brain sections of mice infected with adapted BSE 7.5 years earlier. The long incubation period was similar to that of the transfusion-transmitted form of the disease.

TO THE EDITOR:

We report a case of variant Creutzfeldt–Jakob disease (CJD) that was plausibly related to accidental occupational exposure in a technician who had handled murine samples contaminated with the agent that causes bovine spongiform encephalopathy (BSE) 7.5 years earlier.

In May 2010, when the patient was 24 years of age, she worked in a prion research laboratory, where she handled frozen sections of brain of transgenic mice that overexpressed the human prion protein with methionine at codon 129. The mice had been infected with a sheep-adapted form of BSE. During this process, she stabbed her thumb through a double pair of latex gloves with the sharp ends of a curved forceps used to handle the samples. Bleeding was noted at the puncture site.

In November 2017, she began having burning pain in the right shoulder and neck. The pain worsened and spread to the right half of her body during the following 6 months. In November 2018, an examination of a sample of cerebrospinal fluid (CSF) obtained from the patient was normal. Magnetic resonance imaging (MRI) of the brain showed a slight increase in the fluid-attenuated inversion recovery (FLAIR) signal in the caudates and thalami (Fig. S1A and S1B in the Supplementary Appendix, available with the full text of this letter at NEJM.org). In January 2019, she became depressed and anxious and had memory impairment and visual hallucinations. There was hypertonia on the right side of her body. At that time, an analysis of CSF for 14-3-3 protein was negative. In March 2019, MRI showed an increased FLAIR signal in pulvinar and dorsomedial nuclei of thalami (Fig. S1C through S1E).

The patient was found to be homozygous for methionine at codon 129 of the prion protein gene without mutation. An analysis of a sample of CSF on real-time quaking-induced conversion analysis was negative for a diagnosis of sporadic CJD. However, an analysis of plasma and CSF by means of protein misfolding cyclic amplification was positive for the diagnosis of variant CJD (Figure 1A and 1B). The patient died 19 months after the onset of symptoms. Neuropathological examination confirmed the diagnosis of variant CJD (Figure 1C and 1D). Western blot analysis showed the presence of type 2B protease-resistant prion protein in all sampled brain areas. The clinical characteristics of the patient and the postmortem neuropathological features were similar to those observed in 27 patients with variant CJD who had previously been reported in France.1 (Additional details are provided in the Supplementary Appendix.)

There are two potential explanations for this patient’s condition. Oral transmission from contaminated cattle products cannot be ruled out because the patient was born at the beginning of the French BSE outbreak in cattle. However, the last two patients who had confirmed variant CJD with methionine homozygosity at codon 129 in France and the United Kingdom died in 2014 and 2013, respectively, which makes oral transmission unlikely. In France, the risk of variant CJD in 2019 was negligible or nonexistent in the post-1969 birth cohort.2

Percutaneous exposure to prion-contaminated material is plausible in this patient, since the prion strain that she had handled was consistent with the development of variant CJD.3 The 7.5-year delay between the laboratory accident and her clinical symptoms is congruent with the incubation period in the transfusion-transmitted form of the disease. The ability of this strain to propagate through the peripheral route has been documented, and experimental studies with scrapie strains have shown that scarification and subcutaneous inoculation are effective routes.4,5 The last known Italian patient with variant CJD, who died in 2016, had had occupational contact with BSE-infected brain tissues, although subsequent investigation did not disclose a laboratory accident (Pocchiari M, Italian Registry of CJD: personal communication). Thus, the last two cases of variant CJD outside the United Kingdom have been associated with potential occupational exposure. Such cases highlight the need for improvements in the prevention of transmission of variant CJD and other prions that can affect humans in the laboratory and neurosurgery settings, as outlined in the Supplementary Appendix.

Jean-Philippe Brandel, M.D. Assistance Publique–Hôpitaux de Paris, Paris, France

M. Bustuchina Vlaicu, M.D. Groupe Hospitalier Nord-Essonne, Orsay, France

Audrey Culeux, B.Sc. INSERM Unité 1127, Paris, France

Maxime Belondrade, M.Sc. Daisy Bougard, Ph.D. Etablissement Français du Sang, Montpellier, France

Katarina Grznarova, Ph.D. Angeline Denouel, M.Sc. INSERM Unité 1127, Paris, France

Isabelle Plu, M.D. Elodie Bouaziz-Amar, Pharm.D., Ph.D. Danielle Seilhean, M.D., Ph.D. Assistance Publique–Hôpitaux de Paris, Paris, France

Michèle Levasseur, M.D. Groupe Hospitalier Nord-Essonne, Orsay, France

Stéphane Haïk, M.D., Ph.D. INSERM Unité 1127, Paris, France stephane.haik@upmc.fr

Supported by a grant (ANR-10-IAIHU-06) from Programme d’Investissements d’Avenir and Santé Publique France.

Disclosure forms provided by the authors are available with the full text of this letter at NEJM.org.

July 2, 2020 N Engl J Med 2020; 383:83-85 DOI: 10.1056/NEJMc2000687


Supplementary Appendix

This appendix has been provided by the authors to give readers additional information about their work. Supplement to: Brandel J-P, Vlaicu MB, Culeux A, et al. Variant Creutzfeldt–Jakob disease diagnosed 7.5 years after occupational exposure. N Engl J Med 2020;383:83-5. DOI: 10.1056/NEJMc2000687

Full case report

A woman, born in 1986, with only a medical history of dental avulsion and the removal of a nevus started to complain, in November 2017, of burning pain in the right shoulder and the right side of the neck. Over the next 6 months, the pain worsened and spread to the right half-body including the buttocks, the back of the thigh and the foot sole, and the face with ear pain. After several consultations, a first hospital assessment was carried out in November 2018. CSF examination was normal and brain MRI interpreted as normal despite slight high signals in the caudate nucleus and thalami (Supplementary figure 1). The diagnosis of Lyme disease was suspected and treatment with ceftriaxone was initiated. Pain persisted and the patient who was showing signs of depression was referred to a psychiatrist for antidepressant treatment. Memory impairment was noted by relatives in January 2019 and the patient was admitted to a neurology department in February 2019. Right extrapyramidal hypertonia, visual hallucinations and memory problems of recent events were observed. Neurological alterations were associated with severe anxiety. Inflammatory markers, biological and immunological assessments were normal. Serology for conventional agents was negative. Detection of anti-neuronal, anti-thyroid peroxidase, anti-thyroglobulin and anti-thyroidstimulating hormone receptor antibodies yielded negative results. Vitamin B1 and B6 levels were within normal limits. Standard CSF analysis was normal and 14-3-3 protein detection was negative. MRI from mid-March 2019 showed a high signal on the FLAIR sequences in the pulvinar and dorsomedian nuclei of the thalamus, bilaterally, more intense than those observed in the striatum (Supplementary figure 1). A generally slow activity was observed on EEGs. PRNP analysis revealed a homozygous methionine-methionine (MM) genotype at codon 129 without mutation. At this time, the patient fulfilled criteria of probable vCJD. Two different protein misfolding amplification methods were performed. As predicted in a suspected case of vCJD, RT-QuIC detection in the CSF gave a negative result.1 A PMCA test, recently validated for the diagnosis of vCJD in plasma and CSF was performed.2,3 PMCA detection was positive in plasma and CSF. Evolution was marked by the worsening of cognitive impairment, a small step with balance disorders and an extrapyramidal syndrome.

The patient died 19 months after disease onset.

Neuropathological examination confirmed the diagnosis of vCJD by showing typical florid plaques in the cerebral cortex and cerebellum. Spongiform changes, gliosis and neuronal loss were predominantly observed in the subcortical gray matter. In addition, PrP immunohistochemistry showed multicentric plaques, clumpses, peri-cellular and peri-vascular PrP deposition (Supplementary figure 2). Western blot detection of PrPres was positive and type 2B PrPres was consistently detected in all studied brain areas.

The epidemiological survey revealed that the patient had been employed from 2009 to 2012 in a laboratory involved in prion research. In particular, she has worked on transgenic animal models expressing human and bovine PrP and infected with strains of human or bovine prions. The patient had two work accidents. In May 2010, she stabbed her thumb with sharp ends curved forceps used to handle brain frozen sections of humanized transgenic mice infected with a sheep-adapted BSE agent. The mouse brain handled at the time of the accident was from a secondary intra-cerebral subpassage of sheep BSE in transgenic mice overexpressing a methionine 129-human PrP. To note transmission studies indicate a low or absent transmission barrier to sheep BSE in human M129-PrP mice. The neuropathological phenotype is similar to that observed in mice infected with cattle BSE or vCJD suggesting that sheep-BSE could act as a causal vCJD agent especially in codon 129-methionine homozygotes.

4,5 The patient immediately noticed a bleeding wound. After leaving the level 3 biosafety laboratory, the wounded finger was cleaned with water and immersed for more than ten minutes in a freshly diluted 2% sodium hypochlorite solution. The second accident occurred in September 2011 in a conventional laboratory with no contact with infectious prion material. No other risk factors were identified with the exception, as most French people in her age cohort, a dietary exposure from 1986 to 1996 to bovine products with a BSE risk. 

4

Methods

Clinical and epidemiological data As with all other cases of French vCJD, a direct interview with the patient’s family was conducted. Clinical data were extracted from the medical records and further information was collected using the European network (EuroCJD) questionnaire. The data collected were gender, age at onset and death, clinical features, results of investigations, and specific medical risk factors. These included history of growth hormone therapy, transplantation, surgery, blood transfusion, blood products therapy (albumin, immunoglobulin, clotting factors), vaccinations, professional activity, and stays in UK. The reports of the two accidents at work were collected. Additional data were obtained from the authorities of the research institute. They explained precisely how the patient had been injured, the biological materials handled and how the wounds had been disinfected and treated. Genetic analysis The prion protein gene (PRNP) was analyzed as described previously to obtain the genotype at codon 129 and to exclude a pathogenic mutation.6 An informed consent for genetic analysis was obtained from the patient's husband.

Neuropathological analysis

Samples were taken from 1cm-thick coronal sections after two months of fixation in 10% formalin as described previously.7 After formic acid treatment, specimens were embedded in paraffin. Threemicrometer-thick sections were stained with hematoxylin and eosin and Periodic Acid–Schiff (PAS) methods. PrP immunohistochemistry was performed using the 12F10 mouse monoclonal antibody.8,9 Biochemical analysis PrPres analysis by Western blot was performed from frozen samples of the brain. Tissue homogenization, digestion with proteinase K, purification, electrophoresis and immunoblotting were 

5

done as described previously.10 The biochemical classification according to Parchi and colleagues was used.11

Amplification methods

RT-QuIC analysis in the CSF was performed using hamster full-length (23–231) recombinant PrP as previously described.12 Thirty µl of CSF per well were added and analysis was performed in quadruplicate using a BMG-LABTECH Omega. PMCA amplification in plasma and CSF was performed as described by using brains from transgenic mice overexpressing human M129-PrP as substrate.2,3 For plasma samples, a capture of abnormal PrP using plasminogen-coated magnetic nanobeads was performed before serial amplification. Each round of PMCA comprised 80 cycles of 30 min incubation/20 s sonication. Implications If one considers our patient as a case of a documented accidental transmission of CJD in a research laboratory, several important points should be stressed:

- A single puncture without hollow needle containing infectious material is sufficient to transmit prions in human even with a short contact.

- The incubation period is similar to that seen in MM patients with transfusion-transmitted vCJD, suggesting that the level of accidentally delivered infectious dose is in the same range as that contained in a unit of non-leukodepleted red blood cells.

- Immersing this type of lesion in a freshly diluted 2% sodium hypochlorite solution was not sufficient to prevent contamination. Important consequences in terms of prevention of occupational risks and public health issue associated with prions should be underlined:

6

- Individual protection against accidental wounds should be reinforced in research laboratories, neuropathology department and autopsy rooms. Neurosurgery teams should take the risk into account, especially when a cortical biopsy is performed to explore patients with unexplained encephalopathy. This implies accurate information and training of exposed professionals.

- The efficacy of decontamination procedures to be applied in case of accidental exposure has not been demonstrated using adequate in vivo models of transmission. A more aggressive postexposure management is to be defined and validated experimentally.

- The mechanisms of prion neuro-invasion in this specific scenario are unknown and may involve prion propagation through (1) the peripheral innervation of digital pulp, (2) an up-take by phagocytes driving prion replication in the lymphoid system followed by propagation via the autonomous nervous system or (3) blood transport.

- No preventive treatment is available to date. While a few approaches that may limit peripheral prion propagation and neuro-invasion have been proposed (such as corticoids and pentosan polysulfate), their efficiency in such a transmission pattern and in the use of relevant prion strains has to be confirmed.

7

References

1. Zanusso G, Monaco S, Pocchiari M, Caughey B. Advanced tests for early and accurate diagnosis of Creutzfeldt-Jakob disease. Nat Rev Neurol 2016;12:325-33.

2. Bougard D, Brandel JP, Belondrade M, et al. Detection of prions in the plasma of presymptomatic and symptomatic patients with variant Creutzfeldt-Jakob disease. Science translational medicine 2016;8:370ra182.

3. Bougard D, Belondrade M, Mayran C, et al. Diagnosis of Methionine/Valine Variant Creutzfeldt-Jakob Disease by Protein Misfolding Cyclic Amplification. Emerging infectious diseases 2018;24:1364-6.

4. Plinston C, Hart P, Chong A, et al. Increased susceptibility of human-PrP transgenic mice to bovine spongiform encephalopathy infection following passage in sheep. Journal of virology 2011;85:1174-81.

5. Joiner S, Asante EA, Linehan JM, et al. Experimental sheep BSE prions generate the vCJD phenotype when serially passaged in transgenic mice expressing human prion protein. J Neurol Sci 2018;386:4-11.

6. Laplanche JL, Delasnerie-Lauprêtre N, Brandel JP, et al. Molecular genetics of prion diseases in France. Neurology 1994;44:2347-51.

7. Hauw JJ, Sazdovitch V, Laplanche JL, et al. Neuropathologic variants of sporadic CreutzfeldtJakob disease and codon 129 of PrP gene. Neurology 2000;54:1641-6.

8. Haik S, Faucheux BA, Sazdovitch V, et al. The sympathetic nervous system is involved in variant Creutzfeldt-Jakob disease. Nature medicine 2003;9:1121-3.

9. Privat N, Laffont-Proust I, Faucheux BA, et al. Human prion diseases: from antibody screening to a standardized fast immunodiagnosis using automation. Mod Pathol 2008;21:140-9.

8

10. Levavasseur E, Laffont-Proust I, Morain E, et al. Regulating factors of PrP glycosylation in Creutzfeldt-Jakob disease--implications for the dissemination and the diagnosis of human prion strains. PloS one 2008;3:e2786.

11. Parchi P, Notari S, Weber P, et al. Inter-laboratory assessment of PrPSc typing in creutzfeldtjakob disease: a Western blot study within the NeuroPrion Consortium. Brain pathology 2009;19:384- 91.

12. McGuire LI, Poleggi A, Poggiolini I, et al. Cerebrospinal fluid real-time quaking-induced conversion is a robust and reliable test for sporadic creutzfeldt-jakob disease: An international study. Annals of neurology 2016;80:160-5.

snip...


Variant Creutzfeldt–Jakob Disease Diagnosed 7.5 Years after Occupational Exposure

Variant Creutzfeldt–Jakob disease was identified in a technician who had cut her thumb while handling brain sections of mice infected with adapted BSE 7.5 years earlier. The long incubation period was similar to that of the transfusion-transmitted form of the disease.


Friday, January 29, 2021 
Scientists identify locations of early prion protein deposition in retina, what if?

Saturday, January 23, 2021 

Improved surveillance of surgical instruments reprocessing following the variant Creutzfeldt-Jakob disease crisis in England: findings from a 3-year survey https://itseprion.blogspot.com/2021/01/improved-surveillance-of-surgical.html



FRIDAY, JANUARY 31, 2020 

CJD TSE Prion Blood Products, iatrogenic transmission, Confucius is confused again, WHAT IF? Docket Number: FDA-2012-D-0307


Volume 26, Number 8—August 2020 

Sporadic Creutzfeldt-Jakob Disease among Physicians, Germany, 1993–2018 high proportion of physicians with sCJD were surgeons


SUNDAY, JULY 19, 2020 

Joseph J. Zubak Orthopaedic surgeon passed away Monday, July 6, 2020, Creutzfeldt-Jakob Disease (CJD)


FRIDAY, SEPTEMBER 06, 2019 

Disinfection of Multi-Use Ocular Equipment for Ophthalmological Procedures: A Review of Clinical Effectiveness, Cost-Effectiveness, and Guidelines


all iatrogenic cjd is, is sporadic cjd, before the iatrogenic event is discovered, traced back, provern, documented, put into the academic domain, and then finally the public domain, this very seldom happens, thus problem solved, it's all sporadic cjd, PLUS, SPORADIC CJD HAS NOW BEEN LINKED TO ATYPICAL AND TYPICAL BSE, SCRAPIE, AND NOW CWD. ...terry

vpspr, sgss, sffi, TSE, an iatrogenic by-product of gss, ffi, familial type prion disease, what if ???

Greetings Friends, Neighbors, and Colleagues,



Wednesday, September 11, 2019 

Is the re-use of sterilized implant abutments safe enough? (Implant abutment safety) iatrogenic TSE Prion


FRIDAY, APRIL 21, 2017 

URGENT GLOBAL UPDATE BLOOD, TISSUE, CJD, nvCJD, GSS, BSE, CWD, SCRAPIE, TSE, PRION 


SUNDAY, OCTOBER 27, 2013 

A Kiss of a Prion: New Implications for Oral Transmissibility


THURSDAY, MAY 17, 2012 

Iatrogenic Creutzfeldt-Jakob Disease, Final Assessment Volume 18, Number 6—June 2012


boy did they miss this next one;

THURSDAY, MAY 17, 2012 

Iatrogenic Creutzfeldt-Jakob Disease, Final Assessment Volume 18, Number 6—June 2012


Thursday, April 12, 2012
 
Health professions and risk of sporadic Creutzfeldt–Jakob disease, 1965 to 2010
 
Eurosurveillance, Volume 17, Issue 15, 12 April 2012
 
Research articles
 

i tried to tell GUT journal, and Bramble et al this way back, decades ago...terry

were not all CJDs, even nvCJD, just sporadic, until proven otherwise?

Terry S. Singeltary Sr., P.O. BOX, Bacliff, Texas 77518 USA


Professor Michael Farthing wrote:

Louise Send this to Bramble (author) for a comment before we post. Michael 

-----Original Message----- 

From: Terry S. Singeltary Sr. [mailto:flounder@wt.net] ;

Sent: 03 June 2002 17:14 


Subject: gutjnl_el;21 Terry S. Singeltary Sr. (3 Jun 2002) "CJDs (all human TSEs) and Endoscopy Equipment" 

----------------------------------------------------------------- 

Date submitted: 3 Jun 2002 eLetter ID: gutjnl_el;21

Gut eLetter for Bramble and Ironside 50 (6): 888 

----------------------------------------------------------------- 

Name: Terry S. Singeltary Sr. Email: flounder@wt.net Title/position: disabled {neck injury} Place of work: CJD WATCH IP address: 216.119.162.85 Hostname: 216-119-162-85.ipset44.wt.net Browser: Mozilla/5.0 (Windows; U; Win98; en-US; rv:0.9.4) Gecko/20011019 Netscape6/6.2

Parent ID: 50/6/888 

Citation: Creutzfeldt-Jakob disease: implications for gastroenterology 

M G Bramble and J W Ironside Gut 2002; 50: 888-890 (Occasional viewpoint) 



----------------------------------------------------------------- 

"CJDs (all human TSEs) and Endoscopy Equipment" 

-----------------------------------------------------------------

regarding your article;

Creutzfeldt-Jakob disease: implications for gastroenterology

i belong to several support groups for victims and relatives of CJDs. several years ago i did a survey regarding endoscopy equipment and how many victims of CJDs have had any type of this procedure done. to my surprise, many victims had some kind of endoscopy work done on them. as this may not be a smoking gun, i think it should warrant a 'red flag' of sorts, especially since data now suggests a substantial TSE infectivity in the gut wall of species infected with TSEs. If such transmissions occur, the ramifications of spreading TSEs from endoscopy equipment to the general public would be horrible, and could potential amplify the transmission of TSEs through other surgical procedures in that persons life, due to long incubation and sub-clinical infection. Science to date, has well established transmission of sporadic CJDs with medical/surgical procedures.

Terry S. Singeltary Sr. CJD WATCH

Subject: Re: gutjnl_el;21 Terry S. Singeltary Sr. (3 Jun 2002) "CJDs (all human TSEs) and Endoscopy Equipment" Date: Thu, 20 Jun 2002 16:19:51 -0700 From: "Terry S. Singeltary Sr." To: Professor Michael Farthing CC: lcamp@BMJgroup.com References: <001501c21099$5c8bc620$7c58d182@mfacdean1.cent.gla.ac.uk>

Greetings again Professor Farthing and BMJ,

I was curious why my small rebuttal of the article described below was not listed in this month's journal of GUT? I had thought it was going to be published, but I do not have full text access. Will it be published in the future? Regardless, I thought would pass on a more lengthy rebuttal of mine on this topic, vCJD vs sCJDs and endoscopy equipment. I don't expect it to be published, but thought you might find it interesting, i hope you don't mind and hope to hear back from someone on the questions I posed...

Here is my short submission I speak of, lengthy one to follow below that:

Date submitted: 3 Jun 2002

snip...see full text;

Friday, September 27, 2019

Prion disease and recommended procedures for flexible endoscope reprocessing – a review of policies worldwide and proposal for a simplified approach Singeltary, GUT journal and Bramble et al 

 
Saturday, January 16, 2010
 
*** Evidence For CJD TSE Transmission Via Endoscopes 1-24-3 re-Singeltary to Bramble et al
 
Evidence For CJD/TSE Transmission Via Endoscopes
 
From Terry S. Singletary, Sr flounder@wt.net 1-24-3
 
Terry S. Singeltary Sr., P.O. , Bacliff, Texas 77518 USA
 
 
Professor Michael Farthing wrote:
 
*** Louise Send this to Bramble (author) for a comment before we post. Michael
 


 re-Human Prion Diseases in the United States Posted by flounder on 01 Jan 2010 at 18:11 GMT    


Research articles Health professions and risk of sporadic Creutzfeldt– Jakob disease, 1965 to 2010

15. Terry S. Singeltary Sr. Doctor Antonio Ruiz Villaespesa, pathologist and CJD researcher deceased because of Creutzfeldt-Jakob Disease SPAIN. 21 Apr 2009. [Accessed 11 Apr 2012]. In: Monitoring the occurrence of emerging forms of CJD [blog]. Available from: 



Monday, August 17, 2009

Transmissible Spongiform Encephalopathy Agents: Safe Working and the Prevention of Infection: Annex J,K, AND D Published: 2009


Thursday, February 26, 2009 

SEAC 102nd Meeting on Wednesday 4 March 2009 (SEE DH risk assessment on sourcing and pooling plasma) 


TUESDAY, AUGUST 12, 2008 

Biosafety in Microbiological and Biomedical Laboratories Fifth Edition 2007 (occupational exposure to prion diseases)

 
Wednesday, August 20, 2008
 
Tonometer disinfection practice in the United Kingdom: A national survey
 
 
Tuesday, August 12, 2008
 
Biosafety in Microbiological and Biomedical Laboratories Fifth Edition 2007 (occupational exposure to prion diseases)
 
 
Monday, December 31, 2007
 
Risk Assessment of Transmission of Sporadic Creutzfeldt-Jakob Disease in Endodontic Practice in Absence of Adequate Prion Inactivation
 
 
Subject: CJD: update for dental staff
 
Date: November 12, 2006 at 3:25 pm PST
 
1: Dent Update. 2006 Oct;33(8):454-6, 458-60.
 
CJD: update for dental staff.
 


40,000 human heart valves a year from BSE herds

Sun, 3 Sep 2000. 

Unpublished Inquiry documents obtained by CJD activist Terry S. Singeltary Sr. of Bacliff, Texas


FRIDAY, JANUARY 31, 2020 

CJD TSE Prion Blood Products, iatrogenic transmission, Confucius is confused again, WHAT IF? Docket Number: FDA-2012-D-0307


CJD TSE Prion Blood Products, iatrogenic transmission, Confucius is confused again, WHAT IF?

''In the 2016 guidance, we recommended that prospective blood donors should be indefinitely deferred if they report having a blood relative with CJD. However, almost all cases reported are sCJD, not a genetic form of CJD. Blood relatives of individuals with sCJD are not at increased risk of developing the disease. The rare genetic forms of CJD (e.g., fCJD, GSS, FFI) share pathophysiological features with sCJD, and the transmission risk by blood components remains theoretical. Consequently, we recommend that establishments may stop asking prospective donors about having blood relatives with CJD.''


Confucius is confused again?

''The rare genetic forms of CJD (e.g., fCJD, GSS, FFI) share pathophysiological features with sCJD, and the transmission risk by blood components remains theoretical. Consequently, we recommend that establishments may stop asking prospective donors about having blood relatives with CJD.''

YET, vpspr, sporadic FFI, sporadic GSS, or the pending cases that can't be identified, are all now listed as sporadic CJD.

WHAT IF, sGSS, sFFI, are of an iatrogenic event from iatrogenic donor being from GSS or FFI?

what if vpspr is another strain of a different sporadic CJD, or familial? see;

7Includes 21 (21 from 2019) cases with type determination pending in which the diagnosis of vCJD has been excluded. 

8The sporadic cases include 3831 cases of sporadic Creutzfeldt-Jakob disease (sCJD), 67 cases of Variably Protease-Sensitive Prionopathy (VPSPr) and 35 cases of sporadic Fatal Insomnia (sFI). 

9Total does not include 264 Familial cases diagnosed by blood test only.


under new proposed guidelines ''we recommend that establishments may stop asking prospective donors about having blood relatives with CJD'' (of which i strongly oppose due to the fact sporadic cjd is not a single entity or a spontaneous event, never which have been proven), but under these guidelines, you will miss the vpspr, sgss, and sffi, because they are under sporadic cjd terminology, would you not?

The occurrence of the disease in a patient who had contact with cases of familial C.J.D., but was not genetically related, has been described in Chile (Galvez et al., 1980) and in France (Brown et al., 1979b). In Chile the patient was related by marriage, but with no consanguinity, and had social contact with subsequently affected family members for 13 years before developing the disease. The contact case in France also married into a family in which C.J.D. was prevalent and had close contact with an affected member. In neither instance did the spouse of the non-familial case have the disease. The case described in this report was similarly related to affected family members and social contact had occurred for 20 years prior to developing C.J.D. If contact transmission had occurred, the minimum transmission period would be 11 years. Contact between sporadic cases has not been described and it is remarkable that possible contact transmissions have all been with familial cases. No method of transmission by casual social contact has been suggested.

WHAT IF?

***The occurrence of contact cases raises the possibility that transmission in families may be effected by an unusually virulent strain of the agent.

snip...see full text here;



Sporadic Creutzfeldt-Jakob Disease in a Woman Married Into a Gerstmann-Sträussler-Scheinker Family: An Investigation of Prions Transmission via Microchimerism 

Aušrinė Areškevičiūtė, MSc, Linea Cecilie Melchior, PhD, Helle Broholm, MD, Lars-Henrik Krarup, MD, PhD, Suzanne Granhøj Lindquist, MD, PhD, Peter Johansen, PhD, Neil McKenzie, PhD, Alison Green, PhD, Jørgen Erik Nielsen, MD, PhD, Henning Laursen, Dr.Med, Eva Løbner Lund, MD, PhD Journal of Neuropathology & Experimental Neurology, Volume 77, Issue 8, August 2018, Pages 673–684, https://doi.org/10.1093/jnen/nly043 Published: 07 June 2018

DISCUSSION

This is the first report of presumed sporadic CJD occurring in a person who married into a GSS family. The estimated prevalence of GSS is in the range of 2–5 per 100 million people worldwide, and the annual mortality rate for sCJD in Denmark is 1.46 per 1 million people (31). The population of Denmark consists of 5 740 185 individuals, and there are 2 registered GSS cases that belong to the same family. The Danish GSS family is only the thirty-fourth known GSS family in the world (32). One could assume that the risk for a Danish man with GSS to have a wife or a mother who would develop CJD in her seventies is as high as for any other man. On the basis of the mortality rate for sCJD, and assuming that the incidence of sCJD is the same among married and unmarried people, we could state that 1 man out of 684 932 men has a risk of marrying a woman who would develop CJD. However, in this case, the man a priori had GSS, which means that it would take 1 man out of 684 932 men with GSS for such a pairing to occur. Considering the worldwide rarity of GSS cases, the likelihood for co-occurrence of GSS and sCJD in one family is hence very low and warrants an investigation for the possible transmission of prions routes.


Volume 25, Number 1—January 2019

Research

Variable Protease-Sensitive Prionopathy Transmission to Bank Vol

Romolo Nonno1, Silvio Notari1, Michele Angelo Di Bari, Ignazio Cali, Laura Pirisinu, Claudia d’Agostino, Laura Cracco, Diane Kofskey, Ilaria Vanni, Jody Lavrich, Piero Parchi, Umberto Agrimi, and Pierluigi GambettiComments to Author 

Author affiliations: Istituto Superiore di Sanità, Rome, Italy (R. Nonno, M.A. Di Bari, L. Pirisinu, C. d’Agostino, I. Vanni, U. Agrimi); Case Western Reserve University, Cleveland, Ohio, USA (S. Notari, I. Cali, L. Cracco, D. Kofskey, J. Lavrich, P. Gambetti); University of Bologna, Bologna, Italy (P. Parchi); Istituto delle Scienze Neurologiche di Bologna, Bologna (P. Parchi)

***> However, the VPSPr prion shares the multiplicity of the resPrPD electrophoretic bands with prions from a subset of inherited prion diseases referred to as Gerstmann-Sträussler-Scheinker disease (GSS), prompting the suggestion that VPSPr is the sporadic form of GSS (7,10). Furthermore, the presence of small amounts of sCJD-like 3-band resPrPD has also been signaled in VPSPr (6,11,12).


Subject: CWD GSS TSE PRION SPINAL CORD, Confucius Ponders, What if?

Saturday, February 2, 2019 

CWD GSS TSE PRION SPINAL CORD, Confucius Ponders, What if?

snip... 

 ***> In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids.'' Scientific opinion on chronic wasting disease (II) <*** 

REVIEW 

***> In conclusion, sensory symptoms and loss of reflexes in Gerstmann-Sträussler-Scheinker syndrome can be explained by neuropathological changes in the spinal cord. We conclude that the sensory symptoms and loss of lower limb reflexes in Gerstmann-Sträussler-Scheinker syndrome is due to pathology in the caudal spinal cord. <***

***> The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology.<*** 

***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD. <***

***> All animals have variable signs of prion neuropathology in spinal cords and brains and by supersensitive IHC, reaction was detected in spinal cord segments of all animals.<*** 

***> In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids.'' Scientific opinion on chronic wasting disease (II) <***

Thursday, March 8, 2018 

Familial human prion diseases associated with prion protein mutations Y226X and G131V are transmissible to transgenic mice expressing human prion protein


Saturday, February 2, 2019 

CWD GSS TSE PRION SPINAL CORD, Confucius Ponders, What if?


FRIDAY, JANUARY 31, 2020 

CJD TSE Prion Blood Products, iatrogenic transmission, Confucius is confused again, WHAT IF? Docket Number: FDA-2012-D-0307


THURSDAY, JANUARY 30, 2020 

Docket Number: FDA-2012-D-0307 Recommendations to Reduce the Possible Risk of Transmission of Creutzfeldt-Jakob Disease and Variant Creutzfeldt-Jakob Disease by Blood and Blood Components; Draft Guidance for Industry Draft Guidance for Industry Singeltary Submission


THURSDAY, SEPTEMBER 26, 2019 

Veterinary Biologics Guideline 3.32E: Guideline for minimising the risk of introducing transmissible spongiform encephalopathy prions and other infectious agents through veterinary biologics


WEDNESDAY, DECEMBER 04, 2019 

Three Cases of Creutzfeldt-Jakob Disease with Visual Disturbances as Initial Manifestation


Friday, September 27, 2019

Prion disease and recommended procedures for flexible endoscope reprocessing – a review of policies worldwide and proposal for a simplified approach


THURSDAY, SEPTEMBER 26, 2019 

Veterinary Biologics Guideline 3.32E: Guideline for minimising the risk of introducing transmissible spongiform encephalopathy prions and other infectious agents through veterinary biologics


SATURDAY, SEPTEMBER 21, 2019 

National Variability in Prion Disease–Related Safety Policies for Neurologic Procedures


Wednesday, September 11, 2019 

Is the re-use of sterilized implant abutments safe enough? (Implant abutment safety) iatrogenic TSE Prion


FRIDAY, SEPTEMBER 06, 2019 

Disinfection of Multi-Use Ocular Equipment for Ophthalmological Procedures: A Review of Clinical Effectiveness, Cost-Effectiveness, and Guidelines


MONDAY, AUGUST 26, 2019

Creutzfeldt Jakob Disease CJD, TSE, Prion, Surveillance Update August 2019


SUNDAY, MARCH 10, 2019 

National Prion Disease Pathology Surveillance Center Cases Examined¹ Updated Feb 1, 2019 Variably protease-sensitive prionopathy VPSPr


Sporadic Creutzfeldt-Jakob Disease in 2 Plasma Product Recipients, United Kingdom 

Volume 23, Number 6—June 2017 Synopsis

Sporadic Creutzfeldt-Jakob Disease in 2 Plasma Product Recipients, United Kingdom, P. Urwin et al.

View Summary

Two cases of sporadic CJD with clotting disorders have been identified, but this may represent a chance event. 

Patrick Urwin, Kumar Thanigaikumar, James W. Ironside, Anna Molesworth, Richard S. Knight, Patricia E. Hewitt, Charlotte Llewelyn, Jan Mackenzie, and Robert G. Will

Comments to Author Author affiliations: University of Edinburgh Western General Hospital, Edinburgh, Scotland, UK (P. Urwin, J.W. Ironside, A. Molesworth, R.S. Knight, J. Mackenzie, R.G. Will); University Hospital Lewisham, London, UK (K. Thanigaikumar); National Health Service Blood and Transplant, London (P.E. Hewitt); National Health Service Blood and Transplant/Public Health England Epidemiology Unit, Cambridge, UK (C. Llewelyn) Cite This Article

Introduction

CME Logo In support of improving patient care, this activity has been planned and implemented by Medscape, LLC and Emerging Infectious Diseases. Medscape, LLC is jointly accredited by the Accreditation Council for Continuing Medical Education (ACCME), the Accreditation Council for Pharmacy Education (ACPE), and the American Nurses Credentialing Center (ANCC), to provide continuing education for the healthcare team.

Medscape, LLC designates this Journal-based CME activity for a maximum of 1.00 AMA PRA Category 1 Credit(s)™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

All other clinicians completing this activity will be issued a certificate of participation. To participate in this journal CME activity: (1) review the learning objectives and author disclosures; (2) study the education content; (3) take the post-test with a 75% minimum passing score and complete the evaluation at http://www.medscape.org/journal/eid  and (4) view/print certificate.

Release date: May 12, 2017; Expiration date: May 12, 2018

Learning Objectives Upon completion of this activity, participants will be able to:

• Recognize the clinical features of 2 cases of sporadic Creutzfeldt-Jakob disease (sCJD) reported in patients with clotting disorders treated with fractionated plasma products.

• Identify the laboratory and pathology findings of 2 cases of sCJD reported in patients with clotting disorders treated with fractionated plasma product.

• Determine the clinical implications of 2 cases of sCJD reported in patients with clotting disorders treated with fractionated plasma products.

CME Editor Jude Rutledge, BA, Technical Writer/Editor, Emerging Infectious Diseases. Disclosure: Jude Rutledge has disclosed no relevant financial relationships.

CME Author Laurie Barclay, MD, freelance writer and reviewer, Medscape, LLC. Disclosure: Laurie Barclay, MD, has disclosed the following relevant financial relationships: owns stock, stock options, or bonds from Alnylam; Biogen; Pfizer.

Authors Disclosures: Patrick Urwin, MBBS, MA (CANTAB); Kumar Thanigaikumar, MBBS, MRCP, FRCPATH; James W. Ironside, MD; Anna Molesworth, PhD; Patricia E. Hewitt, MD, FRCPATH; Charlotte A. Llewelyn, PhD; and Jan Mackenzie, PG Cert Epidemiology, have disclosed no relevant financial relationships. Richard S. Knight, BMBCh, FRCP (E), has disclosed the following relevant financial relationships: served as a speaker or a member of a speakers bureau for Pfizer Inc. Robert G. Will, MD, has disclosed the following relevant financial relationships: served as an advisor or consultant for LFB (Paris); Ferring Pharmaceuticals.

Abstract

Sporadic Creutzfeldt-Jakob disease (sCJD) has not been previously reported in patients with clotting disorders treated with fractionated plasma products. We report 2 cases of sCJD identified in the United Kingdom in patients with a history of extended treatment for clotting disorders; 1 patient had hemophilia B and the other von Willebrand disease. Both patients had been informed previously that they were at increased risk for variant CJD because of past treatment with fractionated plasma products sourced in the United Kingdom. However, both cases had clinical and investigative features suggestive of sCJD. This diagnosis was confirmed in both cases on neuropathologic and biochemical analysis of the brain. A causal link between the treatment with plasma products and the development of sCJD has not been established, and the occurrence of these cases may simply reflect a chance event in the context of systematic surveillance for CJD in large populations.

Discussion This report describes 2 cases of sCJD in patients with a history of treatment with UK-sourced plasma products, 1 with a history of hemophilia B and 1 with von Willebrand’s disease. To our knowledge, no previous case of sCJD in a person with a history of extended exposure to plasma products has been reported. It is clearly of concern that there have been 2 such cases in a relatively short period in the UK, where many plasma product recipients have been informed that they are at increased risk for vCJD. However, a causal link between the treatment with plasma products and the onset of sCJD has not been established, and the occurrence of these cases may simply reflect a chance event in the context of systematic surveillance of CJD in large populations.

Both patients had been informed that they were at increased risk for vCJD, and considering the evidence for the type of CJD in the 2 cases is important. Both patients had a clinical phenotype suggestive of sCJD, including a short duration of illness, typical early symptoms, a suggestive MRI scan, and, in 1 patient, a typical EEG. Notably, both patients had a positive real-time quaking-induced conversion test result for PrPSc in CSF; previously this test had not been positive in any case of vCJD evaluated in our laboratory (Table 2) (9). However, neuropathological examination was critical; it showed appearances typical of sCJD in both patients and no evidence of peripheral pathogenesis on immunostaining of lymphoreticular tissues, a feature that is observed in all tested specimens of vCJD patients to date (10). Furthermore, both patients had a type 1A isoform PrPSc on Western blot consistent with a diagnosis of sCJD subtype MM1 (11). Neither patient had a history of potential iatrogenic exposure or a family history of CJD, and for the case for which sequencing of the PRNP was performed, no mutations were detected. In both cases, an MM genotype occurred at codon 129 of PRNP, which does not distinguish between sCJD and vCJD. Laboratory transmission studies to provide evidence of agent strain in the cases have not been possible.

One patient had received multiple transfusions of blood components over an extended period, and the other had received 6 units of FFP 19 years before clinical onset, raising the possibility that these cases could have resulted from secondary transmission through blood components. In the case of the patient with von Willebrand disease, 107 donors have been traced, and none appear in the register of cases of CJD kept at the National CJD Research and Surveillance Unit. However, it has not been possible to obtain information on blood transfusions for this patient before 2001 nor on the FFP transfusions for the patient with hemophilia B. Lookback studies in the United States and United Kingdom have provided no evidence of transfusion-transmission of sCJD (2,3), and although 1 study suggested an increase in risk after a lag period of 10 years (12), this finding was not confirmed in another study (13). The balance of evidence indicates that, if sCJD is transmitted by blood transfusion, it must be a rare event, if it happens at all, and transfusion transmission is probably not the explanation for the 2 cases we describe.

Systematic surveillance for CJD, including a coordinated study in Europe (14), has been carried out in many countries over the past 25 years and is continuing. Many of these studies obtain information on potential risk factors, including details of past medical history. To date, no case of sCJD has been reported in a person who has received treatment for a clotting disorder. In fact, the absence of such a case has been used to argue against the possibility that plasma-derived products pose a risk for sCJD transmission (6). CJD surveillance centers are aware of the relevance of this issue, and sCJD patients with a history of treatment with plasma products probably would have been identified and reported if they occurred. Although it is surprising that 2 cases of sCJD have been identified among a population of 4,000–5,000 patients in the UK who have been treated for clotting disorders with fractionated plasma products, the total population under surveillance for CJD in Europe and internationally exceeds 500 million. Assuming an annual incidence rate of sCJD of 1.5–2.0 per million population (15), the occurrence of 2 cases of sCJD in this total population may not imply a causal link between the treatment and the occurrence of the disease. The 2 cases were identified over a period of months, and no further cases have been found since 2014; however, continuing to search for such cases through CJD surveillance programs is essential.

Dr. Urwin worked as a research registrar at the National CJD Research and Surveillance Unit and is currently training in neurology. His primary research interests include human prion diseases.


Volume 23, Number 6—June 2017 Synopsis

Sporadic Creutzfeldt-Jakob Disease in 2 Plasma Product Recipients, United Kingdom, P. Urwin et al.

View Summary

Two cases of sporadic CJD with clotting disorders have been identified, but this may represent a chance event.


''A causal link between the treatment with plasma products and the development of sCJD has not been established, and the occurrence of these cases may simply reflect a chance event in the context of systematic surveillance for CJD in large populations.'' 

???

>>>They found infectivity in the red and white blood cells and plasma of a variant CJD patient and in the plasma of two of four sporadic CJD patients tested. These findings indicate the need to continue assessing the possible risk for CJD transmission via transfusion of blood products.<<< 

>>>In tgBov inoculated with vCJD and tgHu inoculated with sCJD, the PrPres banding patterns observed by Western blot in animals challenged with brain homogenate and blood components were identical (Figure, panels C, D). These results support the contention that the TSE agent propagated in tgBov mice and tgHu were vCJD and sCJD agents, respectively.<<< 


Tuesday, November 29, 2016 

Transmissibility of Gerstmann–Sträussler–Scheinker syndrome in rodent models: new insights into the molecular underpinnings of prion infectivity 


FRIDAY, APRIL 21, 2017 

Distribution and Quantitative Estimates of Variant Creutzfeldt-Jakob Disease Prions in Tissues of Clinical and Asymptomatic Patients


MONDAY, NOVEMBER 23, 2015 

Blood transmission studies of prion infectivity in the squirrel monkey (Saimiri sciureus): the Baxter study ORIGINAL RESEARCH 

Blood transmission studies of prion infectivity in the squirrel monkey (Saimiri sciureus): the Baxter study

Diane L. Ritchie1,*, Susan V. Gibson2,†, Christian R. Abee3, Thomas R. Kreil4, James W. Ironside1 and Paul Brown5

Article first published online: 23 NOV 2015

DOI: 10.1111/trf.13422

© 2015 AABB

Issue

Cover image for Vol. 55 Issue 11

Transfusion

Early View (Online Version of Record published before inclusion in an issue)

Abstract

BACKGROUND

Four secondary transmissions of variant Creutzfeldt-Jakob disease (vCJD) infectivity have been associated with the transfusion of nonleukoreduced red blood cells collected from vCJD patients during the asymptomatic phase of the disease. Establishing efficient experimental models for assessing the risk of future transmissions of vCJD infectivity via blood transfusion is of paramount importance in view of a study of archived appendix samples in which the prevalence of asymptomatic vCJD infection in the United Kingdom was estimated at approximately 1 in 2000 of the population. In this study, we investigated transmission of vCJD and sporadic CJD (sCJD) infectivity from blood using the squirrel monkey, which is highly susceptible to experimental challenge with human prion disease.

STUDY DESIGN AND METHODS

Whole blood collected from vCJD- and sCJD-infected squirrel monkeys was transfused at multiple time points into recipient squirrel monkeys. Blood recipients were euthanized approximately 7 years after their first blood transfusion.

RESULTS

No clinical or pathologic signs of a prion disease were observed in either the sCJD- or the vCJD-transfused monkeys, and immunohistochemistry and biochemical investigations showed no PrPTSE in central nervous system or lymphoreticular tissues. Similarly, monkeys inoculated intracerebrally (IC) and intravenously (IV) with either buffy coat or plasma from vCJD and sCJD patients failed to develop disease. However, white blood cells from a chimpanzee-passaged strain of human Gerstmann-Sträussler-Scheinker (GSS) disease transmitted autopsy-proven disease to two IC-inoculated monkeys after incubation periods of 34 and 39 months.

CONCLUSION

Blood transmits GSS but not sCJD or vCJD infectivity to IC- or IV-inoculated squirrel monkeys within a 7-year observation period.


2015 PRION CONFERENCE

*** RE-P.164: Blood transmission of prion infectivity in the squirrel monkey: The Baxter study

***suggest that blood donations from cases of GSS (and perhaps other familial forms of TSE) carry more risk than from vCJD cases, and that little or no risk is associated with sCJD. ***

P.164: Blood transmission of prion infectivity in the squirrel monkey: The Baxter study

Paul Brown1, Diane Ritchie2, James Ironside2, Christian Abee3, Thomas Kreil4, and Susan Gibson5 1NIH (retired); Bethesda, MD USA; 2University of Edinburgh; Edinburgh, UK; 3University of Texas; Bastrop, TX USA; 4Baxter Bioscience; Vienna, Austria; 5University of South Alabama; Mobile, AL USA 

Five vCJD disease transmissions and an estimated 1 in 2000 ‘silent’ infections in UK residents emphasize the continued need for information about disease risk in humans. A large study of blood component infectivity in a non-human primate model has now been completed and analyzed. Among 1 GSS, 4 sCJD, and 3 vCJD cases, only GSS leukocytes transmitted disease within a 5–6 year surveillance period. A transmission study in recipients of multiple whole blood transfusions during the incubation and clinical stages of sCJD and vCJD in ic-infected donor animals was uniformly negative. These results, together with other laboratory studies in rodents and nonhuman primates and epidemiological observations in humans, suggest that blood donations from cases of GSS (and perhaps other familial forms of TSE) carry more risk than from vCJD cases, and that little or no risk is associated with sCJD. The issue of decades-long incubation periods in ‘silent’ vCJD carriers remains open. 


Friday, December 04, 2015

Iatrogenic and sporadic Creutzfeldt-Jakob disease in two sisters without mutation in the prion protein gene


Friday, December 04, 2015

Iatrogenic and sporadic Creutzfeldt-Jakob disease in two sisters without mutation in the prion protein gene


SUNDAY, MAY 10, 2009

Meeting of the Transmissible Spongiform Encephalopathies Committee On June 12, 2009 (Singeltary submission)


May 8, 2009

Greetings again Dr. Freas, TSEAC et al,

I would kindly, once again, wish to comment at this meeting about the urgent actions that need to be taken asap, to the Meeting of the Transmissible Spongiform Encephalopathies Committee On June 12, 2009. Due to my disability from my neck injury, I will not be attending this meeting either, however I hope for my submission to be read and submitted. ...

IN reply to ;

Meeting of the Transmissible Spongiform Encephalopathies Committee Center Date Time Location CBER June 12, 2009 June 12, 2009 from 8:00 a.m. to 5:45 p.m. Holiday Inn Gaithersburg, Grand Ballroom, 2 Montgomery Village Ave. Gaithersburg, Maryland 20879

Agenda On June 12, 2009, the Committee will review and discuss a recent report from the UK Health Protection Agency attributing a case of variant Creutzfeldt-Jakob (vCJD) disease infection to treatment 11 years earlier with a "vCJD-implicated" plasma-derived coagulation factor VIII (pdFVIII) and whether this information or any other recent scientific information about the vCJD epidemic substantially alters FDA's risk assessment for US-licensed preparations of pdFVIII products. In the afternoon the committee will hear informational presentations on animal models of vCJD, diagnostic test development for transmissible spongiform encephalopathies (TSEs) and bovine spongiform encephalopathy (BSE) surveillance and risk management. ...snip...end

* Written submissions may be made to the contact person on or before June 4, 2009.


My written submission as follows ;

BY lumping all CJD's as sporadic, as one strain, of young and old here in the USA, with all the different TSEs in the bovine in North America i.e. c-BSE, h-BSE, and l-BSE, CWD in deer and elk spreading, Scrapie AND the atypical Nor-98 spreading, and then claiming all of them to be of a 'spontaneous' nature, we are still in cover-up mode for mad cow disease and any human TSE thereof in North America, and any consumer of blood products from humans here in the USA that are exposed to these animal TSE via a multitude of routes and sources, needlessly exposes these consumers to these Transmissible Spongiform Encephalopathies.

YOU first have to have a CJD surveillance system that is in place, in all states, of all age groups, with a written cjd questionnaire going out to all victims and their families asking REAL questions pertaining to route and source of agent. with proper transmission studies done on all phenotypes of human TSE. until then, this study means nothing.

NOW, I know what your thinking (FDA), your thinking that present regulations in place will be sufficient.

I kindly disagree for the following reasons ;

1. atypical Transmissible Spongiform Encephalopathy in North America. we simply do NOT know how wide spread these atypical TSE are, considering the totally flawed policy of the 'Enhanced BSE surveillance Program' several years back. it was proven to be so by the GOA, OIG, and Dr. Paul Brown of the CDC confirmed it by his own words, and the industry has proven it by the total disregard of current and past regulations (no matter how weak they were). for this reason alone, the FDA cannot assure that the products in question are safe and free of the TSE Prion agent, to be passed to expose others in the years to come vie 'friendly fire' i.e. the medical, surgical, and or dental arena. ...

2. some sub-types of atypical BSE seem to be more virulent than the typical c-BSE. all of which have been documented in North America i.e. c-BSE, h-BSE, and the l-BSE. Scapie (typical and atypical Nor-98), and CWD (with an apparent second strain, the Wisconsin Variant CWD). With all these animal TSEs in North America, and the potential transmission to humans via deer, elk, sheep, goat, cattle, via a multitude of proven routes and sources (proven in the lab and in the field), to ignore the limited science to date, and continue to peddle USA blood and blood products as a safe product, in my opinion, and I have said it before, it's like playing Russian Roulette with the consumers that must use these blood and blood products. ...

3. the FDA et al have been hiding behind false fictitious firewalls, the previous partial and voluntary ruminant to ruminant feed ban, and the Enhanced BSE surveillance program, where some 800,000 cattle were tested. BOTH of which were proven to be totally flawed. To a point of criminal intent in my opinion. ...

4. several studies I would kindly like to bring to your attention below, on why I stringently urge this committee, once again, to ban all humans from past history of any TSE (family members included) from giving blood. it would also seem prudent to update and enhance the questionnaire for donors of blood, blood products, and tissue donors, and strictly enforce these regulations. just look at past history, and all the bad blood out there from suspect human nvCJD alone, let alone donors that consume potentially tainted products, including dietary nutritional supplements that contain SRMs or 'antler velvet' from either deer or elk (see May 2009 CDC warning on this). look at the weekly recalls, from blood that has been distributed all around the globe, from a faulty regulated product, via a faulty screening program. see for yourself, don't take my word for it, but then think of the 'friendly fire' issues there of, in the years, decades to come, while continuing to kid yourself about the sporadic/spontaneous CJD's. all the while, it seems that some of these human and animal TSE's, when mutated, become more virulent. you continue to roll the dice, or being ''asleep at the wheel'', as you have been in the past (my opinion), you will continue to needlessly expose and possibly kill many more humans due to this lax regulatory system, and in time, find yourself in a much worse situation that the U.K. and E.U. are now in. ...

P23

EXPRESSION OF PRION PROTEIN ON BLOOD CELLS OF HEALTHY AND TSE INFECTED CYNOMOLGUS MACAQUES

Janouskova O1, Vranac T2, Glierova H1, Comoy EE3, Curin Serbec V2, Deslys JP3, Holada K1 1Institute of Immunology and Microbiology, 1st Faculty of Medicine, Charles University, Praque, Czech Republic; 2Blood Transfusion Centre of Slovenia, Ljubljana, Slovenia; 3Institute of Emerging Diseases and Innovative Therapies, CEA, Fontenay-aux-Roses, France

Transmissibility of TSE in experimental animals by intravenous inoculation is well documented. Ability of blood to transmit TSE was recently confirmed by four secondary vCJD infections in recipients of blood transfusion. This demonstrated the risk associated with blood transfusion and raised concerns about undetected subclinical vCJD in the donor population.

Very little is known about the nature and behavior of prions in blood. In animal models TSE infectivity seems to be distributed between plasma and blood cells in the ratio near to 1:1. The cell associated infectivity appears to concentrate in leukocytes, while its association with red cells and platelets seems to be quite limited. Detection of pathological prion protein (PrPtse) in blood is complicated by the presence of substantial amount of poorly characterized cellular prion protein (PrPc) and by unavailability of PrPtse specific antibodies.

In the present study, we have used anti-PrP monoclonal antibodies and three color flow cytometry to investigate expression or exposition of epitopes of prion protein on intact and permeabilized dendritic cells (DC) and monocytes (MC) in healthy and BSE/vCJD infected cynomolgus macaques (Macaca fascicularis). First group of animals was infected i.v. with macaque BSE brain homogenate (5 animals, 2 were 39 month post infection, 3 were 33 month post infection). Second group was infected i.v. with macaque vCJD brain homogenate (6 animals, 3 were 27 month post infection and 3 were 21 month post infection). All animals were positive for the presence of PrPtse in lymph nodes by IHC. Two antibody panels were used (DC, MC). DC were defined as lineage markers negative (CD3, CD8, CD14, CD20) and HLA-DR positive cells. MC were defined as CD14 and HLA-DR positive cells.

Four different prion monoclonal antibodies (AG4, 3F4, AH6, V5B2) were used. The antibody AG4 binds to the N-terminal part of PrP. The antibody 3F4 binds to the central part of PrP. The AH6 epitope is located on the C-terminal part of PrP. MAb V5B2 was developed against a C-terminal PrP peptide and was shown to specifically recognize human PrPtse by diverse methods (Serbec et al. J. Biol. Chem 2004, 279, 3694-98).

Permeabilization protocol for intracellular detection of prion protein was optimized to allow detection of intracellular PrPc/PrPtse by all antibodies used. Fixation and permeabilization led to decrease of PrP detection with 3F4 and AG4 in the contrast to its increase with AH6 and V5B2. While the differences in binding of MAbs to cells of healthy and infected animals did not reach statistical significance, we observed significant difference in exposition of epitopes between MC and DC in vCJD infected monkeys in contrast with healthy monkeys. The diference was detected by AH6, 3F4, AG4 on intact cells and by 3F4 and AG4 in permeabilized cells.

Information on the presence of PrPc/PrPtse after permeabilization of MC and DC, together with demonstration of significant difference in the exposition of PrP epitopes between MC and DC in vCJD group in contrast to healthy controls might be relevant to the pathology of prion diseases and may help to facilitate TSE diagnosis.


explain then about GSS and blood and the potential risk thereof ???

FC5.1.1 Transmission Results in Squirrel Monkeys Inoculated with Human sCJD, vCJD, and GSS Blood Specimens: the Baxter Study

Brown, P1; Gibson, S2; Williams, L3; Ironside, J4; Will, R4; Kreil, T5; Abee, C3 1Fondation Alliance BioSecure, France; 2University of South Alabama, USA; 3University of Texas MD Anderson Cancer Center, USA; 4Western General Hospital, UK; 5Baxter BioSience, Austria

Background: Rodent and sheep models of Transmissible Spongiform Encephalopathy (TSE) have documented blood infectivity in both the pre-clinical and clinical phases of disease. Results in a (presumably more appropriate) non-human primate model have not been reported. Objective: To determine if blood components (red cells, white cells, platelets, and plasma) from various forms of human TSE are infectious. Methods: Blood components were inoculated intra-cerebrally (0.1 ml) and intravenously (0.5 ml) into squirrel monkeys from 2 patients with sporadic Creutzfeldt- Jakob disease (sCJD) and 3 patients with variant Creutzfeldt-Jakob disease (vCJD). Additional monkeys were inoculated with buffy coat or plasma samples from chimpanzees infected with either sCJD or Gerstmann-Sträussler-Scheinker disease (GSS). Animals were monitored for a period of 5 years, and all dying or sacrificed animals had post-mortem neuropathological examinations and Western blots to determine the presence or absence of the misfolded 'prion' protein (PrPTSE). Results: No transmissions occurred in any of the animals inoculated with blood components from patients with sporadic or variant CJD. All donor chimpanzees (sCJD and GSS) became symptomatic within 6 weeks of their pre-clinical phase plasmapheresis, several months earlier than the expected onset of illness. One monkey inoculated with purified leukocytes from a pre-clinical GSS chimpanzee developed disease after 36 months. Conclusion: No infectivity was found in small volumes of blood components from 4 patients with sporadic CJD and 3 patients with variant CJD.

***However, a single transmission from a chimpanzee-passaged strain of GSS shows that infectivity may be present in leukocytes, and the 'shock' of general anaesthesia and plasmspheresis appears to have triggered the onset of illness in pre-clinical donor chimpanzees.

===================================

FC5.1.2 Interim Transmission Results in Cynomolgus Macaques Inoculated with BSE and vCJD Blood Specimens

Lasmezas, C1; Lescoutra, N2; Comoy, E2; Holznagel, E3; Loewer, J3; Motzkus, D4; Hunsmann, G4; Ingrosso, L5; Bierke, P6; Pocchiari, M5; Ironside, J7; Will, R7; Deslys, JP2 1Scripps Florida, Infectology, USA; 2CEA, France; 3PEI, Germany; 4DPZ, Germany; 5Istituto Superiore di Sanita, Italy; 6SMI, Sweden; 7CJD Surveillance Unit, UK

BSE and vCJD transmitted to cynomolgus macaques reproduce many features of human vCJD, including clinical symptoms, neuropathological hallmarks of vCJD, PrPres electrophoretical pattern and, most importantly, the wide distribution of infectivity in peripheral organs. The latter characteristic distinguishes vCJD from sCJD in both humans and cynomolgus macaques, and prompted us to use this non-human primate model for further investigations of vCJD and its risk for human health. The occurrence of four vCJD infections in humans transfused with blood from patients who later developed vCJD has raised concern about blood transfusion safety in countries with vCJD. In this collaborative European study, we investigated the infectivity of blood components and whole blood administered by intracerebral (ic) and intravenous (iv) routes. Buffy-coat and whole blood was inoculated by ic and iv route, respectively, from two vCJD patients and from two clinical vCJD-inoculated macaques. Transfusions were also performed from whole blood and blood leucodepleted according to hospital practice standards from two clinical BSE inoculated macaques. Blood infectivity during the preclinical phase is being examined in orally infected macaques. Whole blood was collected and transfused from one such animal two years after oral challenge, whereas buffy-coat and plasma from two animals at 2 and 4.5 years post-challenge, respectively, have been inoculated by the ic route. This is an ongoing study in which recipient animals continue to be observed at various times post-inoculation. So far, we have had one positive transmission in one animal transfused 65 months earlier with 40 ml of whole blood from a vCJD macaque (the characteristics of the disease in this animal will be shown in a separate poster by E. Comoy). This positive transmission reproduces transfusion transmission of vCJD in humans, with an incubation of 5.5 years compatible with incubation periods observed in humans.

===================================

see full text 143 pages ;


snip...see full text;


TSS TO FREAS TSEAC 2001 CJD BLOOD ISSUES

Freas, William

From:Terry S. Singeltary Sr. [flounder@wt.net]

Sent: Monday, January 08, 200l 3:03 PM

To: mhtml:%7B33B38F65-8D2E-434D-8F9B-8BDCD77D3066%7Dmid://00000039/!x-usc:mailto:freas@CBS5055530.CBER.FDA.GOV

Subject:CJD, BSE (aka madcow) Human/Animal TSE's--U.S.--Submission To Scientific Advisors and Consultants Staff January 2001 Meeting (short version)

Greetings again Dr. Freas and Committee Members,

I wish to submit the following information to the Scientific Advisors and Consultants Staff 2001 Advisory Committee (short version).

I understand the reason of having to shorten my submission, but only hope that you add it to a copy of the long version, for members to take and read at their pleasure, (if cost is problem, bill me, address below). So when they realize some time in the near future of the 'real' risks i speak of from human/animal TSEs and blood/surgical products. I cannot explain the 'real' risk of this in 5 or 10 minutes at some meeting, or on 2 or 3 pages, but will attempt here:

remember AIDS/HIV, 'no problem to heterosexuals in the U.S.? no need to go into that, you know of this blunder:

DO NOT make these same stupid mistakes again with human/animal TSE's aka MADCOW DISEASE. I lost my Mom to hvCJD, and my neighbor lost his Mother to sC3D as well (both cases confirmed). I have seen many deaths, from many diseases. I have never seen anything as CJD, I still see my Mom laying helpless, jerking tremendously, and screaming "God, what's wrong with me, why can't I stop this". I still see this, and will never forget. Approximately 10 weeks from 1st of symptoms to death. This is what drives me. I have learned more in 3 years about not only human/animal TSE's but the cattle/rendering/feeding industry/government than i ever wished to.

I think you are all aware of CJD vs vCJD, but i don't think you all know the facts of human/animal TSE's as a whole, they are all very very similar, and are all tied to the same thing, GREED and MAN.

I am beginning to think that the endless attempt to track down and ban, potential victims from known BSE Countries from giving blood will be futile. You would have to ban everyone on the Globe eventually? AS well, I think we MUST ACT SWIFTLY to find blood test for TSE's, whether it be blood test, urine test, .eyelid test, anything at whatever cost, we need a test FAST.

DO NOT let the incubation time period of these TSEs fool you.

To think of Scrapie as the prime agent to compare CJD, but yet overlook the Louping-ill vaccine event in 1930's of which 1000's of sheep where infected by scrapie from a vaccine made of scrapie infected sheep brains, would be foolish. I acquired this full text version of the event which was recorded in the Annual Congress of 1946 National Vet. Med. Ass. of Great Britain and Ireland. from the BVA and the URL is posted in my (long version).

U.S.A. should make all human/animal TSE's notifiable at all ages, with requirements for a thorough surveillance and post-mortem examinations free of charge, if you are serious about eradicating this horrible disease in man and animal.

There is histopathology reports describing o florid plaques" in CJD victims in the USA and some of these victims are getting younger. I have copies of such autopsies, there has to be more. PLUS, sub-clinical human TSE's will most definitely be a problem.

THEN think of vaccineCJD in children and the bovine tissues used in the manufacturing process, think of the FACT that this agent surviving 6OO*C.

PNAS -- Brown et al. 97 (7): 3418 scrapie agent live at 600*C

Then think of the CONFIDENTIAL documents of what was known of human/animal TSE and vaccines in the mid to late 8Os, it was all about depletion of stock, to hell with the kids, BUT yet they knew. To think of the recall and worry of TSE's from the polio vaccine, (one taken orally i think?), but yet neglect to act on the other potential TSE vaccines (inoculations, the most effective mode to transmit TSEs) of which thousands of doses were kept and used, to deplete stockpile, again would be foolish.

--Oral polio; up to 1988, foetal calf serum was used from UK and New Zealand (pooled); since 1988 foetal calf serum only from New Zealand. Large stocks are held.

--Rubella; bulk was made before 1979 from foetal calf serum from UK and New Zealand. None has been made as there are some 15 years stock.

--Diphtheria; UK bovine beef muscle and ox heart is used but since the end of 1988 this has been sourced from Eire. There are 1,250 litres of stock.

--Tetanus; this involves bovine material from the UK mainly Scottish. There are 21,000 litres of stock.

--Pertussis; uses bovine material from the UK. There are 63,000 litres of stock.

--They consider that to switch to a non-UK source will take a minimum of 6-18 months and to switch to a non-bovine source will take a minimum of five years.

3. XXXXXXXXXXX have measles, mumps, MMR, rubella vaccines. These are sourced from the USA and the company believes that US material only is used.

89/2.14/2.1

============

BSE3/1 0251

4. XXXXXXXXXXX have a measles vaccine using bovine serum from the UK. there are 440,000 units of stock. They have also got MMR using bovine serum from the UK.

5. XXXXXXXXXXX have influenza, rubella, measles,' MMR vaccines likely to be used in children. Of those they think that only MMR contains bovine material which is probably a French origin.

6. XXXXXXXXXXX have diphtheria/tetanus and potasses on clinical trial. hese use veal material, some of which has come from the UK and has been ade by XXXXXXXXXXX (see above).

I have documents of imports from known BSE Countries, of ferments, whole blood, antiallergenic preparations, human blood plasma, normal human blood sera, human immune blood sera, fetal bovine serum, and other blood fractions not elsewhere specified or included, imported glands, catgut, vaccines for both human/animal, as late as 1998.

Let us not forget about PITUITARY EXTRACT. This was used to help COWS super ovulate. This tissue was considered to be of greatest risk of containing BSE and consequently transmitting the disease.

ANNEX 6

MEETING HELD ON 8 JUNE 1988 TO DISCUSS THE IMPLICATIONS OF BSE TO BIOLOGICAL PRODUCTS CONTAINING BOVINE - EXTRACTED MATERIAL

How much of this was used in the U.S.?

Please do not keep making the same mistakes;

'Absence of evidence is not evidence of absence'.

What are the U.S. rules for importing and manufacturing vaccines, medicines and medical devices?

Does the U.S.A. allow sourcing of raw material of ruminants from the U.S.A.?

U.S. cattle, what kind of guarantee can you give for serum or tissue donor herds.?

The U.S. rendering system would easily amplify T.S.E.'s:

Have we increased the stability of the system (improved heat treatments) since the EU SSC report on the U.S.A. was published in july 2000?

What is done to avoid cross-contaminations in the U.S.A.?

How can the U.S. control absence of cross-contaminations of animal TSE's when pig and horse MBM and even deer and elk are allowed in ruminant feed, as well as bovine blood? I sadly think of the rendering and feeding policy before the Aug. 4, 1997 'partial' feed ban, where anything went, from the city police horse, to the circus elephant, i will not mention all the scrapie infected sheep. I am surprised that we have not included man 'aka soyent green'. It is a disgusting industry and nothing more than greed fuels it.

When will the U.S.. start real surveillance of the U.S. bovine population (not passive, this will not work)?

When will U.S. start removing SRMs?

Have they stopped the use of pneumatic stunners in the U.S.? If so, will we stop it in all U.S. abattoirs or only in those abattoirs exporting to Europe? If not, WHY NOT?

same questions for removal of SRM in the U.S.A., or just for export? If not, WHY NOT?

How do we now sterilize surgical/dental instruments in the U.S.A.?

Where have we been sourcing surgical catgut? (i have copies of imports to U.S., and it would floor you)

When will re-usable surgical instruments be banned?

'Unregulated "foods" such as 'nutritional supplements' containing various extracts from ruminants, whether imported or derived from US cattle/sheep/cervids ("antler velvet" extracts!) should be forbidden or at least very seriously regulated. (neighbors Mom, whom also died from CJD, had been taking bovine based supplement, which contained brain, eye, and many other bovine/ovine tissues for years, 'IPLEX').

What is the use of banning blood or tissue donors from Germany, France, etc... when the U.S.A. continues exposing cattle, sheep and people to SRM, refuses to have a serious feed ban, refuses to do systematic BSE-surveillance?

The FDA should feel responsible for the safety of what people eat, prohibit the most dangerous foods, not only prohibit a few more donors - the FDA should be responsible for the safe sourcing of medical devices, not only rely on banning donors "from Europe", The 'real' risks are here in the U.S. as well, and have been for some time.

We must not forget the studies that have proven infectivity in blood from TSE's.

The Lancet, November 9, 1985

Sir, --Professor Manuelidis and his colleagues (Oct 19, p896) report " transmission to animals of Creutzfeldt-Jakob disease (CJD) from the buffy coat from two patients. We also transmitted the disease from whole blood samples of a patient (and of mice) infected with CJD.l Brain, Cornea, and urine from this patient were also infectious, and the clinicopathological findings2 are summarised as follows.

snip...

Samples,were taken aseptically at necropsy. 10% crude homogenates of brain and cornea in saline, whole blood (after crushing a clot), and untreated CSF and urine were innoculated infracerebrally into CFl strain mice (20 ul per animal). Some mice showed emaciation, bradykinesia, rigidity of the body and tail, and sometimes tremor after long incubation periods. Tissues obtained after the animal died (or was killed) were studied histologically (table). Animals infected by various inocula showed common pathological changes, consisting of severe spongiform changes, glial proliferation, and a moderate loss of nerve cells. A few mice inoculated with brain tissue or urine had the same, amyloid plaques found in patients and animals with CJD.3

snip...

Department of Neuropathology, Neurological Institute, Faculty of Medicine, Kyushu University, Fukuoka812, Japan

JUN TATEISHI

(full text-long version)

and

CWD and transmission to man will be no different than other TSE's.

"Clearly, it is premature to draw firm conclusions about CWD passing naturally into humans, cattle and sheep, but the present results suggest that CWD transmissions to humans would be as limited by PrP incompatibility as transmissions of BSE or sheep scrapie to humans. Although there is no evidence that sheep scrapie has affected humans, it is likely that BSE has

4

caused variant CJD in 74 people (definite and probable variant CJD cases to date according to the UK CJD Surveillance Unit). Given the presumably large number of people exposed to BSE infectivity, the susceptibility of humans may still be very low compared with cattle, which would be consistent with the relatively inefficient conversion of human PrP-sen by PrPBSE. Nonetheless, since humans have apparently been infected by BSE, it would seem prudent to take reasonable measures to limit exposure of humans (as well as sheep and cattle) to CWD infectivity as has been recommended for other animal TSEs,"

G.J. Raymondl, A. BossersZ, L.D. Raymondl, K.I. O'Rourke3, L.E. McHolland4, P.K. Bryant 1114, M.W. MillerS, E.S. Williams6, M. Smits2 and B. Caugheyl,7

or more recently transmission of BSE to sheep via whole blood Research letters Volume 356, Number 9234 16 September 2000

Transmission of BSE by blood transfusion in sheep

Lancet 2000; 356: 999 - 1000

F Houston, J D Foster, Angela Chong, N Hunter, C J Bostock

See Commentary

"We have shown that it is possible to transmit bovine spongiform encephalopathy (BSE) to a sheep by transfusion with whole blood taken from another sheep during the symptom-free phase of an experimental BSE infection. BSE and variant Creutzfeldt-Jakob disease (vCJD) in human beings are caused by the same infectious agent, and the sheep-BSE experimental model has a similar pathogenesis to that of human vCJD. Although UK blood transfusions are leucodepleted--a possible protective measure against any risk from blood transmission-- this report suggests that blood donated by symptom-free vCJD-infected human beings may represent a risk of spread of vCJD infection among the human population of the UK."

. "The demonstration that the new variant of Creutzfeldt-Jakob disease (vCJD) is caused by the same agent that causes bovine spongiform encephalopathy (BSE) in cattle1 has raised concerns that blood from human beings in the symptom-free stages of vCJD could transmit infection to recipients of blood transfusions (full text long version)"

and...

"The large number of cases (1040), temporal clustering of the outbreaks (15 in the first 6 months of 1997), the high in-flock incidence, and the exceptional involvement of goats (390 cases), suggested an accidental infection. The source of the epidemic might have been TSE-contaminated meat and bonemeal, but eight flocks had never been fed any commercial feedstuff. Infection might have risen from the use of a formol-inactivated vaccine against contagious agalactia prepared by a single laboratory with brain and mammary gland homogenates of sheep infected with Mycoplasma agalactiae. Although clinical signs of TSE in the donor sheep have not been found, it is possible that one or more of them were harbouring the

infectious agent. Between 1995 and 1996, this vaccine was given subcutaneously to 15 of the affected flocks (to one flock in 1994) ; in these animals the disease appeared between 23 and 35 months after vaccination. No information is available for herd 13 because it was made up of stolen animals. Sheep from the remaining three flocks (l-3, figure) did not receive the vaccine, thus suggesting a naturally occurring disease." (again, full text long version).

IN SHORT, please do under estimate this data and or human/animal TSE's including CWD in the U.S.A.

A few last words, please.

The cattle industry would love to have us turn our focus to CWD and forget about our own home grown TSE in Bovines. This would be easy to do. Marsh's work was from downer cattle feed, NOT downer deer/elk feed. This has been proven.

DO NOT MAKE THAT MISTAKE.

There should be NO LESS THAN l,OOO,OOO tests for BSE/TSE in 2001 for U.S.A. French are testing 20,000 a week. The tests are available. Why wait until we stumble across a case from passive surveillance, by then it is to late. IF we want the truth, this is a must???

United States Total ,Bovine Brain Submissions by State,

May 10,1990 thru October 31, 2000

Total 11,700

FROM 1.5 BILLION HEAD OF CATTLE since 1990 ???

with same feeding and rendering practices as that of U.K. for years and years, same scrapie infected sheep used in feed, for years and years, 950 scrapie infect FLOCKS in the U.S. and over 20 different strains of scrapie known to date. (hmmm, i am thinking why there is not a variant scrapie, that is totally different than all the rest)? just being sarcastic. (NOT...TSS...2009)

with only PARTIAL FEED BAN implemented on Aug. 4, 1997??? (you really need to reconsider that blood meal etc. 'TOTAL BAN')


AND PLEASE FOR GODS SAKE, STOP saying vCJD victims are the only ones tied to this environmental death sentence. "PROVE IT". It's just not true. The 'CHOSEN ONES' are not the only ones dying because of this man-made death sentence. When making regulations for human health from human/animal TSEs, you had better include ALL human TSE's, not just vCJD. Do NOT underestimate sporadic CJD with the 'prehistoric' testing available to date. This could be a deadly mistake. Remember, sCJD kills much faster from 1st onset of symptoms to death, and hvCJD is the fastest. Could it just be a higher titre of infectivity, or route or source, or all three?

Last, but not least. The illegal/legal harvesting of body parts and tissues will come back to haunt you. Maybe not morally, but due to NO background checks and human TSEs, again it i will continue to spread.

Stupidity, Ignorance and Greed is what fuels this disease. You must stop all of this, and ACT AT ONCE...


ran across an old paper from 1984 ;

***The occurrence of contact cases raises the possibility that transmission in families may be effected by an unusually virulent strain of the agent. ***


From: Terry S. Singeltary Sr.

Sent: Saturday, November 15, 2014 9:29 PM

To: Terry S. Singeltary Sr.

Subject: THE EPIDEMIOLOGY OF CREUTZFELDT-JAKOB DISEASE R. G. WILL 1984

THE EPIDEMIOLOGY OF CREUTZFELDT-JAKOB DISEASE R. G. WILL

1984

snip...


THE BAXTER STUDY...SEE MORE HERE ;



Saturday, May 30, 2015

PRION 2015 ORAL AND POSTER CONGRESSIONAL ABSTRACTS


Wednesday, December 11, 2013

*** Detection of Infectivity in Blood of Persons with Variant and Sporadic Creutzfeldt-Jakob Disease ***


THE BAXTER STUDY...SEE MORE HERE ;


Thursday, November 12, 2015

Evaluation of the protection of primates transfused with variant Creutzfeldt-Jakob disease–infected blood products filtered with prion removal devices: a 5-year update


UK Iatrogenic Creutzfeldt–Jakob disease: investigating human prion transmission across genotypic barriers using human tissue-based and molecular approaches

Authors

Authors and affiliations

Diane L. Ritchie Marcelo A. Barria Alexander H. Peden Helen M. Yull James Kirkpatrick Peter Adlard James W. Ironside Mark W. Head Email author Diane L. Ritchie1 Marcelo A. Barria1 Alexander H. Peden1 Helen M. Yull1 James Kirkpatrick1 Peter Adlard2 James W. Ironside1 Mark W. Head13 Email author View author's OrcID profile

1.National CJD Research & Surveillance Unit, Centre for Clinical Brain Sciences, Deanery of Clinical SciencesThe University of Edinburgh Edinburgh UK

2.University College London Institute of Child HealthLondonUK

3.National CJD Research & Surveillance UnitUniversity of EdinburghEdinburghUK Open AccessOriginal Paper

First Online: 03 November 2016

DOI: 10.1007/s00401-016-1638-x Cite this article as: Ritchie, D.L., Barria, M.A., Peden, A.H. et al. Acta Neuropathol (2016). doi:10.1007/s00401-016-1638-x 40 Downloads 

Abstract

Creutzfeldt–Jakob disease (CJD) is the prototypic human prion disease that occurs most commonly in sporadic and genetic forms, but it is also transmissible and can be acquired through medical procedures, resulting in iatrogenic CJD (iCJD). The largest numbers of iCJD cases that have occurred worldwide have resulted from contaminated cadaveric pituitary-derived human growth hormone (hGH) and its use to treat primary and secondary growth hormone deficiency. We report a comprehensive, tissue-based and molecular genetic analysis of the largest series of UK hGH-iCJD cases reported to date, including in vitro kinetic molecular modelling of genotypic factors influencing prion transmission. The results show the interplay of prion strain and host genotype in governing the molecular, pathological and temporal characteristics of the UK hGH-iCJD epidemic and provide insights into the adaptive mechanisms involved when prions cross genotypic barriers. We conclude that all of the available evidence is consistent with the hypothesis that the UK hGH-iCJD epidemic resulted from transmission of the V2 human prion strain, which is associated with the second most common form of sporadic CJD.

Keywords

Creutzfeldt–Jakob disease Prion Iatrogenic Growth hormone Disease phenotype Agent strain

D. L. Ritchie and M. A. Barria contributed equally to this work.

Electronic supplementary material

The online version of this article (doi:10.1007/s00401-016-1638-x) contains supplementary material, which is available to authorized users.

SNIP...

Implications for person-to-person transmission

The RT-QuIC and PMCA comparisons performed here did not support the hypothesis that human-to-human transmission of CJD results in acquired replicative efficiency [36]. Indeed, the RT-QuIC assay showed reduced rather than enhanced seeding activity in hGH-iCJD compared to the matched subtypes of sCJD suggesting that hGH-iCJD is not markedly more of a public health concern than its presumed source, sCJD. However, CJD surveillance systems in countries where contaminated batches of growth hormone were used should remain vigilant for further cases of hGH-iCJD. Some of these cases may be identifiable by the presence of kuru plaques and the presence of PrPres type i. However, others cases may appear closely similar to the most common form of sCJD (MM1), and the only indication of an iatrogenic aetiology may be in their medical history. The overriding message from the UK experience with hGH-iCJD and perhaps human prion diseases, more generally, is that poorly assessed risks can continue to have ramifications for patients years to decades after the risk source is itself recognised and removed. This point is underscored by a further case of hGH-iCJD being identified during the writing of this report in 2016, some 30 years after treatment with pituitary-derived hGH was abandoned in the UK.

snip...see full text ;


Wednesday, December 11, 2013

*** Detection of Infectivity in Blood of Persons with Variant and Sporadic Creutzfeldt-Jakob Disease ***


-----Original Message----- 

From: Terry Singeltary <flounder9@verizon.net

To: bse-l <bse-l@lists.aegee.org

Cc: cjd-l <cjd-l@lists.aegee.org>; cjdvoice <cjdvoice@yahoogroups.com>; bloodcjd <bloodcjd@yahoogroups.com

Sent: Thu, Apr 27, 2017 11:11 am 

Subject: Creutzfeldt-Jakob disease lookback study: 21 years of surveillance for transfusion transmission risk

Subject: Creutzfeldt-Jakob disease lookback study: 21 years of surveillance for transfusion transmission risk

Creutzfeldt-Jakob disease lookback study: 21 years of surveillance for transfusion transmission risk 

Authors Lauren A. Crowder, Lawrence B. Schonberger, Roger Y. Dodd, Whitney R. Steele First published: 25 April 2017Full publication history DOI: 10.1111/trf.14145 View/save citation Cited by (CrossRef): 0 articles Check for updates Citation tools Funding Information 

The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention. 

This work has been funded by Grant 2 U01 CK000360-03 from the US Centers for Disease Control and Prevention. 

Abstract

BACKGROUND

Transfusion transmission of human prion diseases has been observed for variant Creutzfeldt-Jakob disease (vCJD), but not for the classic forms of prion disease (CJD: sporadic, genetic, and iatrogenic). Although the presence of prions or misfolded prion proteins in blood has been documented in some patients with the most common form of CJD, sporadic CJD, no transfusion-transmitted cases of CJD have been recognized. Since 1995, the American Red Cross has conducted a lookback study of the recipients of blood products from donors who develop CJD to assess the risk of blood-borne CJD transmission in the United States. 

STUDY DESIGN AND METHODS

Blood donors subsequently diagnosed with confirmed or probable CJD were enrolled and the consignees were asked to identify the recipients of their blood products. These donors' transfusion recipients are traced annually with the National Death Index to see if they subsequently die of CJD. 

RESULTS

To date, 65 CJD donors have been enrolled along with 826 of their blood recipients. These recipients have contributed 3934 person-years of follow-up and no transfusion-transmitted cases of CJD have been recognized. 

CONCLUSION

From this study, as well as other epidemiologic studies, there is no evidence of CJD transfusion transmission; this risk remains theoretical. 


with the USA CJD TSE Prion surveillance efforts to date, the efforts of trace back there from, the fact now that sporadic cjd has now been linked to typical and atypical BSE, typical and atypical Scrapie, and now scientist sounding the alarm of a threat of zoonosis from Chronic Wasting Disease CWD TSE Prion of cervid, the recent oral transmission of CWD to Pigs, this study is extremely flawed in my opinion, words on paper. sporadic CJD is not a single entity, but a name for many strains of CJD TSE Prion, that does not match the infamous nvCJD strain, that they have no clue as to what the routes and source of these CJDs strains are. ...kind regards, terry 

SUNDAY, MARCH 09, 2014

A Creutzfeldt-Jakob Disease (CJD) Lookback Study: Assessing the Risk of Blood Borne Transmission of Classic Forms of Creutzfeldt-Jakob Disease


Thursday, April 02, 2009

MORE Blood products collected from a donor considered to be at increased risk for vCJD, were distributed USA APRIL 1, 2009


There is a new sheriff in town, and I hope he plans on 'sound science', to take the reins, instead of the previous 8 years of 'junk science'.

The UKBSEnvCJD only theory is wrong, and to continue with this policy, will only enhance the spread of human and animal TSE Globally. ...

Thank You,

With Kindest Regards,

I am sincerely,

Terry S. Singeltary Sr. P.O. Box Bacliff, Texas USA 77518

SATURDAY, DECEMBER 08, 2007 

Transfusion Transmission of Human Prion Diseases


Confucius is confused again?

''The rare genetic forms of CJD (e.g., fCJD, GSS, FFI) share pathophysiological features with sCJD, and the transmission risk by blood components remains theoretical. Consequently, we recommend that establishments may stop asking prospective donors about having blood relatives with CJD.''

YET, vpspr, sporadic FFI, sporadic GSS, or the pending cases that can't be identified, are all now listed as sporadic CJD.

WHAT IF, sGSS, sFFI, are of an iatrogenic event from iatrogenic donor being from GSS or FFI?

what if vpspr is another strain of a different sporadic CJD, or familial? see;

7Includes 21 (21 from 2019) cases with type determination pending in which the diagnosis of vCJD has been excluded. 

8The sporadic cases include 3831 cases of sporadic Creutzfeldt-Jakob disease (sCJD), 67 cases of Variably Protease-Sensitive Prionopathy (VPSPr) and 35 cases of sporadic Fatal Insomnia (sFI). 

9Total does not include 264 Familial cases diagnosed by blood test only.


under new proposed guidelines ''we recommend that establishments may stop asking prospective donors about having blood relatives with CJD'' (of which i strongly oppose due to the fact sporadic cjd is not a single entity or a spontaneous event, never which have been proven), but under these guidelines, you will miss the vpspr, sgss, and sffi, because they are under sporadic cjd terminology, would you not?

The occurrence of the disease in a patient who had contact with cases of familial C.J.D., but was not genetically related, has been described in Chile (Galvez et al., 1980) and in France (Brown et al., 1979b). In Chile the patient was related by marriage, but with no consanguinity, and had social contact with subsequently affected family members for 13 years before developing the disease. The contact case in France also married into a family in which C.J.D. was prevalent and had close contact with an affected member. In neither instance did the spouse of the non-familial case have the disease. The case described in this report was similarly related to affected family members and social contact had occurred for 20 years prior to developing C.J.D. If contact transmission had occurred, the minimum transmission period would be 11 years. Contact between sporadic cases has not been described and it is remarkable that possible contact transmissions have all been with familial cases. No method of transmission by casual social contact has been suggested.

WHAT IF?

***The occurrence of contact cases raises the possibility that transmission in families may be effected by an unusually virulent strain of the agent.

snip...see full text here;



Sporadic Creutzfeldt-Jakob Disease in a Woman Married Into a Gerstmann-Sträussler-Scheinker Family: An Investigation of Prions Transmission via Microchimerism 

Aušrinė Areškevičiūtė, MSc, Linea Cecilie Melchior, PhD, Helle Broholm, MD, Lars-Henrik Krarup, MD, PhD, Suzanne Granhøj Lindquist, MD, PhD, Peter Johansen, PhD, Neil McKenzie, PhD, Alison Green, PhD, Jørgen Erik Nielsen, MD, PhD, Henning Laursen, Dr.Med, Eva Løbner Lund, MD, PhD Journal of Neuropathology & Experimental Neurology, Volume 77, Issue 8, August 2018, Pages 673–684, https://doi.org/10.1093/jnen/nly043 Published: 07 June 2018

DISCUSSION

This is the first report of presumed sporadic CJD occurring in a person who married into a GSS family. The estimated prevalence of GSS is in the range of 2–5 per 100 million people worldwide, and the annual mortality rate for sCJD in Denmark is 1.46 per 1 million people (31). The population of Denmark consists of 5 740 185 individuals, and there are 2 registered GSS cases that belong to the same family. The Danish GSS family is only the thirty-fourth known GSS family in the world (32). One could assume that the risk for a Danish man with GSS to have a wife or a mother who would develop CJD in her seventies is as high as for any other man. On the basis of the mortality rate for sCJD, and assuming that the incidence of sCJD is the same among married and unmarried people, we could state that 1 man out of 684 932 men has a risk of marrying a woman who would develop CJD. However, in this case, the man a priori had GSS, which means that it would take 1 man out of 684 932 men with GSS for such a pairing to occur. Considering the worldwide rarity of GSS cases, the likelihood for co-occurrence of GSS and sCJD in one family is hence very low and warrants an investigation for the possible transmission of prions routes.


Volume 25, Number 1—January 2019

Research

Variable Protease-Sensitive Prionopathy Transmission to Bank Vol

Romolo Nonno1, Silvio Notari1, Michele Angelo Di Bari, Ignazio Cali, Laura Pirisinu, Claudia d’Agostino, Laura Cracco, Diane Kofskey, Ilaria Vanni, Jody Lavrich, Piero Parchi, Umberto Agrimi, and Pierluigi GambettiComments to Author 

Author affiliations: Istituto Superiore di Sanità, Rome, Italy (R. Nonno, M.A. Di Bari, L. Pirisinu, C. d’Agostino, I. Vanni, U. Agrimi); Case Western Reserve University, Cleveland, Ohio, USA (S. Notari, I. Cali, L. Cracco, D. Kofskey, J. Lavrich, P. Gambetti); University of Bologna, Bologna, Italy (P. Parchi); Istituto delle Scienze Neurologiche di Bologna, Bologna (P. Parchi)

***> However, the VPSPr prion shares the multiplicity of the resPrPD electrophoretic bands with prions from a subset of inherited prion diseases referred to as Gerstmann-Sträussler-Scheinker disease (GSS), prompting the suggestion that VPSPr is the sporadic form of GSS (7,10). Furthermore, the presence of small amounts of sCJD-like 3-band resPrPD has also been signaled in VPSPr (6,11,12).


FRIDAY, JANUARY 10, 2014

vpspr, sgss, sffi, TSE, an iatrogenic by-product of gss, ffi, familial type prion disease, what it ???

Greetings Friends, Neighbors, and Colleagues,

vpspr, sgss, sffi, TSE, an iatrogenic by-product of gss, ffi, familial type prion disease, what it ???

Confucius is confused again.

I was just sitting and thinking about why there is no genetic link to some of these TSE prion sGSS, sFFi, and it’s really been working on my brain, and then it hit me today.
what if, vpspr, sgss, sffi, TSE prion disease, was a by-product from iatrogenic gss, ffi, familial type prion disease ???
it could explain the cases of no genetic link to the gss, ffi, familial type prion disease, to the family.
sporadic and familial is a red herring, in my opinion, and underestimation is spot on, due to the crude prehistoric diagnostic procedures and criteria and definition of a prion disease.
I say again, what if, iatrogenic, what if, with all these neurological disorders, with a common denominator that is increasingly showing up in the picture, called the prion.
I urge all scientist to come together here, with this as the utmost of importance about all these neurological disease that are increasingly showing up as a prion mechanism, to put on the front burners, the IATROGENIC aspect and the potential of transmission there from, with diseases/disease??? in question.
by definition, could they be a Transmissible Spongiform Encephalopathy TSE prion type disease, and if so, what are the iatrogenic chances of transmission?
this is very important, and should be at the forefront of research, and if proven, could be a monumental breakthrough in science and battle against the spreading of these disease/diseases.

sporadic CJD, along with new TSE prion disease in humans, of which the young are dying, of which long duration of illness from onset of symptoms to death have been documented, only to have a new name added to the pot of prion disease i.e. sporadic GSS, sporadic FFI, and or VPSPR. I only ponder how a familial type disease could be sporadic with no genetic link to any family member? when the USA is the only documented Country in the world to have documented two different cases of atypical H-type BSE, with one case being called atypical H-G BSE with the G meaning Genetic, with new science now showing that indeed atypical H-type BSE is very possible transmitted to cattle via oral transmission (Prion2014). sporadic CJD and VPSPR have been rising in Canada, USA, and the UK, with the same old excuse, better surveillance. You can only use that excuse for so many years, for so many decades, until one must conclude that CJD TSE prion cases are rising. a 48% incease in CJD in Canada is not just a blip or a reason of better surveillance, it is a mathematical rise in numbers. More and more we are seeing more humans exposed in various circumstance in the Hospital, Medical, Surgical arenas to the TSE Prion disease, and at the same time in North America, more and more humans are becoming exposed to the TSE prion disease via consumption of the TSE prion via deer and elk, cattle, sheep and goats, and for those that are exposed via or consumption, go on to further expose many others via the iatrogenic modes of transmission of the TSE prion disease i.e. friendly fire. I pondered this mode of transmission via the victims of sporadic FFI, sporadic GSS, could this be a iatrogenic event from someone sub-clinical with sFFI or sGSS ? what if?
Alzheimer's disease

let's not forget the elephant in the room. curing Alzheimer's would be a great and wonderful thing, but for starters, why not start with the obvious, lets prove the cause or causes, and then start to stop that. think iatrogenic, friendly fire, or the pass it forward mode of transmission. think medical, surgical, dental, tissue, blood, related transmission. think transmissible spongiform encephalopathy aka tse prion disease aka mad cow type disease... 

Commentary: Evidence for human transmission of amyloid-β pathology and cerebral amyloid angiopathy





Self-Propagative Replication of Ab Oligomers Suggests Potential Transmissibility in Alzheimer Disease 

*** Singeltary comment PLoS *** 

Alzheimer’s disease and Transmissible Spongiform Encephalopathy prion disease, Iatrogenic, what if ? 

Posted by flounder on 05 Nov 2014 at 21:27 GMT 


IN CONFIDENCE

5 NOVEMBER 1992

TRANSMISSION OF ALZHEIMER TYPE PLAQUES TO PRIMATES

[9. Whilst this matter is not at the moment directly concerned with the iatrogenic CJD cases from hgH, there remains a possibility of litigation here, and this presents an added complication. 

There are also results to be made available shortly 

(1) concerning a farmer with CJD who had BSE animals, 

(2) on the possible transmissibility of Alzheimer’s and 

(3) a CMO letter on prevention of iatrogenic CJD transmission in neurosurgery, all of which will serve to increase media interest.]




THURSDAY, FEBRUARY 15, 2018 

Iatrogenic Creutzfeldt-Jakob disease with Amyloid-β pathology: an international study

http://creutzfeldt-jakob-disease.blogspot.com/2018/02/iatrogenic-creutzfeldt-jakob-disease.html

2.3.2. New evidence on the zoonotic potential of atypical BSE and atypical scrapie prion strains

PLEASE NOTE;

2.3.2. New evidence on the zoonotic potential of atypical BSE and atypical scrapie prion strains

Olivier Andreoletti, INRA Research Director, Institut National de la Recherche Agronomique (INRA) – École Nationale Vétérinaire de Toulouse (ENVT), invited speaker, presented the results of two recently published scientific articles of interest, of which he is co-author: ‘Radical Change in Zoonotic Abilities of Atypical BSE Prion Strains as Evidenced by Crossing of Sheep Species Barrier in Transgenic Mice’ (MarinMoreno et al., 2020) and ‘The emergence of classical BSE from atypical/Nor98 scrapie’ (Huor et al., 2019).

In the first experimental study, H-type and L-type BSE were inoculated into transgenic mice expressing all three genotypes of the human PRNP at codon 129 and into adapted into ARQ and VRQ transgenic sheep mice. The results showed the alterations of the capacities to cross the human barrier species (mouse model) and emergence of sporadic CJD agents in Hu PrP expressing mice: type 2 sCJD in homozygous TgVal129 VRQ-passaged L-BSE, and type 1 sCJD in homozygous TgVal 129 and TgMet129 VRQ-passaged H-BSE.


TSE PRION ZOONOSIS ZOONOTIC POTENTIAL

O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations 
Emmanuel Comoy, Jacqueline Mikol, Valerie Durand, Sophie Luccantoni, Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys Atomic Energy Commission; Fontenay-aux-Roses, France 

Prion diseases (PD) are the unique neurodegenerative proteinopathies reputed to be transmissible under field conditions since decades. The transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that an animal PD might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, PD, like the other proteinopathies, are reputed to occur spontaneously (atpical animal prion strains, sporadic CJD summing 80% of human prion cases). 

Non-human primate models provided the first evidences supporting the transmissibiity of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health (Chen, 2014), according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the zoonotic potential of other animal PD from bovine, ovine and cervid origins even after very long silent incubation periods. 

*** We recently observed the direct transmission of a natural classical scrapie isolate to macaque after a 10-year silent incubation period, 

***with features similar to some reported for human cases of sporadic CJD, albeit requiring fourfold long incubation than BSE. Scrapie, as recently evoked in humanized mice (Cassard, 2014), 

***is the third potentially zoonotic PD (with BSE and L-type BSE), 

***thus questioning the origin of human sporadic cases. 

We will present an updated panorama of our different transmission studies and discuss the implications of such extended incubation periods on risk assessment of animal PD for human health. 

=============== 

***thus questioning the origin of human sporadic cases*** 

=============== 

***our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals. 

============== 

https://prion2015.files.wordpress.com/2015/05/prion2015abstracts.pdf 

***Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with efficiency comparable to that of cattle BSE. While the efficiency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice. 

***Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion. 

***These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions. 

http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20 

PRION 2016 TOKYO

Saturday, April 23, 2016

SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016

Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online

Taylor & Francis

Prion 2016 Animal Prion Disease Workshop Abstracts

WS-01: Prion diseases in animals and zoonotic potential

Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion. 

These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions. 

http://www.tandfonline.com/doi/abs/10.1080/19336896.2016.1163048?journalCode=kprn20

Title: Transmission of scrapie prions to primate after an extended silent incubation period) 

*** In complement to the recent demonstration that humanized mice are susceptible to scrapie, we report here the first observation of direct transmission of a natural classical scrapie isolate to a macaque after a 10-year incubation period. Neuropathologic examination revealed all of the features of a prion disease: spongiform change, neuronal loss, and accumulation of PrPres throughout the CNS. 

*** This observation strengthens the questioning of the harmlessness of scrapie to humans, at a time when protective measures for human and animal health are being dismantled and reduced as c-BSE is considered controlled and being eradicated. 

*** Our results underscore the importance of precautionary and protective measures and the necessity for long-term experimental transmission studies to assess the zoonotic potential of other animal prion strains. 

http://www.ars.usda.gov/research/publications/publications.htm?SEQ_NO_115=313160

1: J Infect Dis 1980 Aug;142(2):205-8

Oral transmission of kuru, Creutzfeldt-Jakob disease, and scrapie to nonhuman primates.

Gibbs CJ Jr, Amyx HL, Bacote A, Masters CL, Gajdusek DC.

Kuru and Creutzfeldt-Jakob disease of humans and scrapie disease of sheep and goats were transmitted to squirrel monkeys (Saimiri sciureus) that were exposed to the infectious agents only by their nonforced consumption of known infectious tissues. The asymptomatic incubation period in the one monkey exposed to the virus of kuru was 36 months; that in the two monkeys exposed to the virus of Creutzfeldt-Jakob disease was 23 and 27 months, respectively; and that in the two monkeys exposed to the virus of scrapie was 25 and 32 months, respectively. Careful physical examination of the buccal cavities of all of the monkeys failed to reveal signs or oral lesions. One additional monkey similarly exposed to kuru has remained asymptomatic during the 39 months that it has been under observation.

snip...

The successful transmission of kuru, Creutzfeldt-Jakob disease, and scrapie by natural feeding to squirrel monkeys that we have reported provides further grounds for concern that scrapie-infected meat may occasionally give rise in humans to Creutzfeldt-Jakob disease.

PMID: 6997404


Recently the question has again been brought up as to whether scrapie is transmissible to man. This has followed reports that the disease has been transmitted to primates. One particularly lurid speculation (Gajdusek 1977) conjectures that the agents of scrapie, kuru, Creutzfeldt-Jakob disease and transmissible encephalopathy of mink are varieties of a single "virus". The U.S. Department of Agriculture concluded that it could "no longer justify or permit scrapie-blood line and scrapie-exposed sheep and goats to be processed for human or animal food at slaughter or rendering plants" (ARC 84/77)" The problem is emphasised by the finding that some strains of scrapie produce lesions identical to the once which characterise the human dementias"

Whether true or not. the hypothesis that these agents might be transmissible to man raises two considerations. First, the safety of laboratory personnel requires prompt attention. Second, action such as the "scorched meat" policy of USDA makes the solution of the acrapie problem urgent if the sheep industry is not to suffer grievously.

snip...

76/10.12/4.6


Nature. 1972 Mar 10;236(5341):73-4.

Transmission of scrapie to the cynomolgus monkey (Macaca fascicularis).

Gibbs CJ Jr, Gajdusek DC.

Nature 236, 73 - 74 (10 March 1972); doi:10.1038/236073a0

Transmission of Scrapie to the Cynomolgus Monkey (Macaca fascicularis)

C. J. GIBBS jun. & D. C. GAJDUSEK

National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, Maryland

SCRAPIE has been transmitted to the cynomolgus, or crab-eating, monkey (Macaca fascicularis) with an incubation period of more than 5 yr from the time of intracerebral inoculation of scrapie-infected mouse brain. The animal developed a chronic central nervous system degeneration, with ataxia, tremor and myoclonus with associated severe scrapie-like pathology of intensive astroglial hypertrophy and proliferation, neuronal vacuolation and status spongiosus of grey matter. The strain of scrapie virus used was the eighth passage in Swiss mice (NIH) of a Compton strain of scrapie obtained as ninth intracerebral passage of the agent in goat brain, from Dr R. L. Chandler (ARC, Compton, Berkshire).



Wednesday, February 16, 2011

IN CONFIDENCE

SCRAPIE TRANSMISSION TO CHIMPANZEES

IN CONFIDENCE


> However, to date, no CWD infections have been reported in people.
key word here is ‘reported’. science has shown that CWD in humans will look like sporadic CJD. SO, how can one assume that CWD has not already transmitted to humans? they can’t, and it’s as simple as that. from all recorded science to date, CWD has already transmitted to humans, and it’s being misdiagnosed as sporadic CJD. …terry
*** LOOKING FOR CWD IN HUMANS AS nvCJD or as an ATYPICAL CJD, LOOKING IN ALL THE WRONG PLACES $$$ ***
*** These results would seem to suggest that CWD does indeed have zoonotic potential, at least as judged by the compatibility of CWD prions and their human PrPC target. Furthermore, extrapolation from this simple in vitro assay suggests that if zoonotic CWD occurred, it would most likely effect those of the PRNP codon 129-MM genotype and that the PrPres type would be similar to that found in the most common subtype of sCJD (MM1).***
Chronic Wasting Disease CWD TSE Prion aka mad deer disease zoonosis
We hypothesize that:
(1) The classic CWD prion strain can infect humans at low levels in the brain and peripheral lymphoid tissues;
(2) The cervid-to-human transmission barrier is dependent on the cervid prion strain and influenced by the host (human) prion protein (PrP) primary sequence;
(3) Reliable essays can be established to detect CWD infection in humans; and
(4) CWD transmission to humans has already occurred. We will test these hypotheses in 4 Aims using transgenic (Tg) mouse models and complementary in vitro approaches.
ZOONOTIC CHRONIC WASTING DISEASE CWD TSE PRION UPDATE
Prion 2017 Conference
First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques: a work in progress Stefanie Czub1, Walter Schulz-Schaeffer2, Christiane Stahl-Hennig3, Michael Beekes4, Hermann Schaetzl5 and Dirk Motzkus6 1 
University of Calgary Faculty of Veterinary Medicine/Canadian Food Inspection Agency; 2Universitatsklinikum des Saarlandes und Medizinische Fakultat der Universitat des Saarlandes; 3 Deutsches Primaten Zentrum/Goettingen; 4 Robert-Koch-Institut Berlin; 5 University of Calgary Faculty of Veterinary Medicine; 6 presently: Boehringer Ingelheim Veterinary Research Center; previously: Deutsches Primaten Zentrum/Goettingen 
This is a progress report of a project which started in 2009. 21 cynomolgus macaques were challenged with characterized CWD material from white-tailed deer (WTD) or elk by intracerebral (ic), oral, and skin exposure routes. Additional blood transfusion experiments are supposed to assess the CWD contamination risk of human blood product. Challenge materials originated from symptomatic cervids for ic, skin scarification and partially per oral routes (WTD brain). Challenge material for feeding of muscle derived from preclinical WTD and from preclinical macaques for blood transfusion experiments. We have confirmed that the CWD challenge material contained at least two different CWD agents (brain material) as well as CWD prions in muscle-associated nerves. 
Here we present first data on a group of animals either challenged ic with steel wires or per orally and sacrificed with incubation times ranging from 4.5 to 6.9 years at postmortem. Three animals displayed signs of mild clinical disease, including anxiety, apathy, ataxia and/or tremor. In four animals wasting was observed, two of those had confirmed diabetes. All animals have variable signs of prion neuropathology in spinal cords and brains and by supersensitive IHC, reaction was detected in spinal cord segments of all animals. Protein misfolding cyclic amplification (PMCA), real-time quaking-induced conversion (RT-QuiC) and PET-blot assays to further substantiate these findings are on the way, as well as bioassays in bank voles and transgenic mice. 
At present, a total of 10 animals are sacrificed and read-outs are ongoing. Preclinical incubation of the remaining macaques covers a range from 6.4 to 7.10 years. Based on the species barrier and an incubation time of > 5 years for BSE in macaques and about 10 years for scrapie in macaques, we expected an onset of clinical disease beyond 6 years post inoculation. 
PRION 2017 DECIPHERING NEURODEGENERATIVE DISORDERS 
PRION 2018 CONFERENCE
Oral transmission of CWD into Cynomolgus macaques: signs of atypical disease, prion conversion and infectivity in macaques and bio-assayed transgenic mice
Hermann M. Schatzl, Samia Hannaoui, Yo-Ching Cheng, Sabine Gilch (Calgary Prion Research Unit, University of Calgary, Calgary, Canada) Michael Beekes (RKI Berlin), Walter Schulz-Schaeffer (University of Homburg/Saar, Germany), Christiane Stahl-Hennig (German Primate Center) & Stefanie Czub (CFIA Lethbridge).
To date, BSE is the only example of interspecies transmission of an animal prion disease into humans. The potential zoonotic transmission of CWD is an alarming issue and was addressed by many groups using a variety of in vitro and in vivo experimental systems. Evidence from these studies indicated a substantial, if not absolute, species barrier, aligning with the absence of epidemiological evidence suggesting transmission into humans. Studies in non-human primates were not conclusive so far, with oral transmission into new-world monkeys and no transmission into old-world monkeys. Our consortium has challenged 18 Cynomolgus macaques with characterized CWD material, focusing on oral transmission with muscle tissue. Some macaques have orally received a total of 5 kg of muscle material over a period of 2 years.
After 5-7 years of incubation time some animals showed clinical symptoms indicative of prion disease, and prion neuropathology and PrPSc deposition were detected in spinal cord and brain of some euthanized animals. PrPSc in immunoblot was weakly detected in some spinal cord materials and various tissues tested positive in RT-QuIC, including lymph node and spleen homogenates. To prove prion infectivity in the macaque tissues, we have intracerebrally inoculated 2 lines of transgenic mice, expressing either elk or human PrP. At least 3 TgElk mice, receiving tissues from 2 different macaques, showed clinical signs of a progressive prion disease and brains were positive in immunoblot and RT-QuIC. Tissues (brain, spinal cord and spleen) from these and pre-clinical mice are currently tested using various read-outs and by second passage in mice. Transgenic mice expressing human PrP were so far negative for clear clinical prion disease (some mice >300 days p.i.). In parallel, the same macaque materials are inoculated into bank voles.
Taken together, there is strong evidence of transmissibility of CWD orally into macaques and from macaque tissues into transgenic mouse models, although with an incomplete attack rate.
The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology.
Our ongoing studies will show whether the transmission of CWD into macaques and passage in transgenic mice represents a form of non-adaptive prion amplification, and whether macaque-adapted prions have the potential to infect mice expressing human PrP.
The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD..
***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD. <***
Prion Conference 2018
READING OVER THE PRION 2018 ABSTRACT BOOK, LOOKS LIKE THEY FOUND THAT from this study ;
P190 Human prion disease mortality rates by occurrence of chronic wasting disease in freeranging cervids, United States
Abrams JY (1), Maddox RA (1), Schonberger LB (1), Person MK (1), Appleby BS (2), Belay ED (1) (1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA..
SEEMS THAT THEY FOUND Highly endemic states had a higher rate of prion disease mortality compared to non-CWD
states.
AND ANOTHER STUDY;
P172 Peripheral Neuropathy in Patients with Prion Disease
Wang H(1), Cohen M(1), Appleby BS(1,2) (1) University Hospitals Cleveland Medical Center, Cleveland, Ohio (2) National Prion Disease Pathology Surveillance Center, Cleveland, Ohio..
IN THIS STUDY, THERE WERE autopsy-proven prion cases from the National Prion Disease Pathology Surveillance Center that were diagnosed between September 2016 to March 2017,
AND
included 104 patients. SEEMS THEY FOUND THAT The most common sCJD subtype was MV1-2 (30%), followed by MM1-2 (20%),
AND
THAT The Majority of cases were male (60%), AND half of them had exposure to wild game.
snip…
see more on Prion 2017 Macaque study from Prion 2017 Conference and other updated science on cwd tse prion zoonosis below…terry
Prion 2018 Conference
8. Even though human TSE‐exposure risk through consumption of game from European cervids can be assumed to be minor, if at all existing, no final conclusion can be drawn due to the overall lack of scientific data. In particular the US data do not clearly exclude the possibility of human (sporadic or familial) TSE development due to consumption of venison. The Working Group thus recognizes a potential risk to consumers if a TSE would be present in European cervids. It might be prudent considering appropriate measures to reduce such a risk, e.g. excluding tissues such as CNS and lymphoid tissues from the human food chain, which would greatly reduce any potential risk for consumers. However, it is stressed that currently, no data regarding a risk of TSE infections from cervid products are available.
International Conference on Emerging Diseases, Outbreaks & Case Studies & 16th Annual Meeting on Influenza March 28-29, 2018 | Orlando, USA
Qingzhong Kong
Case Western Reserve University School of Medicine, USA
Zoonotic potential of chronic wasting disease prions from cervids
Chronic wasting disease (CWD) is the prion disease in cervids (mule deer, white-tailed deer, American elk, moose, and reindeer). It has become an epidemic in North America, and it has been detected in the Europe (Norway) since 2016. The widespread CWD and popular hunting and consumption of cervid meat and other products raise serious public health concerns, but questions remain on human susceptibility to CWD prions, especially on the potential difference in zoonotic potential among the various CWD prion strains. We have been working to address this critical question for well over a decade. We used CWD samples from various cervid species to inoculate transgenic mice expressing human or elk prion protein (PrP). We found infectious prions in the spleen or brain in a small fraction of CWD-inoculated transgenic mice expressing human PrP, indicating that humans are not completely resistant to CWD prions; this finding has significant ramifications on the public health impact of CWD prions. The influence of cervid PrP polymorphisms, the prion strain dependence of CWD-to-human transmission barrier, and the characterization of experimental human CWD prions will be discussed.
Speaker Biography Qingzhong Kong has completed his PhD from the University of Massachusetts at Amherst and Post-doctoral studies at Yale University. He is currently an Associate Professor of Pathology, Neurology and Regenerative Medicine. He has published over 50 original research papers in reputable journals (including Science Translational Medicine, JCI, PNAS and Cell Reports) and has been serving as an Editorial Board Member on seven scientific journals. He has multiple research interests, including public health risks of animal prions (CWD of cervids and atypical BSE of cattle), animal modeling of human prion diseases, mechanisms of prion replication and pathogenesis, etiology of sporadic Creutzfeldt-Jacob disease (CJD) in humans, normal cellular PrP in the biology and pathology of multiple brain and peripheral diseases, proteins responsible for the α-cleavage of cellular PrP, as well as gene therapy and DNA vaccination.
Monday, September 14, 2020 

Assessing the aggregated probability of entry of a novel prion disease agent into the United Kingdom


TUESDAY, DECEMBER 01, 2020 

Sporadic Creutzfeldt Jakob Disease sCJD and Human TSE Prion Annual Report December 14, 2020 


SATURDAY, FEBRUARY 20, 2021 
Abnormal prion protein deposits with high seeding activities in the skeletal muscle, femoral nerve, and scalp of an autopsied case of sporadic Creutzfeldt–Jakob disease
SUNDAY, AUGUST 09, 2009

CJD...Straight talk with...James Ironside...and...Terry Singeltary... 2009


TUESDAY, AUGUST 18, 2009

BSE-The Untold Story - joe gibbs and singeltary 1999 - 2009


Diagnosis and Reporting of Creutzfeldt-Jakob Disease 

Singeltary, Sr et al. JAMA.2001; 285: 733-734. Vol. 285 No. 6, February 14, 2001 JAMA Diagnosis and Reporting of Creutzfeldt-Jakob Disease To the Editor: 

In their Research Letter, Dr Gibbons and colleagues1 reported that the annual US death rate due to Creutzfeldt-Jakob disease (CJD) has been stable since 1985. These estimates, however, are based only on reported cases, and do not include misdiagnosed or preclinical cases. It seems to me that misdiagnosis alone would drastically change these figures. An unknown number of persons with a diagnosis of Alzheimer disease in fact may have CJD, although only a small number of these patients receive the postmortem examination necessary to make this diagnosis. Furthermore, only a few states have made CJD reportable. Human and animal transmissible spongiform encephalopathies should be reportable nationwide and internationally.. 

Terry S. Singeltary, Sr Bacliff, Tex 

1. Gibbons RV, Holman RC, Belay ED, Schonberger LB. Creutzfeldt-Jakob disease in the United States: 1979-1998. JAMA. 2000;284:2322-2323. 


WEDNESDAY, MARCH 24, 2021 

USDA Animal and Plant Health Inspection Service 2020 IMPACT REPORT BSE TSE Prion Testing and Surveillance MIA


Terry S. Singeltary Sr.