PRION 2017 CONFERENCE ABSTRACT First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques: a work in progress
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
TUESDAY, JUNE 13, 2017
PRION 2017 CONFERENCE ABSTRACT First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques: a work in progress
10:30 First evidence of intracranial and peroral transmission of Chronic Wasting Disease (CWD) into Cynomolgus macaques: a work in progress
Dr Stefanie Czub University of Calgary Faculty of Veterinary Medicine/Canadian Food Inspection Agency Canada
http://prion2017.org/programme/
Notice to Members Regarding Chronic Wasting Disease (CWD)
To: MNA Members
From: Métis Nation of Alberta
Date: Wednesday, May 31, 2017
Métis Nation of Alberta (MNA) was made aware of a recent Canadian research study examining the transmission of Chronic Wasting Disease. The initial results of the study indicate that macaque monkeys (genetically similar to humans) can be infected with Chronic Wasting Disease (CWD) after eating deer that is infected with CWD. CWD is a prion disease, which are fatal, transmissible diseases characterized by abnormal proteins in the brain and nervous system. To date no research has shown that CWD can be passed on to humans, and no human cases of CWD have ever been identified. However, this new research indicates that it is a possibility. The Deputy Chief Medical Officer of Health has reached out to us to share with our Métis harvesters this important information.
For more information you can visit:
and
What the Alberta Government knows:
Necessary Precautions for Harvesters:
- Hunters and others who handle carcasses follow basic handling precautions (available here http://aep.alberta.ca/fish-wildlife/fishing-hunting-trapping/hunting-alberta/documents/CWDGuidelines-DeerCarcassTransportationHandling-Oct2009.pdf
- All deer, moose and elk harvested from CWD mandatory submission wildlife management units (WMUs) be tested for CWD; and
- A negative result (no CWD detected by the test) must be obtained before any part of an animal is eaten.
For more information, contact:
Amy Quintal
Métis Nation of Alberta
Métis Harvesting Liaison
Tel: (780) 455 – 2200
aquintal@metis.org
THIS IS AN UNOFFICIAL UPDATE OF THE ABOVE RESEARCH OF WHICH HAS NOT BEEN RELEASED YET, NO URL LINK...TSS
Chronic Wasting Disease: CFIA Research Summary
Embargoed until May 23, 2017
(OCR of a scanned original)
Research Findings
Chronic Wasting Disease (CWD) is a progressive, fatal disease of the nervous system of cervids including deer, elk, moose, and reindeer that is caused by abnormal proteins called prions. It is known as a transmissible spongiform encephalopathy (TSE). Other TSEs include scrapie in sheep, bovine spongiform encephalopathy (BSE) in cattle, and Creutzfeldt-Jakob disease (CJD) in humans.
A limited number of experimental studies have demonstrated that non-human primates, specifically squirrel monkeys, are susceptible to CWD prions. An ongoing research study has now shown that CWD can also be transmitted to macaques, which are genetically closer to humans.
The study led by Dr. Stefanie Czub, a scientist at the Canadian Food Inspection Agency (CFIA), and funded by the Alberta Prion Research institute has demonstrated that by orally administering material under experimental conditions from cervids (deer and elk) naturally infected with CWD, the disease can be transmitted to macaques.
in this project, which began in 2009, 18 macaques were exposed to CWD in a variety of ways: by injecting into the brain, through contact with skin, oral administration, and intravenously (into the bloodstream through veins). So far, results are available from 5 animals. At this point, two animals that were exposed to CWD by direct introduction into the brain, one that was administered infected brain material by oral administration and two that were given infected muscle by oral administration have become infected with CWD. The study is ongoing and testing continues in the remaining animals. The early results will be presented at PRlON 2017, the annual international conference on prion diseases, in Edinburgh, Scotland, May 23 to 26, 2017.
Potential impacts of the new finding
Since 2003 Canada has a policy that recommends that animals and materials known to be infected with prions be removed from the food chain and from health products. Although no direct evidence of CWD prion transmission to humans has ever been recorded, the policy advocates a precautionary approach to managing CWD and potential human exposure to prions. These initial findings do not change Health Canada’s Health Products and Food Branch (HPFB) position on food and health products. A precautionary approach is still recommended to manage the potential risks of exposure to prions through food and health products. Measures are in place at federal, provincial and territorial levels to reduce human exposure to products potentially contaminated by CWD by preventing known infected animals from entering the marketplace.
While Federal and P/T government’s animal disease control policies continue to divert known CWD-infected animals away from entering the food and feed supply, research and development of sensitive detection methods including live-animal sampling techniques remain crucial for ensuring an accurate diagnosis. In addition, consistent federal, provincial and territorial communications of appropriate precautionary measures for hunters and indigenous communities are required.
Next Steps
The CFlA will continue to collaborate with national and international partners to develop and validate new diagnostic techniques. The CFlA will also continue to offer confirmatory testing services and reference laboratory expertise to provincial and territorial partners on demand.
Currently, CFlA laboratories are leading or collaborating on several research projects to understand the potential for CWD to infect humans. These projects use non‐human primates, genetically modified mice, and cell-free amplification approaches. Given the present findings, CFiA encourages continued research into TSEs.
The results of this study reinforce the need to redesign the federal program to foster greater adoption of risk mitigation measures for farmed cervids. Federal and provincial government collaboration will continue as new program options are assessed.
The results of Dr. Czub’s research into CWD will be of interest to scientists, governments, industry and people who consume cervid products. After the presentation at PRION 2017, the research will follow the normal steps of completion, peer review and publication. The Government of Canada will monitor the response to this research and determine whether further review of the science is required. Other studies underway by other researchers may also become public as a result of the presentation of Dr. Czub’s research.
The Public Health Agency of Canada, Health Canada, CFlA and other Federal partners are working together to assess what policies or programs need further review as well as preparing other communications about the research and health policy and advice to Canadian. 2017/04/28
===end...tss===
seems if my primitive education does not fail me, intracranial means inside the skull, and peroral means by the mouth. seems the price of tse prion poker just keeps going up...terry
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES
Location: Virus and Prion Research
Title: Disease-associated prion protein detected in lymphoid tissues from pigs challenged with the agent of chronic wasting disease
Author item Moore, Sarah item Kunkle, Robert item Kondru, Naveen item Manne, Sireesha item Smith, Jodi item Kanthasamy, Anumantha item West Greenlee, M item Greenlee, Justin
Submitted to: Prion Publication Type: Abstract Only Publication Acceptance Date: 3/15/2017 Publication Date: N/A Citation: N/A Interpretive Summary:
Technical Abstract: Aims: Chronic wasting disease (CWD) is a naturally-occurring, fatal neurodegenerative disease of cervids. We previously demonstrated that disease-associated prion protein (PrPSc) can be detected in the brain and retina from pigs challenged intracranially or orally with the CWD agent. In that study, neurological signs consistent with prion disease were observed only in one pig: an intracranially challenged pig that was euthanized at 64 months post-challenge. The purpose of this study was to use an antigen-capture immunoassay (EIA) and real-time quaking-induced conversion (QuIC) to determine whether PrPSc is present in lymphoid tissues from pigs challenged with the CWD agent. Methods: At two months of age, crossbred pigs were challenged by the intracranial route (n=20), oral route (n=19), or were left unchallenged (n=9). At approximately 6 months of age, the time at which commercial pigs reach market weight, half of the pigs in each group were culled (<6 challenge="" groups="" month="" pigs="" remaining="" the="">6 month challenge groups) were allowed to incubate for up to 73 months post challenge (mpc). The retropharyngeal lymph node (RPLN) was screened for the presence of PrPSc by EIA and immunohistochemistry (IHC). The RPLN, palatine tonsil, and mesenteric lymph node (MLN) from 6-7 pigs per challenge group were also tested using EIA and QuIC. Results: PrPSc was not detected by EIA and IHC in any RPLNs. All tonsils and MLNs were negative by IHC, though the MLN from one pig in the oral <6 5="" 6="" at="" by="" detected="" eia.="" examined="" group="" in="" intracranial="" least="" lymphoid="" month="" months="" of="" one="" pigs="" positive="" prpsc="" quic="" the="" tissues="" was="">6 months group, 5/6 pigs in the oral <6 4="" and="" group="" months="" oral="">6 months group. Overall, the MLN was positive in 14/19 (74%) of samples examined, the RPLN in 8/18 (44%), and the tonsil in 10/25 (40%). 6>6>6>
<6 challenge="" groups="" month="" pigs="" remaining="" the=""><6 5="" 6="" at="" by="" detected="" eia.="" examined="" group="" in="" intracranial="" least="" lymphoid="" month="" months="" of="" one="" pigs="" positive="" prpsc="" quic="" the="" tissues="" was=""><6 4="" and="" group="" months="" oral="">
6>6>6>
This study demonstrates that PrPSc accumulates in lymphoid tissues from pigs challenged intracranially or orally with the CWD agent, and can be detected as early as 4 months after challenge.
CWD-infected pigs rarely develop clinical disease and if they do, they do so after a long incubation period.
This raises the possibility that CWD-infected pigs could shed prions into their environment long before they develop clinical disease.
Furthermore, lymphoid tissues from CWD-infected pigs could present a potential source of CWD infectivity in the animal and human food chains.
EXPERIMENTAL PORCINE SPONGIFORM ENCEPHALOPATHY
While this clearly is a cause for concern we should not jump to the conclusion that this means that pigs will necessarily be infected by bone and meat meal fed by the oral route as is the case with cattle. ...
we cannot rule out the possibility that unrecognised subclinical spongiform encephalopathy could be present in British pigs though there is no evidence for this: only with parenteral/implantable pharmaceuticals/devices is the theoretical risk to humans of sufficient concern to consider any action.
May I, at the outset, reiterate that we should avoid dissemination of papers relating to this experimental finding to prevent premature release of the information.
3. It is particularly important that this information is not passed outside the Department, until Ministers have decided how they wish it to be handled.
But it would be easier for us if pharmaceuticals/devices are not directly mentioned at all.
Our records show that while some use is made of porcine materials in medicinal products, the only products which would appear to be in a hypothetically ''higher risk'' area are the adrenocorticotrophic hormone for which the source material comes from outside the United Kingdom, namely America China Sweden France and Germany. The products are manufactured by Ferring and Armour. A further product, ''Zenoderm Corium implant'' manufactured by Ethicon, makes use of porcine skin - which is not considered to be a ''high risk'' tissue, but one of its uses is described in the data sheet as ''in dural replacement''. This product is sourced from the United Kingdom.....
snip...see much more here ;
WEDNESDAY, APRIL 05, 2017
Disease-associated prion protein detected in lymphoid tissues from pigs challenged with the agent of chronic wasting disease
SUNDAY, APRIL 23, 2017
FDA Sec. 589.1 589.2 Substances prohibited from use in animal food or feed Animal, proteins prohibited in ruminant feed current of April 1 2016
SPONTANEOUS ATYPICAL BOVINE SPONGIFORM ENCEPHALOPATHY
***Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.***
*** WDA 2016 NEW YORK ***
We found that CWD adapts to a new host more readily than BSE and that human PrP was unexpectedly prone to misfolding by CWD prions.
In addition, we investigated the role of specific regions of the bovine, deer and human PrP protein in resistance to conversion by prions from another species.
We have concluded that the human protein has a region that confers unusual susceptibility to conversion by CWD prions.
Student Presentations Session 2
The species barriers and public health threat of CWD and BSE prions
Ms. Kristen Davenport1, Dr. Davin Henderson1, Dr. Candace Mathiason1, Dr. Edward Hoover1 1Colorado State University
Chronic wasting disease (CWD) is spreading rapidly through cervid populations in the USA. Bovine spongiform encephalopathy (BSE, mad cow disease) arose in the 1980s because cattle were fed recycled animal protein. These and other prion diseases are caused by abnormal folding of the normal prion protein (PrP) into a disease causing form (PrPd), which is pathogenic to nervous system cells and can cause subsequent PrP to misfold. CWD spreads among cervids very efficiently, but it has not yet infected humans. On the other hand, BSE was spread only when cattle consumed infected bovine or ovine tissue, but did infect humans and other species. The objective of this research is to understand the role of PrP structure in cross-species infection by CWD and BSE. To study the propensity of each species’ PrP to be induced to misfold by the presence of PrPd from verious species, we have used an in vitro system that permits detection of PrPd in real-time. We measured the conversion efficiency of various combinations of PrPd seeds and PrP substrate combinations. We observed the cross-species behavior of CWD and BSE, in addition to feline-adapted CWD and BSE. We found that CWD adapts to a new host more readily than BSE and that human PrP was unexpectedly prone to misfolding by CWD prions. In addition, we investigated the role of specific regions of the bovine, deer and human PrP protein in resistance to conversion by prions from another species.
***We have concluded that the human protein has a region that confers unusual susceptibility to conversion by CWD prions.
CWD is unique among prion diseases in its rapid spread in natural populations. BSE prions are essentially unaltered upon passage to a new species, while CWD adapts to the new species. This adaptation has consequences for surveillance of humans exposed to CWD.
Wildlife Disease Risk Communication Research Contributes to Wildlife Trust Administration Exploring perceptions about chronic wasting disease risks among wildlife and agriculture professionals and stakeholders
Zoonotic Potential of CWD Prions: An Update
Chronic wasting disease (CWD) is a widespread and highly transmissible prion disease in free-ranging and captive cervid species in North America. The zoonotic potential of CWD prions is a serious public health concern, but the susceptibility of human CNS and peripheral organs to CWD prions remains largely unresolved. We reported earlier that peripheral and CNS infections were detected in transgenic mice expressing human PrP129M or PrP129V. Here we will present an update on this project, including evidence for strain dependence and influence of cervid PrP polymorphisms on CWD zoonosis as well as the characteristics of experimental human CWD prions.
PRION 2016 TOKYO In Conjunction with Asia Pacific Prion Symposium 2016 PRION 2016 Tokyo Prion 2016
Cervid to human prion transmission
Case Western Reserve University, Cleveland, OH, United States
Prion disease is transmissible and invariably fatal. Chronic wasting disease (CWD) is the prion disease affecting deer, elk and moose, and it is a widespread and expanding epidemic affecting 22 US States and 2 Canadian provinces so far. CWD poses the most serious zoonotic prion transmission risks in North America because of huge venison consumption (>6 million deer/elk hunted and consumed annually in the USA alone), significant prion infectivity in muscles and other tissues/fluids from CWD-affected cervids, and usually high levels of individual exposure to CWD resulting from consumption of the affected animal among often just family and friends. However, we still do not know whether CWD prions can infect humans in the brain or peripheral tissues or whether clinical/asymptomatic CWD zoonosis has already occurred, and we have no essays to reliably detect CWD infection in humans. 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.
Aim 1 will prove that the classical CWD strain may infect humans in brain or peripheral lymphoid tissues at low levels by conducting systemic bioassays in a set of "humanized" Tg mouse lines expressing common human PrP variants using a number of CWD isolates at varying doses and routes. Experimental "human CWD" samples will also be generated for Aim 3.
Aim 2 will test the hypothesis that the cervid-to-human prion transmission barrier is dependent on prion strain and influenced by the host (human) PrP sequence by examining and comparing the transmission efficiency and phenotypes of several atypical/unusual CWD isolates/strains as well as a few prion strains from other species that have adapted to cervid PrP sequence, utilizing the same panel of humanized Tg mouse lines as in Aim 1.
Aim 3 will establish reliable essays for detection and surveillance of CWD infection in humans by examining in details the clinical, pathological, biochemical and in vitro seeding properties of existing and future experimental "human CWD" samples generated from Aims 1-2 and compare them with those of common sporadic human Creutzfeldt-Jakob disease (sCJD) prions.
Aim 4 will attempt to detect clinical CWD-affected human cases by examining a significant number of brain samples from prion-affected human subjects in the USA and Canada who have consumed venison from CWD-endemic areas utilizing the criteria and essays established in Aim 3. The findings from this proposal will greatly advance our understandings on the potential and characteristics of cervid prion transmission in humans, establish reliable essays for CWD zoonosis and potentially discover the first case(s) of CWD infection in humans.
Public Health Relevance There are significant and increasing human exposure to cervid prions because chronic wasting disease (CWD, a widespread and highly infectious prion disease among deer and elk in North America) continues spreading and consumption of venison remains popular, but our understanding on cervid-to-human prion transmission is still very limited, raising public health concerns. This proposal aims to define the zoonotic risks of cervid prions and set up and apply essays to detect CWD zoonosis using mouse models and in vitro methods. The findings will greatly expand our knowledge on the potentials and characteristics of cervid prion transmission in humans, establish reliable essays for such infections and may discover the first case(s) of CWD infection in humans.
Key Molecular Mechanisms of TSEs
Colorado State University-Fort Collins, Fort Collins, CO, United States
Abstract Prion diseases, or transmissible spongiform encephalopathies (TSEs), are fatal neurodegenerative diseases affecting humans, cervids, bovids, and ovids. The absolute requirement of PrPC expression to generate prion diseases and the lack of instructional nucleic acid define prions as unique infectious agents. Prions exhibit species-specific tropism, inferring that unique prion strains exist that preferentially infct certain host species and confront transmission barriers to heterologous host species. However, transmission barriers are not absolute. Scientific consensus agrees that the sheep TSE scrapie probably breached the transmission barrier to cattle causing bovine spongiform encephalopathy that subsequently breached the human transmission barrier and likely caused several hundred deaths by a new-variant form of the human TSE Creutzfeldt-Jakob disease in the UK and Europe. The impact to human health, emotion and economies can still be felt in areas like farming, blood and organ donations and the threat of a latent TSE epidemic. This precedent raises the real possibility of other TSEs, like chronic wasting disease of cervids, overcoming similar human transmission barriers. A groundbreaking discovery made last year revealed that mice infected with heterologous prion strains facing significant transmission barriers replicated prions far more readily in spleens than brains6. Furthermore, these splenic prions exhibited weakened transmission barriers and expanded host ranges compared to neurogenic prions. These data question conventional wisdom of avoiding neural tissue to avoid prion xenotransmission, when more promiscuous prions may lurk in extraneural tissues. Data derived from work previously funded by NIH demonstrate that Complement receptors CD21/35 bind prions and high density PrPC and differentially impact prion disease depending on the prion isolate or strain used. Recent advances in live animal and whole organ imaging have led us to generate preliminary data to support novel, innovative approaches to assessing prion capture and transport. We plan to test our unifying hypothesis for this proposal that CD21/35 control the processes of peripheral prion capture, transport, strain selection and xenotransmission in the following specific aims.
1. Assess the role of CD21/35 in splenic prion strain selection and host range expansion.
2. Determine whether CD21/35 and C1q differentially bind distinct prion strains
3. Monitor the effects of CD21/35 on prion trafficking in real time and space
4. Assess the role of CD21/35 in incunabular prion trafficking
Public Health Relevance Transmissible spongiform encephalopathies, or prion diseases, are devastating illnesses that greatly impact public health, agriculture and wildlife in North America and around the world. The impact to human health, emotion and economies can still be felt in areas like farming, blood and organ donations and the threat of a latent TSE epidemic. This precedent raises the real possibility of other TSEs, like chronic wasting disease (CWD) of cervids, overcoming similar human transmission barriers. Early this year Canada reported its first case of BSE in over a decade audits first case of CWD in farmed elk in three years, underscoring the need for continued vigilance and research. Identifying mechanisms of transmission and zoonoses remains an extremely important and intense area of research that will benefit human and other animal populations.
PMCA Detection of CWD Infection in Cervid and Non-Cervid Species
Colorado State University-Fort Collins, Fort Collins, CO, United States
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).***
*** Zoonotic Potential of CWD Prions: An Update Prion 2016 Tokyo ***
Saturday, April 23, 2016
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
Juan Maria Torres a, Olivier Andreoletti b, J uan-Carlos Espinosa a. Vincent Beringue c. Patricia Aguilar a, Natalia Fernandez-Borges a. and Alba Marin-Moreno a "Centro de Investigacion en Sanidad Animal ( CISA-INIA ). Valdeolmos, Madrid. Spain; b UMR INRA -ENVT 1225 Interactions Holes Agents Pathogenes. ENVT. Toulouse. France: "UR892. Virologie lmmunologie MolécuIaires, Jouy-en-Josas. France
Dietary exposure to bovine spongiform encephalopathy (BSE) contaminated bovine tissues is considered as the origin of variant Creutzfeldt Jakob (vCJD) disease in human. To date, BSE agent is the only recognized zoonotic prion. Despite the variety of Transmissible Spongiform Encephalopathy (TSE) agents that have been circulating for centuries in farmed ruminants there is no apparent epidemiological link between exposure to ruminant products and the occurrence of other form of TSE in human like sporadic Creutzfeldt Jakob Disease (sCJD). However, the zoonotic potential of the diversity of circulating TSE agents has never been systematically assessed. The major issue in experimental assessment of TSEs zoonotic potential lies in the modeling of the ‘species barrier‘, the biological phenomenon that limits TSE agents’ propagation from a species to another. In the last decade, mice genetically engineered to express normal forms of the human prion protein has proved essential in studying human prions pathogenesis and modeling the capacity of TSEs to cross the human species barrier. To assess the zoonotic potential of prions circulating in farmed ruminants, we study their transmission ability in transgenic mice expressing human PrPC (HuPrP-Tg). Two lines of mice expressing different forms of the human PrPC (129Met or 129Val) are used to determine the role of the Met129Val dimorphism in susceptibility/resistance to the different agents. These transmission experiments confirm the ability of BSE prions to propagate in 129M- HuPrP-Tg mice and demonstrate that Met129 homozygotes may be susceptible to BSE in sheep or goat to a greater degree than the BSE agent in cattle and that these agents can convey molecular properties and neuropathological indistinguishable from vCJD. However homozygous 129V mice are resistant to all tested BSE derived prions independently of the originating species suggesting a higher transmission barrier for 129V-PrP variant. 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
why do we not want to do TSE transmission studies on chimpanzees $
5. A positive result from a chimpanzee challenged severly would likely create alarm in some circles even if the result could not be interpreted for man. I have a view that all these agents could be transmitted provided a large enough dose by appropriate routes was given and the animals kept long enough. Until the mechanisms of the species barrier are more clearly understood it might be best to retain that hypothesis.
snip...
R. BRADLEY
http://collections.europarchive.org/tna/20080102222950/http://www.bseinquiry.gov.uk/files/yb/1990/09/23001001.pdf
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
SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online
http://scrapie-usa.blogspot.com/2016/04/scrapie-ws-01-prion-diseases-in-animals.html
http://wwwnc.cdc.gov/eid/article/22/12/16-0635_article
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
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).***
*** The potential impact of prion diseases on human health was greatly magnified by the recognition that interspecies transfer of BSE to humans by beef ingestion resulted in vCJD. While changes in animal feed constituents and slaughter practices appear to have curtailed vCJD, there is concern that CWD of free-ranging deer and elk in the U.S. might also cross the species barrier. Thus, consuming venison could be a source of human prion disease. Whether BSE and CWD represent interspecies scrapie transfer or are newly arisen prion diseases is unknown. Therefore, the possibility of transmission of prion disease through other food animals cannot be ruled out. There is evidence that vCJD can be transmitted through blood transfusion. There is likely a pool of unknown size of asymptomatic individuals infected with vCJD, ***
*** and there may be asymptomatic individuals infected with the CWD equivalent.
*** These circumstances represent a potential threat to blood, blood products, and plasma supplies.
http://cdmrp.army.mil/prevfunded/nprp/NPRP_Summit_Final_Report.pdf
There is STRONG evidence of an association between ‘’regular’’ veal eating and risk of CJD (p = .0.01).
***********CJD REPORT 1994 increased risk for consumption of veal and venison and lamb***********
CREUTZFELDT JAKOB DISEASE SURVEILLANCE IN THE UNITED KINGDOM THIRD ANNUAL REPORT AUGUST 1994
Consumption of venison and veal was much less widespread among both cases and controls. For both of these meats there was evidence of a trend with increasing frequency of consumption being associated with increasing risk of CJD. (not nvCJD, but sporadic CJD...tss)
These associations were largely unchanged when attention was restricted to pairs with data obtained from relatives. ...
Table 9 presents the results of an analysis of these data.
There is STRONG evidence of an association between ‘’regular’’ veal eating and risk of CJD (p = .0.01).
Individuals reported to eat veal on average at least once a year appear to be at 13 TIMES THE RISK of individuals who have never eaten veal.
There is, however, a very wide confidence interval around this estimate. There is no strong evidence that eating veal less than once per year is associated with increased risk of CJD (p = 0.51).
The association between venison eating and risk of CJD shows similar pattern, with regular venison eating associated with a 9 FOLD INCREASE IN RISK OF CJD (p = 0.04).
There is some evidence that risk of CJD INCREASES WITH INCREASING FREQUENCY OF LAMB EATING (p = 0.02).
The evidence for such an association between beef eating and CJD is weaker (p = 0.14). When only controls for whom a relative was interviewed are included, this evidence becomes a little STRONGER (p = 0.08).
snip...
It was found that when veal was included in the model with another exposure, the association between veal and CJD remained statistically significant (p = < 0.05 for all exposures), while the other exposures ceased to be statistically significant (p = > 0.05).
snip...
In conclusion, an analysis of dietary histories revealed statistical associations between various meats/animal products and INCREASED RISK OF CJD. When some account was taken of possible confounding, the association between VEAL EATING AND RISK OF CJD EMERGED AS THE STRONGEST OF THESE ASSOCIATIONS STATISTICALLY. ...
snip...
In the study in the USA, a range of foodstuffs were associated with an increased risk of CJD, including liver consumption which was associated with an apparent SIX-FOLD INCREASE IN THE RISK OF CJD. By comparing the data from 3 studies in relation to this particular dietary factor, the risk of liver consumption became non-significant with an odds ratio of 1.2 (PERSONAL COMMUNICATION, PROFESSOR A. HOFMAN. ERASMUS UNIVERSITY, ROTTERDAM). (???...TSS)
snip...see full report ;
CJD9/10022
October 1994
Mr R.N. Elmhirst Chairman British Deer Farmers Association Holly Lodge Spencers Lane
BerksWell Coventry CV7 7BZ
Dear Mr Elmhirst,
CREUTZFELDT-JAKOB DISEASE (CJD) SURVEILLANCE UNIT REPORT
Thank you for your recent letter concerning the publication of the third annual report from the CJD Surveillance Unit. I am sorry that you are dissatisfied with the way in which this report was published.
The Surveillance Unit is a completely independant outside body and the Department of Health is committed to publishing their reports as soon as they become available. In the circumstances it is not the practice to circulate the report for comment since the findings of the report would not be amended. In future we can ensure that the British Deer Farmers Association receives a copy of the report in advance of publication.
The Chief Medical Officer has undertaken to keep the public fully informed of the results of any research in respect of CJD. This report was entirely the work of the unit and was produced completely independantly of the the Department.
The statistical results reqarding the consumption of venison was put into perspective in the body of the report and was not mentioned at all in the press release. Media attention regarding this report was low key but gave a realistic presentation of the statistical findings of the Unit. This approach to publication was successful in that consumption of venison was highlighted only once by the media ie. in the News at one television proqramme.
I believe that a further statement about the report, or indeed statistical links between CJD and consumption of venison, would increase, and quite possibly give damaging credence, to the whole issue. From the low key media reports of which I am aware it seems unlikely that venison consumption will suffer adversely, if at all.
From: TSS (216-119-163-189.ipset45.wt.net)
Subject: CWD aka MAD DEER/ELK TO HUMANS ???
Date: September 30, 2002 at 7:06 am PST
From: "Belay, Ermias"
To: Cc: "Race, Richard (NIH)" ; ; "Belay, Ermias"
Sent: Monday, September 30, 2002 9:22 AM
Subject: RE: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
Dear Sir/Madam,
In the Archives of Neurology you quoted (the abstract of which was attached to your email), we did not say CWD in humans will present like variant CJD. That assumption would be wrong. I encourage you to read the whole article and call me if you have questions or need more clarification (phone: 404-639-3091). Also, we do not claim that "no-one has ever been infected with prion disease from eating venison." Our conclusion stating that we found no strong evidence of CWD transmission to humans in the article you quoted or in any other forum is limited to the patients we investigated.
Ermias Belay, M.D. Centers for Disease Control and Prevention
-----Original Message-----
From: Sent: Sunday, September 29, 2002 10:15 AM
Subject: TO CDC AND NIH - PUB MED- 3 MORE DEATHS - CWD - YOUNG HUNTERS
Sunday, November 10, 2002 6:26 PM ......snip........end..............TSS
Thursday, April 03, 2008
A prion disease of cervids: Chronic wasting disease 2008 1: Vet Res. 2008 Apr 3;39(4):41 A prion disease of cervids: Chronic wasting disease Sigurdson CJ.
snip...
*** twenty-seven CJD patients who regularly consumed venison were reported to the Surveillance Center***,
snip... full text ;
SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online
http://scrapie-usa.blogspot.com/2016/04/scrapie-ws-01-prion-diseases-in-animals.html
http://wwwnc.cdc.gov/eid/article/22/12/16-0635_article
http://scrapie-usa.blogspot.com/
FRIDAY, APRIL 21, 2017
URGENT GLOBAL UPDATE BLOOD, TISSUE, CJD, nvCJD, GSS, BSE, CWD, SCRAPIE, TSE, PRION
MONDAY, MAY 1, 2017
Congress ignores Trump and his proposal to cut funding of medical research by $1.2 billion, instead they approved $1.39 billion for Alzheimer’s disease research, an increase of $400 million
Terry S. Singeltary Sr.
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