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Wednesday, October 07, 2015

Deer Prion Proteins Modulate the Emergence and Adaptation of Chronic Wasting Disease Strains

Deer Prion Proteins Modulate the Emergence and Adaptation of Chronic Wasting Disease Strains

 

Camilo Duque Velásquez1, Chiye Kim2, Allen Herbst1, Nathalie Daude3, Maria Carmen Garza4, Holger Wille4, Judd Aiken1 and Debbie McKenzie2#

 

+ Author Affiliations Center for Prions and Protein Folding Diseases, Department of Agriculture Food and Nutritional Sciences1 Department of Biological Sciences2 Department of Medicine3 Department of Biochemistry4, University of Alberta, Edmonton, Alberta, Canada

 

ABSTRACT

 

Transmission of chronic wasting disease (CWD) between cervids is influenced by the primary structure of the host cellular prion protein (PrPC). In white-tailed deer, PRNP alleles encode polymorphisms Q95G96 (wt), Q95S96 (S96) and H95G96 (H95) that differentially impact CWD progression. We hypothesize that transmission of CWD prions between deer expressing different allotypes of PrPC modifies the contagious agent affecting disease spread. To evaluate the transmission properties of CWD prions derived experimentally from deer of four PRNP genotypes (wt/wt, S96/wt, H95/wt or H95/S96), transgenic (tg) mice expressing wt (tg33) or S96 (tg60) alleles were challenged with these prion agents. Passage of deer CWD into tg33 mice resulted in 100% attack rates, with H95/S96 CWD having significantly longer incubation periods. Disease signs, neuropathological and PrP-res profiles in infected tg33 mice were similar between groups, indicating a prion strain (Wisc-1) common to all CWD inocula was amplified. In contrast, tg60 mice developed prion disease only when inoculated with the H95/wt and H95/S96 CWD allotypes. Serial passage in tg60 mice resulted in adaptation of a novel CWD strain (H95+) with distinct biological properties. Transmission of first-passage tg60CWD-H95+ isolates into tg33 mice, however, elicited two prion disease presentations consistent with a mixture of strains associated with different PrP-res glycotypes. Our data indicates that H95-PRNP heterozygous deer accumulated two CWD strains, whose emergence was dictated by PrPC primary structure of the recipient host. These findings suggest CWD transmission between cervids expressing distinct PrPC molecules results in generation of novel CWD strains.

 

IMPORTANCE

 

CWD prions are contagious among wild and captive cervids in North America and in Korea. We present data linking the amino acid variant Q95H in white-tailed deer cellular prion protein (PrPC) to the emergence of a novel CWD strain (H95+). We show that, upon infection, deer expressing H95-PrPC molecules accumulated a mixture of CWD strains selectively propagated depending on the PRNP genotype of the host in which passaged. Our study also demonstrates that mice expressing the deer S96-PRNP allele, previously shown to be resistant to various cervid prions, are susceptible to H95+ CWD prions. The potential for generation of novel strains raises the possibility of an expanded host range for CWD.

 

FOOTNOTES

 

↵# Address correspondence to: debbie.mckenzie@ualberta.ca Copyright © 2015 Duque Velásquez et al.

 

This is an open-access article distributed under the terms of the Creative Commons Attribution-Noncommerical-ShareAlike 3.0 Unported license, which permits unrestricted noncommerical use, distribution, and reproduction in any medium, provided the original author and source are credited.

 

snip...

 

Discussion

 

Transmission of deer H95/wt and H95/S96 CWD allotypes resulted in the emergence of

334 a distinct CWD strain (H95+). This novel prion agent was identified when CWD brain

335 homogenates from deer containing H95-PrP molecules were transmitted into tg60 mice. Passage

336 of these deer homogenates into tg33, however, resulted in a prion disease phenotype

337 indistinguishable to that observed following infection with wt/wt and S96/wt CWD. The ability

338 of H95+ deer CWD to cause clinical prion disease in tg60 mice, which have been shown to be

339 resistant to other CWD isolates, indicates that a new strain has emerged (45, 47, 48). Our data

340 shows that passage of CWD (wt/wt pool) through H95/wt and H95/S96 deer resulted in a

341 mixture of at least two CWD strains, distinguishable based on the tg-deer-PRNP genotype in

342 which they were propagated.

343

344 All deer CWD samples, upon first passage (P1) into tg33 mice, resulted in similar disease signs,

345 PrP-res and neuropathological features, suggesting expression of wt-PrPC favored the

346 propagation of a CWD strain (prion conformer) common to all inocula. We refer to this agent as

347 “Wisc-1”. Our results suggest “Wisc-1” is similar to CWD-1 described by Angers et al. (54).

348 The white-tailed deer sample analyzed in the Angers et al. study was a wt/wt CWD positive

349 isolate from Wisconsin. Whether Wisc-1 and CWD-1 are identical is difficult to ascertain as the

350 white-tailed deer agents were passaged in different transgenic mice. The H95+ CWD strain

351 differs from Wisc-1, CWD-1 and CWD-2 strains (54, 55).

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352

353 We found that inoculation of H95/S96 CWD into tg33 mice resulted in significantly different

354 incubation periods compared to other CWD allotypes. The absence of wt-PrPCWD in this

355 inoculum and, thus, the lack of homologous prion conversion likely contributed to the prolonged

356 incubation period. The presence of more than one prion conformer within this inoculum may

357 result in competition between agents, leading to propagation interference and extension of the

358 incubation periods (56-59).

359

360 Incubation periods were not statistically different between tg33 mice infected with wt/wt,

361 H95/wt or S96/wt CWD. Additionally, all tg33 mice presented the same prion disease phenotype

362 irrespective of the CWD inocula they received. One possible interpretation for the phenotypic

363 similarities observed between tg33 mice is the “Wisc-1” conformers have adaptive advantage in

364 hosts (either in deer or tg mice) expressing wt-PrPC. Differences in incubation periods between

365 H95/wt and H95/S96 infected tg33 mice suggest that the PrPC sequence in these deer impacted

366 the proportion of accumulated CWD strains. It has previously been demonstrated in hamster co367

infection experiments that the ratio of strains in a prion mixture influences the emergence of the

368 fastest replicating or dominant strain (56, 57, 59).

369

370 The differential susceptibility to prion infection is modulated by PrPC amino acid variability and

371 the invading prion strain (15, 17, 20, 21, 25, 26, 60). Both natural and experimental infections

372 support the association of the S96-PrPC with reduced susceptibility and slower progression of

373 CWD (3, 42-48, 55). Tg60 (S96-PrPC) mice were previously shown to be resistant to CWD

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isolates from different cervid 374 species (47, 48). In our study, tg60 mice inoculated with wt/wt and

375 S96/wt did not present with clinical disease after > 700 dpi, however, mice receiving H95/wt and

376 H95/S96 CWD allotypes developed disease signs and presented consistent neuropathology and

377 PrP-res glycotypes. Second passage of tg60CWD-H95+ isolates into tg60 mice resulted in

378 reduction of the incubation periods and similar phenotypic characteristics.

379

380 Allogenic transmission of the first passage tg60CWD-H95+ isolates into tg33 resulted in mice

381 developing two distinct prion disease phenotypes resembling the “Wisc-1” and “H95+” prion

382 strains. While some animals presented with hyperactivity and displayed widespread

383 accumulation of disease associated-PrP in brain as well as high molecular weight PrP-res, others

384 were lethargic with localized PrPCWD deposits and a distinct PrP-res glycotype. Transmission of

385 diluted tg60CWD-H95+ inoculum resulted in more mice presenting the tg60-like phenotype. This

386 suggests the tg60 donor mouse, which preferentially amplified the H95+ strain, contained a

387 persistent Wisc-1 fraction that was amplified upon passage at high dose (10% Bh) in tg33 mice.

388 Transmission of lower doses of the inoculum, likely altered the proportion of the two-prion

389 conformers, favoring the propagation of the H95+ strain. A similar outcome is observed when

390 dilutions of TME were passaged in hamsters, resulting in the isolation of the Hyper and Drowsy

391 strains (56). Transmission of tg60CWD-H95+ isolates into tg33 mice indicates that individual

392 tg60 mice accumulated CWD agent mixtures. Although prion transmission experiments in tg

393 mice do not always recapitulate what is observed in the wild (i.e., tg60 mice are resistant to a

394 number of different CWD strains whereas 96S homozygous deer are naturally infected), natural

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scrapie and CWD isolates have 395 been shown to contain strain mixtures that can be differentiated

396 by serial passage in mouse models or by histopathological and biochemical analyses (54, 61-63).

397

398 Deer with S96-PRNP alleles can be infected with CWD but have extended preclinical periods

399 suggesting they could shed infectivity over longer periods of time compared to wt homozygous

400 deer (45, 46, 48). Additionally, in CWD endemic areas, white-tailed deer with S96-PRNP alleles

401 likely have a fitness advantage compared to the more susceptible deer genotypes and, as a result,

402 the “resistant” allele may become more abundant in the population (64). An increase in the S96-

403 PRNP allele frequency could also affect the potential for selection of CWD strains able to infect

404 resistant genotypes. Likewise, other PRNP alleles associated with extension of the CWD pre405

clinical phase, such as H95-PRNP, could also be subjected to disease-driven increase in white406

tailed deer populations. Our transmission data shows that deer expressing H95-PrP accumulate a

407 CWD strain capable of infecting S96-PRNP genotypes unlike other CWD agents. An increase in

408 the frequency of H95-PRNP would also increase the likelihood of emergence of H95+ CWD

409 prions. Our data suggest that white-tailed deer expressing different PrPC allotypes can

410 accumulate and transmit CWD strain mixtures.

411

412 CWD epizootics involve multiple factors including the contagious nature of the agent, host413

pathogen interactions, agent “strains” and cervid population genetics. Our data indicates CWD

414 strain emergence is modulated by amino acid polymorphisms in the cervid PrP. CWD

415 transmission between hosts with different PRNP genotypes (65) has the potential to generate and

416 select novel prion conformations. Deer expressing H95-PrPC accumulate CWD prions with

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different transmission properties 417 as exemplified by its ability to infect "resistant" S96-PRNP

418 mice. Finally, our study highlights the importance of characterizing the diversity of CWD strains

419 and their potential for interspecies transmission, as various mammalian species are susceptible to

420 experimental CWD infection (66-69). Although several lines of evidence suggest that humans

421 are resistant to CWD prions (70-73), not all CWD strains have been tested for their zoonotic

422 potential. Our results demonstrating that H95+ deer CWD have different transmission properties

423 than CWD prions composed of wt- or S96-PrP suggest the need for evaluation of the

424 transmissibility of CWD allotypes.

 


 

P35

 

ADAPTATION OF CHRONIC WASTING DISEASE (CWD) INTO HAMSTERS, EVIDENCE OF A WISCONSIN STRAIN OF CWD

 

Chad Johnson1, Judd Aiken2,3,4 and Debbie McKenzie4,5 1 Department of Comparative Biosciences, University of Wisconsin, Madison WI, USA 53706 2 Department of Agriculture, Food and Nutritional Sciences, 3 Alberta Veterinary Research Institute, 4.Center for Prions and Protein Folding Diseases, 5 Department of Biological Sciences, University of Alberta, Edmonton AB, Canada T6G 2P5

 

The identification and characterization of prion strains is increasingly important for the diagnosis and biological definition of these infectious pathogens. Although well-established in scrapie and, more recently, in BSE, comparatively little is known about the possibility of prion strains in chronic wasting disease (CWD), a disease affecting free ranging and captive cervids, primarily in North America. We have identified prion protein variants in the white-tailed deer population and demonstrated that Prnp genotype affects the susceptibility/disease progression of white-tailed deer to CWD agent. The existence of cervid prion protein variants raises the likelihood of distinct CWD strains. Small rodent models are a useful means of identifying prion strains. We intracerebrally inoculated hamsters with brain homogenates and phosphotungstate concentrated preparations from CWD positive hunter-harvested (Wisconsin CWD endemic area) and experimentally infected deer of known Prnp genotypes. These transmission studies resulted in clinical presentation in primary passage of concentrated CWD prions. Subclinical infection was established with the other primary passages based on the detection of PrPCWD in the brains of hamsters and the successful disease transmission upon second passage. Second and third passage data, when compared to transmission studies using different CWD inocula (Raymond et al., 2007) indicate that the CWD agent present in the Wisconsin white-tailed deer population is different than the strain(s) present in elk, mule-deer and white-tailed deer from the western United States endemic region.

 


 

PPo3-7:

 

Prion Transmission from Cervids to Humans is Strain-dependent

 

Qingzhong Kong, Shenghai Huang,*Fusong Chen, Michael Payne, Pierluigi Gambetti and Liuting Qing Department of Pathology; Case western Reserve University; Cleveland, OH USA *Current address: Nursing Informatics; Memorial Sloan-Kettering Cancer Center; New York, NY USA

 

Key words: CWD, strain, human transmission

 

Chronic wasting disease (CWD) is a widespread prion disease in cervids (deer and elk) in North America where significant human exposure to CWD is likely and zoonotic transmission of CWD is a concern. Current evidence indicates a strong barrier for transmission of the classical CWD strain to humans with the PrP-129MM genotype. A few recent reports suggest the presence of two or more CWD strains. What remain unknown is whether individuals with the PrP-129VV/MV genotypes are also resistant to the classical CWD strain and whether humans are resistant to all natural or adapted cervid prion strains. Here we report that a human prion strain that had adopted the cervid prion protein (PrP) sequence through passage in cervidized transgenic mice efficiently infected transgenic mice expressing human PrP, indicating that the species barrier from cervid to humans is prion strain-dependent and humans can be vulnerable to novel cervid prion strains. Preliminary results on CWD transmission in transgenic mice expressing human PrP-129V will also be discussed.

 

Acknowledgement Supported by NINDS NS052319 and NIA AG14359.

 

PPo2-27:

 

Generation of a Novel form of Human PrPSc by Inter-species Transmission of Cervid Prions

 

Marcelo A. Barria,1 Glenn C. Telling,2 Pierluigi Gambetti,3 James A. Mastrianni4 and Claudio Soto1 1Mitchell Center for Alzheimer's disease and related Brain disorders; Dept of Neurology; University of Texas Houston Medical School; Houston, TX USA; 2Dept of Microbiology, Immunology & Molecular Genetics and Neurology; Sanders Brown Center on Aging; University of Kentucky Medical Center; Lexington, KY USA; 3Institute of Pathology; Case western Reserve University; Cleveland, OH USA; 4Dept of Neurology; University of Chicago; Chicago, IL USA

 

Prion diseases are infectious neurodegenerative disorders affecting humans and animals that result from the conversion of normal prion protein (PrPC) into the misfolded and infectious prion (PrPSc). Chronic wasting disease (CWD) of cervids is a prion disorder of increasing prevalence within the United States that affects a large population of wild and captive deer and elk. CWD is highly contagious and its origin, mechanism of transmission and exact prevalence are currently unclear. The risk of transmission of CWD to humans is unknown. Defining that risk is of utmost importance, considering that people have been infected by animal prions, resulting in new fatal diseases. To study the possibility that human PrPC can be converted into the infectious form by CWD PrPSc we performed experiments using the Protein Misfolding Cyclic Amplification (PMCA) technique, which mimic in vitro the process of prion replication. Our results show that cervid PrPSc can induce the pathological conversion of human PrPC, but only after the CWD prion strain has been stabilized by successive passages in vitro or in vivo. Interestingly, this newly generated human PrPSc exhibits a distinct biochemical pattern that differs from any of the currently known forms of human PrPSc, indicating that it corresponds to a novel human prion strain. Our findings suggest that CWD prions have the capability to infect humans, and that this ability depends on CWD strain adaptation, implying that the risk for human health progressively increases with the spread of CWD among cervids.

 

PPo2-7:

 

Biochemical and Biophysical Characterization of Different CWD Isolates

 

Martin L. Daus and Michael Beekes Robert Koch Institute; Berlin, Germany

 

Key words: CWD, strains, FT-IR, AFM

 

Chronic wasting disease (CWD) is one of three naturally occurring forms of prion disease. The other two are Creutzfeldt-Jakob disease in humans and scrapie in sheep. CWD is contagious and affects captive as well as free ranging cervids. As long as there is no definite answer of whether CWD can breach the species barrier to humans precautionary measures especially for the protection of consumers need to be considered. In principle, different strains of CWD may be associated with different risks of transmission to humans. Sophisticated strain differentiation as accomplished for other prion diseases has not yet been established for CWD. However, several different findings indicate that there exists more than one strain of CWD agent in cervids. We have analysed a set of CWD isolates from white-tailed deer and could detect at least two biochemically different forms of disease-associated prion protein PrPTSE. Limited proteolysis with different concentrations of proteinase K and/or after exposure of PrPTSE to different pH-values or concentrations of Guanidinium hydrochloride resulted in distinct isolate-specific digestion patterns. Our CWD isolates were also examined in protein misfolding cyclic amplification studies. This showed different conversion activities for those isolates that had displayed significantly different sensitivities to limited proteolysis by PK in the biochemical experiments described above. We further applied Fourier transform infrared spectroscopy in combination with atomic force microscopy. This confirmed structural differences in the PrPTSE of at least two disinct CWD isolates. The data presented here substantiate and expand previous reports on the existence of different CWD strains.

 


 

UPDATED DATA ON 2ND CWD STRAIN

 

Wednesday, September 08, 2010

 

CWD PRION CONGRESS SEPTEMBER 8-11 2010

 


 

PRION 2015 CONFERENCE FT. COLLINS CWD RISK FACTORS TO HUMANS

 

*** LATE-BREAKING ABSTRACTS PRION 2015 CONFERENCE ***

 

O18

 

Zoonotic Potential of CWD Prions

 

Liuting Qing1, Ignazio Cali1,2, Jue Yuan1, Shenghai Huang3, Diane Kofskey1, Pierluigi Gambetti1, Wenquan Zou1, Qingzhong Kong1 1Case Western Reserve University, Cleveland, Ohio, USA, 2Second University of Naples, Naples, Italy, 3Encore Health Resources, Houston, Texas, USA

 

*** These results indicate that the CWD prion has the potential to infect human CNS and peripheral lymphoid tissues and that there might be asymptomatic human carriers of CWD infection.

 

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

 

***These results indicate that the CWD prion has the potential to infect human CNS and peripheral lymphoid tissues and that there might be asymptomatic human carriers of CWD infection.***

 

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P.105: RT-QuIC models trans-species prion transmission

 

Kristen Davenport, Davin Henderson, Candace Mathiason, and Edward Hoover Prion Research Center; Colorado State University; Fort Collins, CO USA

 

Conversely, FSE maintained sufficient BSE characteristics to more efficiently convert bovine rPrP than feline rPrP. Additionally, human rPrP was competent for conversion by CWD and fCWD.

 

***This insinuates that, at the level of protein:protein interactions, the barrier preventing transmission of CWD to humans is less robust than previously estimated.

 

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

 

***This insinuates that, at the level of protein:protein interactions, the barrier preventing transmission of CWD to humans is less robust than previously estimated.***

 

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

 


 

PRION2013 CONGRESSIONAL ABSTRACTS CWD

 

Sunday, August 25, 2013

 

HD.13: CWD infection in the spleen of humanized transgenic mice

 

Liuting Qing and Qingzhong Kong

 

Case Western Reserve University; Cleveland, OH USA

 

Chronic wasting disease (CWD) is a widespread prion disease in free-ranging and captive cervid species in North America, and there is evidence suggesting the existence of multiple CWD strains. The susceptibility of human CNS and peripheral organs to the various CWD prion strains remains largely unclear. Current literature suggests that the classical CWD strain is unlikely to infect human brain, but the potential for peripheral infection by CWD in humans is unknown. We detected protease-resistant PrpSc in the spleens of a few humanized transgenic mice that were intracerebrally inoculated with natural CWD isolates, but PrpSc was not detected in the brains of any of the CWD-inoculated mice. ***Our ongoing bioassays in humanized Tg mice indicate that intracerebral challenge with such PrpSc-positive humanized mouse spleen already led to prion disease in most animals. ***These results indicate that the CWD prion may have the potential to infect human peripheral lymphoid tissues.

 

Oral.15: Molecular barriers to zoonotic prion transmission: Comparison of the ability of sheep, cattle and deer prion disease isolates to convert normal human prion protein to its pathological isoform in a cell-free system

 

Marcelo A.Barria,1 Aru Balachandran,2 Masanori Morita,3 Tetsuyuki Kitamoto,4 Rona Barron,5 Jean Manson,5 Richard Kniqht,1 James W. lronside1 and Mark W. Head1

 

1National CJD Research and Surveillance Unit; Centre for Clinical Brain Sciences; School of Clinical Sciences; The University of Edinburgh; Edinburgh, UK; 2National and OIE Reference Laboratory for Scrapie and CWD; Canadian Food Inspection Agency; Ottawa Laboratory; Fallowfield. ON Canada; 3Infectious Pathogen Research Section; Central Research Laboratory; Japan Blood Products Organization; Kobe, Japan; 4Department of Neurological Science; Tohoku University Graduate School of Medicine; Sendai. Japan; 5Neurobiology Division; The Roslin Institute and R(D)SVS; University of Edinburgh; Easter Bush; Midlothian; Edinburgh, UK

 

Background. Bovine spongiform encephalopathy (BSE) is a known zoonotic prion disease, resulting in variant Creurzfeldt- Jakob disease (vCJD) in humans. In contrast, classical scrapie in sheep is thought to offer little or no danger to human health. However, a widening range of prion diseases have been recognized in cattle, sheep and deer. The risks posed by individual animal prion diseases to human health cannot be determined a priori and are difficult to assess empirically. The fundamemal event in prion disease pathogenesis is thought to be the seeded conversion of normal prion protein (PrPC) to its pathological isoform (PrPSc). Here we report the use of a rapid molecular conversion assay to test whether brain specimens from different animal prion diseases are capable of seeding the conversion of human PrPC ro PrPSc.

 

Material and Methods. Classical BSE (C-type BSE), H-type BSE, L-type BSE, classical scrapie, atypical scrapie, chronic wasting disease and vCJD brain homogenates were tested for their ability to seed conversion of human PrPC to PrPSc in protein misfolding cyclic amplification (PMCA) reactions. Newly formed human PrPSc was detected by protease digestion and western blotting using the antibody 3F4.

 

Results. C-type BSE and vCJD were found to efficiently convert PrPC to PrPSc. Scrapie failed to convert human PrPC to PrPSc. Of the other animal prion diseases tested only chronic wasting disease appeared to have the capability ro convert human PrPC to PrPSc. The results were consistent whether the human PrPC came from human brain, humanised transgenic mouse brain or from cultured human cells and the effect was more pronounced for PrPC with methionine at codon 129 compared with that with valine.

 

Conclusion. Our results show that none of the tested animal prion disease isolates are as efficient as C-type BSE and vCJD in converting human prion protein in this in vitro assay. ***However, they also show that there is no absolute barrier ro conversion of human prion protein in the case of chronic wasting disease.

 

PRION2013 CONGRESSIONAL ABSTRACTS CWD

 

Sunday, August 25, 2013

 

***Chronic Wasting Disease CWD risk factors, humans, domestic cats, blood, and mother to offspring transmission

 


 

cwd to humans ???

 

there has been no official documentation of cwd to humans on paper, to date.

 

cwd transmission studies on humans are illegal.

 

cwd transmits freely to the squirrel monkey, but not yet to the macaque, and the macaque is a bit closer to humans than the squirrel monkey.

 

still, with cwd freely transmitting to the squirrel monkey, scientist are very concerned about the cwd to human risk factor, exposure, and potential iatrogenic transmission there from.

 

85% of human TSE is sporadic cjd, and each and every one of them are up for debate as to route and source. I believe that friendly fire (iatrogenic) or the pass it forward mode of the TSE prion will be a large portion of that. all iatrogenic cjd is, is sporadic cjd until the iatrogenic event is discovered, documented, put into the academic and then the public domain, which very seldom happens due to lack of trace back efforts.

 

see what the authors said about this casual link with cwd to human with the case of Jeffrey Schwan 26 year old, and personal communications years ago with cdc about that case. see where it is stated NO STRONG evidence. so, does this mean there IS casual evidence ???? “Our conclusion stating that we found no strong evidence of CWD transmission to humans”

 

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

 

*** 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). (SEE LINK IN REPORT HERE...TSS) PLUS, THE CDC DID NOT PUT THIS WARNING OUT FOR THE WELL BEING OF THE DEER AND ELK ;

 

snip...

 


 

I urge everyone to watch this video closely...terry

 

*** you can see video here and interview with Jeff's Mom, and scientist telling you to test everything and potential risk factors for humans ***

 


 

July's Milwaukee Journal Sentinel article did prod state officials to ask CDC to investigate the cases of the three men who shared wild game feasts. The two men the CDC is still investigating were 55 and 66 years old. But there's also Kevin Boss, a Minnesota hunter who ate Barron County venison and died of CJD at 41. And there's Jeff Schwan, whose Michigan Tech fraternity brothers used to bring venison sausage back to the frat house. His mother, Terry, says that in May 2001, Jeff, 26, began complaining about his vision. A friend noticed misspellings in his e-mail, which was totally unlike him. Jeff began losing weight. He became irritable and withdrawn. By the end of June, he couldn't remember the four-digit code to open the garage door or when and how to feed his parents' cats. At a family gathering in July, he stuck to his parents and girlfriend, barely talking. "On the night we took him to the hospital, he was speaking like he was drunk or high and I noticed his pupils were so dilated I couldn't see the irises," his mother says. By then, Jeff was no longer able to do even simple things on his computer at work, and "in the hospital, he couldn't drink enough water." When he died on September 27, 2001, an autopsy confirmed he had sporadic CJD.

 

In 2000, Belay looked into three CJD cases reported by The Denver Post, two hunters who ate meat from animals killed in Wyoming and the daughter of a hunter who ate venison from a plant that processed Colorado elk. All three died of CJD before they were 30 years old. The CDC asked the USDA to kill 1,000 deer and elk in the area where the men hunted. Belay and others reported their findings in the Archives of Neurology, writing that although "circumstances suggested a link between the three cases and chronic wasting disease, they could find no 'causal' link." Which means, says Belay, "not a single one of those 1,000 deer tested positive for CWD. For all we know, these cases may be CWD. What we have now doesn't indicate a connection. That's reassuring, but it would be wrong to say it will never happen."

 

So far, says NIH researcher Race, the two Wisconsin cases pinpointed by the newspaper look like spontaneous CJD. "But we don't know how CWD would look in human brains. It probably would look like some garden-variety sporadic CJD." What the CDC will do with these cases and four others (three from Colorado and Schwan from Upper Michigan), Race says, is "sequence the prion protein from these people, inject it into mice and wait to see what the disease looks like in their brains. That will take two years."

 

CJD is so rare in people under age 30, one case in a billion (leaving out medical mishaps), that four cases under 30 is "very high," says Colorado neurologist Bosque. "Then, if you add these other two from Wisconsin [cases in the newspaper], six cases of CJD in people associated with venison is very, very high." Only now, with Mary Riley, there are at least seven, and possibly eight, with Steve, her dining companion. "It's not critical mass that matters," however, Belay says. "One case would do it for me." The chance that two people who know each other would both contact CJD, like the two Wisconsin sportsmen, is so unlikely, experts say, it would happen only once in 140 years.

 

Given the incubation period for TSEs in humans, it may require another generation to write the final chapter on CWD in Wisconsin. "Does chronic wasting disease pass into humans? We'll be able to answer that in 2022," says Race. Meanwhile, the state has become part of an immense experiment.

 


 

*** 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. ***

 


 

*** IF CWD is not a risk factor for humans, then I guess the FDA et al recalled all this CWD tainted elk tenderloin (2009 Exotic Meats USA of San Antonio, TX) for the welfare and safety of the dead elk. ...tss

 

Exotic Meats USA Announces Urgent Statewide Recall of Elk Tenderloin Because It May Contain Meat Derived From An Elk Confirmed To Have Chronic Wasting Disease

 

Contact: Exotic Meats USA 1-800-680-4375

 

FOR IMMEDIATE RELEASE -- February 9, 2009 -- Exotic Meats USA of San Antonio, TX is initiating a voluntary recall of Elk Tenderloin because it may contain meat derived from an elk confirmed to have Chronic Wasting Disease (CWD). The meat with production dates of December 29, 30 and 31, 2008 was purchased from Sierra Meat Company in Reno, NV. The infected elk came from Elk Farm LLC in Pine Island, MN and was among animals slaughtered and processed at USDA facility Noah’s Ark Processors LLC.

 

Chronic Wasting Disease (CWD) is a fatal brain and nervous system disease found in elk and deer. The disease is caused by an abnormally shaped protein called a prion, which can damage the brain and nerves of animals in the deer family. Currently, it is believed that the prion responsible for causing CWD in deer and elk is not capable of infecting humans who eat deer or elk contaminated with the prion, but the observation of animal-to-human transmission of other prion-mediated diseases, such as bovine spongiform encephalopathy (BSE), has raised a theoretical concern regarding the transmission of CWD from deer or elk to humans. At the present time, FDA believes the risk of becoming ill from eating CWD-positive elk or deer meat is remote. However, FDA strongly advises consumers to return the product to the place of purchase, rather than disposing of it themselves, due to environmental concerns.

 

Exotic Meats USA purchased 1 case of Elk Tenderloins weighing 16.9 lbs. The Elk Tenderloin was sold from January 16 – 27, 2009. The Elk Tenderloins was packaged in individual vacuum packs weighing approximately 3 pounds each. A total of six packs of the Elk Tenderloins were sold to the public at the Exotic Meats USA retail store. Consumers who still have the Elk Tenderloins should return the product to Exotic Meats USA at 1003 NE Loop 410, San Antonio, TX 78209. Customers with concerns or questions about the Voluntary Elk Recall can call 1-800-680-4375. The safety of our customer has always been and always will be our number one priority.

 

Exotic Meats USA requests that for those customers who have products with the production dates in question, do not consume or sell them and return them to the point of purchase. Customers should return the product to the vendor. The vendor should return it to the distributor and the distributor should work with the state to decide upon how best to dispose. If the consumer is disposing of the product he/she should consult with the local state EPA office.

 

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RSS Feed for FDA Recalls Information11 [what's this?12]

 


 

Thursday, May 26, 2011

 

Travel History, Hunting, and Venison Consumption Related to Prion Disease Exposure, 2006-2007 FoodNet Population Survey Journal of the American Dietetic Association Volume 111, Issue 6 , Pages 858-863, June 2011.

 


 

now, let’s see what the authors said about this casual link, personal communications years ago. see where it is stated NO STRONG evidence. so, does this mean there IS casual evidence ???? “Our conclusion stating that we found no strong evidence of CWD transmission to humans”

 

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

 

To: rr26k@nih.gov; rrace@niaid.nih.gov; ebb8@CDC.GOV

 

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 ;

 


 

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

 

*** 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.

 


 

PRICE OF CWD TSE PRION POKER GOES UP $$$

 

Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES

 

Title: Transmission of chronic wasting disease to sentinel reindeer (Rangifer tarandus tarandus)

 

Authors

 

item Moore, S - item Kunkle, Robert item Nicholson, Eric item Richt, Juergen item Hamir, Amirali item Waters, Wade item Greenlee, Justin

 

Submitted to: American College of Veterinary Pathologists Meeting Publication Type: Abstract Only Publication Acceptance Date: August 12, 2015 Publication Date: N/A

 

Technical Abstract: Chronic wasting disease (CWD) is a naturally-occurring, fatal neurodegenerative disease of North American cervids. Reindeer (Rangifer tarandus tarandus) are susceptible to CWD following oral challenge, but CWD has not been reported in free-ranging caribou (Rangifer tarandus caribou) or farmed reindeer. Potential contact between CWD-affected cervids and Rangifer species that are free-ranging or co-housed on farms presents a potential risk of CWD transmission. The aims of this study were to 1) investigate the transmission of CWD from white-tailed deer (Odocoileus virginianus; CWD-wtd), mule deer (Odocoileus hemionus; CWD-md), or elk (Cervus elaphus nelsoni; CWD-elk) to reindeer via the intracranial route, and 2) to assess for direct and indirect horizontal transmission to non-inoculated sentinels. Three groups of 5 reindeer fawns were challenged intracranially with CWD-wtd, CWD-md, or CWD-elk. Two years after challenge of inoculated reindeer, non-inoculated control reindeer were introduced into the same pen as the CWD-wtd inoculated reindeer (n=4) or into a pen adjacent to the CWD-md inoculated reindeer (n=2). Reindeer were allowed to develop clinical disease. At death/euthanasia a complete necropsy examination was performed, including immunohistochemical testing of tissues for disease-associated CWD prion protein (PrP-CWD). Intracranially challenged reindeer developed clinical disease from 21 months post-inoculation (MPI). ***PrP-CWD was detected in 5/6 sentinel reindeer although only 2/6 developed clinical disease during the study period (<57 and="" are="" both="" can="" cervid="" cwd="" directly="" div="" from="" have="" indirectly.="" mpi="" naive="" reindeer="" shown="" sources="" susceptible="" that="" to="" transmit="" various="" we="">
 


 

***PrP-CWD was detected in 5/6 sentinel reindeer although only 2/6 developed clinical disease during the study period (<57 and="" are="" both="" can="" cervid="" cwd="" directly="" div="" from="" have="" indirectly.="" mpi="" naive="" reindeer="" shown="" sources="" susceptible="" that="" to="" transmit="" various="" we="">
 

HIGHEST INFECTION RATE ON SEVERAL CWD CONFIRMED CAPTIVES

 

snip...see more here;

 

Tuesday, September 29, 2015

 

*** Transmission of chronic wasting disease to sentinel reindeer (Rangifer tarandus tarandus) can transmit CWD to naive reindeer both directly and indirectly

 

Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES

 


 

Friday, August 28, 2015

 

*** Chronic Wasting Disease CWD TSE Prion Diagnostics and subclinical infection

 


 

Saturday, September 12, 2015

 

*** In utero transmission and tissue distribution of chronic wasting disease-associated prions in free-ranging Rocky Mountain elk

 

>>>Interestingly, five of fifteen sPMCA positive dams showed no evidence of PrPCWD in either CNS or LRS, sites typically assessed in diagnosing CWD. Analysis of fetal tissues harvested from the fifteen sPMCA positive dams revealed PrPCWD in 80% of fetuses (12/15), regardless of gestational stage. These findings demonstrate that PrPCWD is more abundant in peripheral tissues of CWD exposed elk than current diagnostic methods suggest, and that transmission of prions from mother to offspring may contribute to the efficient transmission of the CWD in naturally exposed cervid populations.<<<

 


 

P.141: Abundant prion shedding in CWD-infected deer revealed by Realtime conversion

 

Edward A Hoover,1 Davin M Henderson,1 Nathaniel D Denkers,1 Candace K Mathiason,1 Matteo Manca,2,3 and Byron Caughey2 1Prion Research Center, Colorado State University; Fort Collins, CO USA; 2Laboratory of Persistent Viral Diseases, NI AID; Hamilton, MT USA; 3Department of Biomedical Sciences, University of Cagliari; Monserrato, Italy

 

Background/Introduction. Chronic wasting disease (CWD) is unique among prion diseases in its efficient lateral transmission in nature. While the presence of infectious prions in body fluids and excreta of infected cervids has been demonstrated by bioassay, the dynamics, magnitude, and consequences of prion shedding remain unknown. The present studies were undertaken to determine the kinetics, duration, and magnitude of prion shedding in infected white-tailed deer.

 

Materials and Methods. Longitudinal samples were collected from white-tailed deer over a 2-year span after either oral (n=11)] aerosol (n = 6) CWD exposure. The assay protocol employed phosphotungstic acid precipitation of either whole saliva or the pelleted fraction of urine to seed recombinant Syrian hamster prion PrP substrate in RT-QuIC reactions. Prion seeding activity was assayed in 8 replicates of each sample employing thioflavin T detection in a 96-well plate-based fluorometer. Prion seeding reaction rate was determined by taking the inverse of the time at which samples exceeded a threshold of 5 standard deviations above the mean fluorescence of negative controls (1/time to threshold). Seeding activity was quantitated by comparing the realtime conversion reaction rate to a standard curve derived from a reference bioassayed brain pool homogenate from deer with terminal CWD.

 

Results. We analyzed >200 longitudinally collected, blinded, then randomized saliva and urine samples from 17 CWDinfected and 3 uninfected white-tailed deer. We detected prion shedding as early as 3 months post exposure and sustained thereafter throughout the disease course in both aerosol and orally exposed deer. The incidence of non-specific false positive results from > 500 saliva and urine samples from negative control deer was 0.8%. By comparing real-time reaction rates for these body fluids to a bioassayed serially diluted brain control, we estimated that ≤1 ml of saliva or urine from pre-symptomatic infected deer constitutes a lethal infectious prion dose.

 

Conclusion. CWD prions are shed in saliva and urine of infected deer as early as 3 months post infection and throughout the subsequent >1.5 year course of infection. In current work we are examining the relationship of prionemia to excretion and the impact of excreted prion binding to surfaces and particulates in the environment.

 

Acknowledgments. Support: NIH-RO1-NS-061902; Morris Animal Foundation D12ZO-045

 

P.154: Urinary shedding of prions in Chronic Wasting Disease infected white-tailed deer

 

Nathaniel D Denkers,1 Davin M Henderson, 1 Candace K Mathiason,1 and Edward A Hoover1 1Prion Research Center, Department of Microbiology, Immunology, and Pathology, Colorado State University; Fort Collins, CO USA

 

Background/Introduction. Chronic wasting disease (CWD) is unique among prion diseases in its efficient lateral transmission in nature, yet the dynamics and magnitude of shedding and its immediate and long term consequences remain unknown. The present study was designed to determine the frequency and time span in which CWD prions are shed in urine from infected white-tailed deer using adapted real-time quaking-induced conversion (RT-QuIC) methodology.

 

Materials and Methods. Longitudinal urine samples were collected by free catch or catheterization over a 2-year period from oral-route infected [CWD+ (n = 11)] and aerosol-route-infected [CWD+ (n = 6); CWD- (n = 3)] white-tailed deer. High speed centrifugation pelleted material from 500 µl of urine was treated with sodium phosphotungstic acid (Na-PTA), resuspended in 0.05% SDS buffer, and used as seed in RT-QuIC assays employing recombinant Syrian hamster prion PrP substrate. Eight (8) replicates of each sample were run and prion seeding activity was recorded as thioflavin T binding fluorescence (480 nm emission) using a fluorimeter-shaker. Samples were considered positive if they crossed an established threshold (5 standard deviations above the negative mean fluorescence).

 

Results. In our oral-route inoculation studies, prion seeding activity has been demonstrated in urine collected at 6 months post-inoculation in 6 of 10 deer (11 of 80 replicates; 14%), and intermittently at later time points in all 11 CWD+ exposed deer. Our aerosol-route inoculation studies also showed prion seeding activity in urine collected at 6 months post-inoculation in 1 of 2 deer (3 of 16 replicates; 19%), and intermittently at later time points in 4 of 6 CWD+ exposed deer. Urine from sham-inoculated control deer and all baseline samples yielded 3 false-positive prion seeding activities (3 of 352 replicates; 0.8%).

 

Conclusion. CWD prions (as inferred by prion seeding activity by RT-QuIC) are shed in urine of infected deer as early as 6 months post inoculation and throughout the subsequent disease course. Further studies are in progress refining the real-time urinary prion assay sensitivity and we are examining more closely the excretion time frame, magnitude, and sample variables in relationship to inoculation route and prionemia in naturally and experimentally CWD-infected cervids.

 

Acknowledgments. Support: NIH: RO1-NS-061902 and Morris Animal Foundation: D12ZO-045 P.178: Longitudinal quantitative analysis of CWD prions shed in saliva of deer

 

Davin M Henderson, Nina Garbino, Nathaniel D Denkers, Amy V Nalls, Candace K Mathiason, and Edward A Hoover Prion Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University; Fort Collins, CO USA

 

Background/Introduction. Chronic Wasting Disease (CWD) is an emergent rapidly spreading fatal prion disease of cervids (deer, elk and moose). CWD has now been identified in 22 States (including two new states within the last year), 2 Canadian provinces, and South Korea. Shedding of infectious prions in excreta (saliva, urine, feces) may be an important factor in CWD transmission. Here we apply an adapted version of a rapid in vitro assay [real-time quaking-induced conversion (RT-QuIC)] to determine the time of onset, length, pattern, and magnitude of prion shedding in saliva of infected deer.

 

Materials and Methods. The RT-QuIC assay was performed as previously described in Henderson et al. PLoS-One (2013). Saliva samples were quantitated by comparison to a RT-QuIC reaction rate standard curve of a bioassayed obex sample from a terminally ill cervid.

 

Results. To better understand the onset and length of CWD prion shedding we analyzed >150 longitudinally collected, blinded, then randomized saliva samples from 17 CWD-infected and 3 uninfected white-tailed deer. We observed prion shedding, as detected by the RT-QuIC assay, as early as 3 months from inoculation and sustained shedding throughout the disease course in both aerosol and orally exposed deer. We estimated the infectious lethal dose of prions shed in saliva from infected deer by comparing real-time reaction rates of saliva samples to a bioassayed serially diluted brain control. Our results indicate that as little as 1 ml of saliva from pre-symptomatic infected deer constitutes a lethal CWD prion dose.

 

Conclusions. During the pre-symptomatic stage of CWD infection and throughout the course of disease deer may be shedding multiple LD50 doses per day in their saliva. CWD prion shedding through saliva and excreta may account for the unprecedented spread of this prion disease in nature.

 

Acknowledgments. Supported by NIH grant RO1-NS-061902 and grant D12ZO-045 from the Morris Animal Foundation.

 


 

Sunday, September 13, 2015

 

urine, feces, and chronic wasting disease cwd tse prion risk factors, loading up the environment

 


 

Saturday, January 31, 2015

 

European red deer (Cervus elaphus elaphus) are susceptible to Bovine Spongiform Encephalopathy BSE by Oral Alimentary route

 


 

I strenuously once again urge the FDA and its industry constituents, to make it MANDATORY that all ruminant feed be banned to all ruminants, and this should include all cervids as soon as possible for the following reasons...

 

======

 

In the USA, under the Food and Drug Administrations BSE Feed Regulation (21 CFR 589.2000) most material (exceptions include milk, tallow, and gelatin) from deer and elk is prohibited for use in feed for ruminant animals. With regards to feed for non-ruminant animals, under FDA law, CWD positive deer may not be used for any animal feed or feed ingredients. For elk and deer considered at high risk for CWD, the FDA recommends that these animals do not enter the animal feed system.

 

***However, this recommendation is guidance and not a requirement by law.

 

======

 

31 Jan 2015 at 20:14 GMT

 

*** Ruminant feed ban for cervids in the United States? ***

 

31 Jan 2015 at 20:14 GMT

 


 

TAHC 393rd Commission Meeting Chronic Wasting Disease CWD TSE Prion October 6, 2015

 


 

Saturday, October 03, 2015

 

TEXAS CHRONIC WASTING DISEASE CWD TSE PRION GOD MUST NOT BE A TEXAN 2002 TO 2015

 


 

Friday, August 14, 2015

 

Susceptibility of cattle to the agent of chronic wasting disease from elk after intracranial inoculation

 


 

Thursday, October 1, 2015

 

H-type bovine spongiform encephalopathy associated with E211K prion protein polymorphism: clinical and pathologic features in wild-type and E211K cattle following intracranial inoculation

 

Master Obi-Wan Kenobi, Kemosabe...THIS IS NOT GOOD GOOSE!...grasshopper...tonto...tss

 


 

 


 

 

Terry S. Singeltary Sr.

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