Monday, August 14, 2017

Experimental transmission of the chronic wasting disease agent to swine after oral or intracranial inoculation

Experimental transmission of the chronic wasting disease agent to swine after oral or intracranial inoculation

S. Jo Moore1,2, M. Heather West Greenlee3, Naveen Kondru3, Sireesha Manne3, Jodi D. Smith1, Robert A. Kunkle1, Anumantha Kanthasamy3 and Justin J. Greenlee1* + Author Affiliations

1Virus and Prion Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, Ames, Iowa, United States of America 2Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee, United States of America 3Department of Biomedical Sciences, Iowa State University College of Veterinary Medicine, Ames, Iowa, United States of America

ABSTRACT

Chronic wasting disease (CWD) is a naturally occurring, fatal neurodegenerative disease of cervids. The potential for swine to serve as a host for the agent of chronic wasting disease is unknown. The purpose of this study was to investigate the susceptibility of swine to the CWD agent following experimental oral or intracranial inoculation. Crossbred piglets were assigned to one of three groups: intracranially inoculated (n=20), orally inoculated (n=19), or non-inoculated (n=9). At approximately the age at which commercial pigs reach market weight, half of the pigs in each group were culled (‘market weight’ groups). The remaining pigs (‘aged’ groups) were allowed to incubate for up to 73 months post inoculation (MPI). Tissues collected at necropsy were examined for disease-associated prion protein (PrPSc) by western blotting (WB), antigen-capture immunoassay (EIA), immunohistochemistry (IHC) and in vitro real-time quaking induced conversion (RT-QuIC). Brain samples from selected pigs were also bioassayed in mice expressing porcine prion protein. Four intracranially inoculated aged pigs and one orally inoculated aged pig were positive by EIA, IHC and/or WB. Using RT-QuIC, PrPSc was detected in lymphoid and/or brain tissue from one or more pigs in each inoculated group. Bioassay was positive in 4 out of 5 pigs assayed. This study demonstrates that pigs can support low-level amplification of CWD prions, although the species barrier to CWD infection is relatively high. However, detection of infectivity in orally inoculated pigs using mouse bioassay raises the possibility that naturally exposed pigs could act as a reservoir of CWD infectivity.

IMPORTANCE We challenged domestic swine with the chronic wasting disease agent by inoculation directly into the brain (intracranially) or by oral gavage (orally). Disease-associated prion protein (PrPSc) was detected in brain and lymphoid tissues from intracranially and orally inoculated pigs as early as 8 months of age (6 months post-inoculation). Only one pig developed clinical neurologic signs suggestive of prion disease. The amount of PrPSc in the brains and lymphoid tissues of positive pigs was small, especially in orally inoculated pigs. Regardless, positive results in orally inoculated pigs suggest that it may be possible for swine to serve as a reservoir for prion disease under natural conditions.

FOOTNOTES

↵*Corresponding author: Email: justin.greenlee@ars.usda.gov This is a work of the U.S. Government and is not subject to copyright protection in the United States. Foreign copyrights may apply.


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%). Conclusions:

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.


CONFIDENTIAL

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.


 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


TUESDAY, APRIL 18, 2017 

*** EXTREME USA FDA PART 589 TSE PRION FEED LOOP HOLE STILL EXIST, AND PRICE OF POKER GOES UP ***


TUESDAY, MARCH 28, 2017 

*** Passage of scrapie to deer results in a new phenotype upon return passage to sheep ***


MONDAY, JULY 17, 2017 

National Scrapie Eradication Program May 2017 Monthly Report Fiscal Year 2017


WEDNESDAY, JULY 26, 2017 

APHIS USDA Emerging Animal Disease Preparedness and Response Plan July 2017


TUESDAY, JULY 18, 2017 

MINK FARMING USA TRANSMISSIBLE MINK ENCEPHALOPATHY TSE PRION DISEASE SURVEILLANCE AND TESTING



THURSDAY, JULY 13, 2017 

EFSA BSE Sixty cases of mad cow disease since 2001 breached feed ban likely the cause 

Scientists investigate origin of isolated BSE cases


*** 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. 



SUNDAY, AUGUST 06, 2017 

USA Chronic Wasting Disease CWD TSE Prion Emergency Response Plan Singeltary et al 


Prion Infectivity in Fat of Deer with Chronic Wasting Disease▿ Brent Race#, Kimberly Meade-White#, Richard Race and Bruce Chesebro* + Author Affiliations

Rocky Mountain Laboratories, 903 South 4th Street, Hamilton, Montana 59840 Next Section ABSTRACT

Chronic wasting disease (CWD) is a neurodegenerative prion disease of cervids. Some animal prion diseases, such as bovine spongiform encephalopathy, can infect humans; however, human susceptibility to CWD is unknown. In ruminants, prion infectivity is found in central nervous system and lymphoid tissues, with smaller amounts in intestine and muscle. In mice, prion infectivity was recently detected in fat. Since ruminant fat is consumed by humans and fed to animals, we determined infectivity titers in fat from two CWD-infected deer. Deer fat devoid of muscle contained low levels of CWD infectivity and might be a risk factor for prion infection of other species.


Prions in Skeletal Muscles of Deer with Chronic Wasting Disease Rachel C. Angers1,*, Shawn R. Browning1,*,†, Tanya S. Seward2, Christina J. Sigurdson4,‡, Michael W. Miller5, Edward A. Hoover4, Glenn C. Telling1,2,3,§ ↵* These authors contributed equally to this work. ↵† Present address: Department of Infectology, Scripps Research Institute, 5353 Parkside Drive, RF-2, Jupiter, FL 33458, USA. ↵‡ Present address: Institute of Neuropathology, University of Zurich, Schmelzbergstrasse 12, 8091 Zurich, Switzerland. + See all authors and affiliations Science 24 Feb 2006: Vol. 311, Issue 5764, pp. 1117 DOI: 10.1126/science.1122864 Article Figures & Data Info & Metrics eLetters PDF You are currently viewing the abstract.

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Abstract

The emergence of chronic wasting disease (CWD) in deer and elk in an increasingly wide geographic area, as well as the interspecies transmission of bovine spongiform encephalopathy to humans in the form of variant Creutzfeldt Jakob disease, have raised concerns about the zoonotic potential of CWD. Because meat consumption is the most likely means of exposure, it is important to determine whether skeletal muscle of diseased cervids contains prion infectivity. Here bioassays in transgenic mice expressing cervid prion protein revealed the presence of infectious prions in skeletal muscles of CWD-infected deer, demonstrating that humans consuming or handling meat from CWD-infected deer are at risk to prion exposure.


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 

 Subject: PRION 2017 CONFERENCE DECIPHERING NEURODEGENERATIVE DISORDERS VIDEO

PRION 2017 CONFERENCE DECIPHERING NEURODEGENERATIVE DISORDERS

PRION 2017 CONFERENCE VIDEO



Chronic Wasting Disease CWD TSE Prion to Humans, who makes that final call, when, or, has it already happened?

SATURDAY, JULY 29, 2017

Risk Advisory Opinion: Potential Human Health Risks from Chronic Wasting Disease CFIA, PHAC, HC (HPFB and FNIHB), INAC, Parks Canada, ECCC and AAFC


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


TUESDAY, JUNE 13, 2017

PRION 2017 CONFERENCE ABSTRACT Chronic Wasting Disease in European moose is associated with PrPSc features different from North American CWD


TUESDAY, JULY 04, 2017

*** PRION 2017 CONFERENCE ABSTRACTS ON CHRONIC WASTING DISEASE CWD TSE PRION ***


URINE

SUNDAY, JULY 16, 2017

*** Temporal patterns of chronic wasting disease prion excretion in three cervid species ***


PAGE 25 

Transmission Studies 

Mule deer transmissions of CWD were by intracerebral inoculation and compared with natural cases resulted in a more rapidly progressive clinical disease with repeated episodes of synocopy ending in coma. One control animal became affected, it is believed through contamination of inoculam (?saline). 

Further CWD transmissions were carried out by Dick Marsh into ferret, mink and squirrel monkey. Transmission occurred in all of these species with the shortest incubation period in the ferret. 



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).***



Molecular Barriers to Zoonotic Transmission of Prions

 *** chronic wasting disease, there was no absolute barrier to conversion of the human prion protein.

 *** Furthermore, the form of human PrPres produced in this in vitro assay when seeded with CWD, resembles that found in the most common human prion disease, namely sCJD of the MM1 subtype.




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.*** 


Envt.07: 

Pathological Prion Protein (PrPTSE) in Skeletal Muscles of Farmed and Free Ranging White-Tailed Deer Infected with Chronic Wasting Disease 

***The presence and seeding activity of PrPTSE in skeletal muscle from CWD-infected cervids suggests prevention of such tissue in the human diet as a precautionary measure for food safety, pending on further clarification of whether CWD may be transmissible to humans. 

Yet, it has to be noted that our assessments of PrPTSE levels in skeletal muscles were based on findings in presumably pre- or subclinically infected animals. Therefore, the concentration of PrPTSE in skeletal muscles of WTD with clinically manifest CWD may possibly exceed our estimate which refers to clinically inconspicuous animals that are more likely to enter the human food chain. Our tissue blot findings in skeletal muscles from CWD-infected WTD would be consistent with an anterograde spread of CWD prions via motor nerve fibres to muscle tissue (figure 4A). Similar neural spreading pathways of muscle infection were previously found in hamsters orally challenged with scrapie [28] and suggested by the detection of PrPTSE in muscle fibres and muscle-associated nerve fascicles of clinically-ill non-human primates challenged with BSE prions [29]. Whether the absence of detectable PrPTSE in myofibers observed in our study is a specific feature of CWD in WTD, or was due to a pre- or subclinical stage of infection in the examined animals, remains to be established. In any case, our observations support previous findings suggesting the precautionary prevention of muscle tissue from CWD-infected WTD in the human diet, and highlight the need to comprehensively elucidate of whether CWD may be transmissible to humans. While the understanding of TSEs in cervids has made substantial progress during the past few years, the assessment and management of risks possibly emanating from prions in skeletal muscles of CWD-infected cervids requires further research. 



*** 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 


PRION 2016 TOKYO 

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 


*** 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). ***

*** 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). ***

*** 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 ;


you can see more evidence here ;


TUESDAY, AUGUST 8, 2017 

Concurrence With OIE Risk Designations for Bovine Spongiform Encephalopathy [Docket No. APHIS-2016-0092]


Terry S. Singeltary Sr.

FRIDAY, AUGUST 11, 2017 

Infectivity in bone marrow from sporadic CJD patients

Bioassays in transgenic mice expressing the human prion protein revealed the presence of unexpectedly high levels of infectivity in the bone marrow from seven out of eight sCJD cases. These findings may explain the presence of blood-borne infectivity in sCJD patients. They also suggest that the distribution of prion infectivity in peripheral tissues in sCJD patients could be wider than currently believed, with potential implications for the iatrogenic transmission risk of this disease. 


THURSDAY, AUGUST 10, 2017 

Minimise transmission risk of CJD and vCJD in healthcare settings Updated 10 August 2017


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

Gibbs CJ Jr, Asher DM, Kobrine A, Amyx HL, Sulima MP, Gajdusek DC. Laboratory of Central Nervous System Studies, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892. 

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


THURSDAY, JULY 13, 2017 

TEXAS CREUTZFELDT JAKOB DISEASE CJD TSE PRION


National Prion Center could lose all funding just as concern about CWD jumping to humans rises

SATURDAY, JULY 15, 2017 

*** National Prion Center could lose all funding just as concern about CWD jumping to humans rises


*** I URGE YOU ALL TO WATCH THESE VIDEOS ***



Tracking spongiform encephalopathies in North America

Xavier Bosch

Published: August 2003


Summary;

“My name is Terry S Singeltary Sr, and I live in Bacliff, Texas. I lost my mom to hvCJD (Heidenhain variant CJD) and have been searching for answers ever since. What I have found is that we have not been told the truth. CWD in deer and elk is a small portion of a much bigger problem.”

49-year-old Singeltary is one of a number of people who have remained largely unsatisfied after being told that a close relative died from a rapidly progressive dementia compatible with spontaneous Creutzfeldt-Jakob disease (CJD). So he decided to gather hundreds of documents on transmissible spongiform encephalopathies (TSE) and realised that if Britons could get variant CJD from bovine spongiform encephalopathy (BSE), Americans might get a similar disorder from chronic wasting disease (CWD) the relative of mad cow disease seen among deer and elk in the USA. Although his feverish search did not lead him to the smoking gun linking CWD to a similar disease in North American people, it did uncover a largely disappointing situation.

Singeltary was greatly demoralised at the few attempts to monitor the occurrence of CJD and CWD in the USA. Only a few states have made CJD reportable. Human and animal TSEs should be reportable nationwide and internationally, he complained in a letter to the Journal of the American Medical Association (JAMA 2003; 285: 733). "I hope that the CDC does not continue to expect us to still believe that the 85% plus of all CJD cases which are sporadic are all spontaneous, without route or source."

Diagnosis and Reporting of Creutzfeldt-Jakob Disease

Singeltary, Sr et al. JAMA.2001; 285: 733-734. Vol. 285 No. 6, February 14, 2001 JAMA

Diagnosis and Reporting of Creutzfeldt-Jakob Disease

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

Terry S. Singeltary, Sr Bacliff, Tex

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


Until recently, CWD was thought to be confined to the wild in a small region in Colorado. But since early 2002, it has been reported in other areas, including Wisconsin, South Dakota, and the Canadian province of Saskatchewan. Indeed, the occurrence of CWD in states that were not endemic previously increased concern about a widespread outbreak and possible transmission to people and cattle.

To date, experimental studies have proven that the CWD agent can be transmitted to cattle by intracerebral inoculation and that it can cross the mucous membranes of the digestive tract to initiate infection in lymphoid tissue before invasion of the central nervous system. Yet the plausibility of CWD spreading to people has remained elusive.

Part of the problem seems to stem from the US surveillance system. CJD is only reported in those areas known to be endemic foci of CWD. Moreover, US authorities have been criticised for not having performed enough prionic tests in farm deer and elk.

Although in November last year the US Food and Drug Administration issued a directive to state public-health and agriculture officials prohibiting material from CWD-positive animals from being used as an ingredient in feed for any animal species, epidemiological control and research in the USA has been quite different from the situation in the UK and Europe regarding BSE.

"Getting data on TSEs in the USA from the government is like pulling teeth", Singeltary argues. "You get it when they want you to have it, and only what they want you to have."

Norman Foster, director of the Cognitive Disorders Clinic at the University of Michigan (Ann Arbor, MI, USA), says that "current surveillance of prion disease in people in the USA is inadequate to detect whether CWD is occurring in human beings"; adding that, "the cases that we know about are reassuring, because they do not suggest the appearance of a new variant of CJD in the USA or atypical features in patients that might be exposed to CWD. However, until we establish a system that identifies and analyses a high proportion of suspected prion disease cases we will not know for sure". The USA should develop a system modelled on that established in the UK, he points out.

Ali Samii, a neurologist at Seattle VA Medical Center who recently reported the cases of three hunters "two of whom were friends" who died from pathologically confirmed CJD, says that "at present there are insufficient data to claim transmission of CWD into humans"; adding that "[only] by asking [the questions of venison consumption and deer/elk hunting] in every case can we collect suspect cases and look into the plausibility of transmission further". Samii argues that by making both doctors and hunters more aware of the possibility of prions spreading through eating venison, doctors treating hunters with dementia can consider a possible prion disease, and doctors treating CJD patients will know to ask whether they ate venison.

CDC spokesman Ermias Belay says that the CDC "will not be investigating the [Samii] cases because there is no evidence that the men ate CWD-infected meat". He notes that although "the likelihood of CWD jumping the species barrier to infect humans cannot be ruled out 100%" and that "[we] cannot be 100% sure that CWD does not exist in humans& the data seeking evidence of CWD transmission to humans have been very limited". 



26 March 2003 

Terry S. Singeltary, retired (medically) CJD WATCH 

I lost my mother to hvCJD (Heidenhain Variant CJD). I would like to comment on the CDC's attempts to monitor the occurrence of emerging forms of CJD. Asante, Collinge et al [1] have reported that BSE transmission to the 129-methionine genotype can lead to an alternate phenotype that is indistinguishable from type 2 PrPSc, the commonest sporadic CJD. However, CJD and all human TSEs are not reportable nationally. CJD and all human TSEs must be made reportable in every state and internationally. I hope that the CDC does not continue to expect us to still believe that the 85%+ of all CJD cases which are sporadic are all spontaneous, without route/source. We have many TSEs in the USA in both animal and man. CWD in deer/elk is spreading rapidly and CWD does transmit to mink, ferret, cattle, and squirrel monkey by intracerebral inoculation. With the known incubation periods in other TSEs, oral transmission studies of CWD may take much longer. Every victim/family of CJD/TSEs should be asked about route and source of this agent. To prolong this will only spread the agent and needlessly expose others. In light of the findings of Asante and Collinge et al, there should be drastic measures to safeguard the medical and surgical arena from sporadic CJDs and all human TSEs. I only ponder how many sporadic CJDs in the USA are type 2 PrPSc? 


2 January 2000 British Medical Journal U.S. 

Scientist should be concerned with a CJD epidemic in the U.S., as well 


15 November 1999 British Medical Journal hvCJD in the USA * BSE in U.S. 


2001 FDA CJD TSE Prion Singeltary Submission



Terry S. Singeltary Sr.

Monday, April 10, 2017

Disease-associated prion protein detected in lymphoid tissues from pigs challenged with the agent of chronic wasting disease

Disease-associated prion protein detected in lymphoid tissues from pigs challenged with the agent of chronic wasting disease

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 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 months group, 5/6 pigs in the 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%). 

Conclusions: 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.

https://www.ars.usda.gov/research/publications/publication/?seqNo115=337105

CONFIDENTIAL

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. ...

http://web.archive.org/web/20031026000118/www.bseinquiry.gov.uk/files/yb/1990/08/23004001.pdf

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.

http://web.archive.org/web/20030822031154/www.bseinquiry.gov.uk/files/yb/1990/09/10007001.pdf

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. ...

http://web.archive.org/web/20030822052332/www.bseinquiry.gov.uk/files/yb/1990/09/11005001.pdf

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. ...

http://web.archive.org/web/20030822052438/www.bseinquiry.gov.uk/files/yb/1990/09/12002001.pdf

But it would be easier for us if pharmaceuticals/devices are not directly mentioned at all. ...

http://web.archive.org/web/20030518170213/www.bseinquiry.gov.uk/files/yb/1990/09/13004001.pdf

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.....

http://web.archive.org/web/20030822054419/www.bseinquiry.gov.uk/files/yb/1990/09/21009001.pdf

Porcine prion protein amyloid 

Per Hammarstr€om and Sofie Nystr€om* IFM-Department of Chemistry; Link€oping University; Link€oping, Sweden 

ABSTRACT. Mammalian prions are composed of misfolded aggregated prion protein (PrP) with amyloid-like features. 

Prions are zoonotic disease agents that infect a wide variety of mammalian species including humans. Mammals and by-products thereof which are frequently encountered in daily life are most important for human health. It is established that bovine prions (BSE) can infect humans while there is no such evidence for any other prion susceptible species in the human food chain (sheep, goat, elk, deer) and largely prion resistant species (pig) or susceptible and resistant pets (cat and dogs, respectively). PrPs from these species have been characterized using biochemistry, biophysics and neurobiology. Recently we studied PrPs from several mammals in vitro and found evidence for generic amyloidogenicity as well as cross-seeding fibril formation activity of all PrPs on the human PrP sequence regardless if the original species was resistant or susceptible to prion disease. Porcine PrP amyloidogenicity was among the studied. Experimentally inoculated pigs as well as transgenic mouse lines overexpressing porcine PrP have, in the past, been used to investigate the possibility of prion transmission in pigs. The pig is a species with extraordinarily wide use within human daily life with over a billion pigs harvested for human consumption each year. Here we discuss the possibility that the largely prion disease resistant pig can be a clinically silent carrier of replicating prions. 

KEYWORDS. prion, pig, amyloid fibril, misfolding, transmissibility, seeding, TSE, prion strain, strain adaptation

snip...

What about pigs? In several recent papers which in our view have not received sufficient attention the notion of prion resistant pigs was challenged by generation of transgenic mice with knocked out endogenous PrP and overexpressed PoPrP. Different lines of tgPoPrP mouse were proven to be susceptible to clinical disease triggered by a variety of prion strains, suggesting that the surrogate host species (mouse) and prion strain are more important than what PrP sequence it expresses for neurotoxicity to commence. In more detail, Torres and colleagues experimentally subjected transgenic mouse lines expressing porcine PrP to a number of different TSE isolates.24-26 Their studies demonstrate that prion infection is strain specific when porcine PrP is overexpressed (4x) and used as in vivo substrate. PoTg001 mice inoculated with classical scrapie, regardless of donor genotype, resisted prion disease both at first and second passage (Fig. 3b). On the other hand, Nor98 scrapie (Atypical scrapie) as well as BSE from both cattle and BoTg mouse model resulted in clinical disease in the PoTg001 mice. However, in the first generation, disease progression was slow. Incubation time until death was as long as 600 d and the hit rate was low. This indicates that disease has barely developed by the time the mice reach their natural life span limit which in this study was set to 650 d Already in the second passage the hit rate was 100 % and the incubation time was cut in half (Fig. 3b). No further shortening of incubation time was observed upon third passage. This shows that PoPrP is capable of forming infectious and neurotoxic prions in vivo if triggered by a compatible prion strain and if given enough time to develop. Both BSE and Nor98 rapidly adapts to the PoPrP host sequence, resulting in higher penetrance as well as in markedly shorter life span already in the second passage, well within the limits of normal life span for a mouse.

There are several crucial variables which impact the susceptibility of prion diseases and transmission studies.27 PrP sequence of host, PrP sequence of prion, prion strain, prion dosage, PrP expression level of host, host genetic background, route of transmission and neuroinvasiveness if peripherally infected.28 Importantly the PrP expression level corresponds to the rate of prion disease onset.1 This likely reflects 2 converging variables: a) PrP as a substrate to the prion misfolding reaction i.e. selfcatalyzed conversion and b) PrP as a mediator of neurotoxicity through interactions with misfolded PrP within prions.

The non-homologous recPrPs presented here and in,12 easily adapt to each other and form amyloid fibrils in accordance with what is seen in vivo when inoculum composed of BoPrP used to challenge mice expressing PoPrP (Fig. 3b).24-26 A review of the literature showed that BSE strains have a high degree of penetrance in both experimental and accidental transmission. Over 50% of the species reported to be susceptible to prion disease were infected by a BSE strain.19 Recent data form our lab shows that the promiscuity of BoPrP fibrils holds true also in the case of recombinant in vitro experiments. When cross-seeding human, bovine, porcine, feline and canine PrPs with any of the other, the recBoPrP seed outcompetes the other seeds in all instances except when the HuPrP acted as substrate (Data not shown). In this case recPoPrP fibrils have the highest seeding efficiency (Fig. 1). These findings in combination with the Torres experiments,24-26 implicate that a PoPrP substrate in vivo (in pigs) could adapt to an amyloidogenic prion strain of bovine or ovine prion disease and hence replicate in the new host.

For adaptation of experimental strains through multiple passages, donors are selected based on neurotoxicity (that is on TSE disease phenotype) not on basis of amyloid fibril formation. Hence the traits of transmissible amyloidotypic prion strains may be largely unexplored if these strains require more time to transform to neurotoxic strains e.g. as proposed by Baskakov’s model of deformed templating.8 There is experimental evidence for BSE transmission into pig via parenteral routes.16 with an incubation period of 2–3 years, well within what is to be considered normal lifespan. For a breeding sow in industrial scale pig farming that is 3–5 y (Bojne Andersson, personal communication).29,30 In small scale and hobby farming both sows and boars may be kept significantly longer. Collinge and Clarke.31 describe how prion titers reach transmissibility levels well before the prion burden is high enough to be neurotoxic and cause clinical disease. It is known that prion strains need time and serial passages to adapt. Knowing that pigs in modern farming are rarely kept for enough time for clinical signs to emerge in prion infected pigs it is important to be vigilant if there is a sporadic porcine spongiform encephalopathy (PSE) as has been seen in cattle (BASE) and sheep (Nor98). Hypothetically such a sporadic and then infectious event could further adapt and over a few generations have reached the point where clinical PSE is established within the time frame where pigs are being slaughtered for human consumption (Fig. 4).

FIGURE 4. Potential prion strain adaptation in pig. The red horizontal gradient indicates the hietherto unkown prion toxicity tolerance threshold for pigs, the blue vertical line indicates normal slaughter age for industrial pig farming, the green vertical line indicates the normal lifespan of a breeding sow in industrial scale pig farming, orange areas indicate window of neurotoxic prions before onset of clinical disease (dark orange indicates subclinical BSE as reported by Wells et al,16 pale orange indicate hypothetic outcome of PSE and strain adaptation. On the outmost right a potential subclinical sporadic PSE.

USE OF MATERIALS DERIVED FROM PIG IN VIEW OF PORCINE PrP AMYLOID

The pig is the most versatile species used by humans for food and other applications. Over 1,5 billion pigs are slaughtered each year worldwide for human use.32 Besides juicy pork sirloin other parts from pig are used for making remarkably diverse things such as musical instruments, china, leather, explosives, lubricants etc. Pig offal is used for human medicine, e.g., hormone preparations such as insulin and cerebrolysin, in xenographs, sutures, heparin and in gelatin for drug capsules.33,34

And that means not only pork, it means your pigskin wallet, catgut surgical suture...in tallow, in butter. It is undoubtedly in the blood supply. DC Gajdusek (From R. Rhodes ''Deadly Feast'' 35)

While the late Carleton Gajdusek had strong views in diverse areas of prion biology, according to journalist Richard Rhodes,35 he was correct on his prediction on BSE prions (vCJD) in the blood supply18 (see text box above). An opinionated scientist can sometimes be ignored due to a judgment of character and Gajdusek was certainly provocative. Notwithstanding society should remain vigilant on the possibility that Gajdusek was also prophetic on porcine prions given the exceptionally wide spread use of pigs in everyday human life and medicine. As discussed previously it is currently not established what relations transmissible neurotoxic prion strains and amyloid morphotypic mature APrP strains have. Given the hypotheses that amyloidotypic PrP conformations can transmit with low neurotoxicity.7,36 it is interesting to reflect on possible implications. Pigs are slaughtered at 6–8 months of age. Because amyloid deposition is associated with old age, this is likely far too young for spontaneous development of APrP amyloid from PoPrP as well as other amyloidogenic proteins. From the perspective of seeded amyloidogenesis it is however a potential ideal case for highly transmissible titers of APrP (Fig. 4). In such a scenario the potential of porcine prions constitutes the perfect storm, clinically silent due to neurotoxic resistance and with high titers of transmissibility. When it comes to prions CNS material is most heavily infected. In addition, however, fat tissue (to make lard and tallow) is known to harbor extraordinary amounts of amyloid in systemic amyloidoses.37 Amyloid fibrils of misfolded large proteins (AA, AL, ATTR) are notoriously hydrophobic due to the abnormal exposure of hydrophobic residues which normally in the folded structure being hidden in the protein core. The amyloid accumulation in fat tissue is likely a phase-separation from a rather hydrophilic environment in circulation toward the hydrophobic environment provided by adipocytes. Adipose tissue could in addition represent an in vivo environment well suitable for fibril formation. What about APrP?

In analysis of mice expressing Glycophosphatidylinositol, (GPI)-anchorless PrP, abdominal fat contains appreciable amounts of infectious prions in APrP isoform stained with ThS.38 Notably mice overexpressing anchorless PrP provides a silent carrier status for a long time prior to presenting symptoms and is severely afflicted by amyloid fibril formation following scrapie (RML) infection.39 Recall that this study showed that GPI-anchored PrP is needed to present clinical neurotoxicity. Evidently circulating anchorless-PrP (analogous to recPrP) is more amyloidogenic compared to GPI-anchored PrP and is poorly neuroinvasive.28 Amyloidosis is systemic in anchorless-PrP mice and is not limited to fat but is also found as extensive cardiac amyloid deposits.39 Interestingly cardiac APrP was recently reported in one BSE inoculated rhesus macaque which showed symptoms of cardiac distress prior to death from prion neurotoxicity.40 It is noteworthy that transgenic mice expressing PoPrP appear sensitive to strains with biochemical features of amyloidogenic prion strains i.e., BSE and Nor98.25,26,36 (Fig. 3b). We recently adopted the parallel inregister intermolecular b-sheet structural model of the APrP fibril from the Caughey lab to rationalize cross-seeding between various PrP sequences.12,41 It is tempting to use this structural model to speculate on the adaptation of mono-N-glycolsylated PoPrP at the expense of double-N-glycolylated PrP in the original BSE inoculum reported in the Torres experiments.25,26 In this APrP model monoglycosylated PrP at N197 is structurally compatible while N181 is not, due to burial in the in-register intermolecular cross-beta sheet (Fig. 5).

It appears that amyloidotypic prion strains, APrP, are transmissible but associated with lower neurotoxicity compared to diffuse aggregated PrP associated with synaptic PrP accumulations. It is possible that the amino acid substitutions in PoPrP compared to HuPrP and BoPrP are important for neurotoxic signal transmission (Fig. 2b, 5). The main issue hereby is that transmissibility of APrP will remain undetected unless used for surveillance. AA amyloidosis is frequent in many animals (e.g. cattle and birds) but is exceptionally rare in pigs.42 suggesting that APrP should it reside in pig fat would be traceable using newly developed screening methods.37


CONCLUDING REMARKS 

Should the topic of porcine PrP amyloid be more of a worry than of mere academic interest? Well perhaps. Prions are particularly insidious pathogens. A recent outbreak of peripheral neuropathy in human, suggests that exposure to aerosolized porcine brain is deleterious for human health.43,44 Aerosolization is a known vector for prions at least under experimental conditions.45-47 where a mere single exposure was enough for transmission in transgenic mice. HuPrP is seedable with BoPrP seeds and even more so with PoPrP seed (Fig. 1), indicating that humans could be infected by porcine APrP prions while neurotoxicity associated with spongiform encephalopathy if such a disease existed is even less clear. Importantly transgenic mice over-expressing PoPrP are susceptible to BSE and BSE passaged through domestic pigs implicating that efficient downstream neurotoxicity pathways in the mouse, a susceptible host for prion disease neurotoxicity is augmenting the TSE phenotype.25,26 Prions in silent carrier hosts can be infectious to a third species. Data from Collinge and coworkers.21 propose that species considered to be prion free may be carriers of replicating prions. Especially this may be of concern for promiscuous prion strains such as BSE.19,48 It is rather established that prions can exist in both replicating and neurotoxic conformations.49,50 and this can alter the way in which new host organisms can react upon cross-species transmission.51 The na€ıve host can either be totally resistant to prion infection as well as remain non-infectious, become a silent non-symptomatic but infectious carrier of disease or be afflicted by disease with short or long incubation time. The host can harbor and/or propagate the donor strain or convert the strain conformation to adapt it to the na€ıve host species. The latter would facilitate infection and shorten the incubation time in a consecutive event of intra-species transmission. It may be advisable to avoid procedures and exposure without proper biosafety precautions as the knowledge of silence carrier species is poor. One case of iatrogenic CJD in recipient of porcine dura mater graft has been reported in the literature.52 The significance of this finding is still unknown. The low public awareness in this matter is exemplified by the practice of using proteolytic peptide mixtures prepared from porcine brains (Cerebrolysin) as a nootropic drug. While Cerebrolysin may be beneficial for treatment of severe diseases such as vascular dementia,53 a long term follow-up of such a product for recreational use is recommended.

DISCLOSURE OF POTENTIAL CONFLICTS OF INTEREST

No potential conflicts of interest were disclosed

FUNDING

This work was supported by G€oran Gustafsson foundation, the Swedish research council Grant #2011-5804 (PH) and the Swedish Alzheimer association (SN).

REFERENCES



TUESDAY, APRIL 18, 2017 

*** EXTREME USA FDA PART 589 TSE PRION FEED LOOP HOLE STILL EXIST, AND PRICE OF POKER GOES UP ***


WEDNESDAY, MAY 17, 2017 

SHIC FUNDED STUDY SUGGESTS POTENTIAL FOR PATHOGEN TRANSMISSION VIA FEED


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

http://chronic-wasting-disease.blogspot.com/2017/04/disease-associated-prion-protein.html

Terry S. Singeltary Sr.

Bacliff, Texas USA 77518

<flounder9@verizon.net>