Monday, September 2, 2013

PRION2013 AD.22: Bovine spongiform encephalopathy, chronic wasting disease and scrapie (TSE surveillance) programs in Alberta, Canada

AD.22: Bovine spongiform encephalopathy, chronic wasting disease and scrapie (TSE surveillance) programs in Alberta, Canada
 
Hernan Ortegon,1 Eva Chow,1 Christa Coetser,3 Gerald Hauer,1 Margo Pybus2 and Ana M. Ulmer-Franco1
 
1Alberta Agriculture and Rural Development; Edmonton, AS Canada; 2Alberta Environment and Sustainable Resource Development; Edmonton, AB Canada; 3Canadian Food Inspection Agency; Calgary, AB Canada
 
Bovine spongiform encephalopathy (BSE) in cattle, Chronic Wasting Disease (CWD) in cervids, and scrapie in sheep and goats are reportable diseases under both the provincial Animal Health Act (Alberta) and the federal Health of Animals Act (Canada). Alberta Agriculture and Rural Developmemt (ARD), in collaboration with Environment and Sustainable Resource Development, the Canadian Food Inspection Agency and the livestock industry, have performed over the past 8 y enhanced surveillance for these diseases. An overview of the history, characteristics, development and evolution of these programs will be presented.
 
An integrated approach between both levels of government and provincial specialists led to the delivery of three high-quality surveillance programs in Alberta (AB): The Canada and Alberta BSE Surveillance Program (CABSESP) was initiated on July 1, 2004 to meet international requirements on BSE surveillance, to determine the prevalence of BSE and the influence of several mitigation strategies. These actions increased consumer confidence and market access for Canadian cattle and meat products. Today, Canada exports beef to more than 50 countries. The CABSESP has tested approximately 145,000 animals for BSE since 2003. Out of the 18 BSE Canadian cases, 13 were detected by the CABSESP in AB.
 
The mandatory CWD surveillance program (MCWDSP) for farmed cervids was established in AB in 2002. Under this program cervid producers are required to submit samples from all farmed cervids one year of age and older dying on farm, culled or slaughtered. The MCWDSP has opened international markets in the US, Europe, Middle East and Eastern Asia to AB farmed cervids by providing confidence to consumers on the herd's freedom from CWD. To date, only three cases of CWD in farmed cervids were detected in AB, all in 2002, which was followed by full eradication of those herds. In addition, the TSE laboratory of ARD has tested over 50,000 samples from wild cervids finding 155 cases to date in 137 mule deer, 17 white-tailed deer, and one moose.
 
Scrapie surveillance in sheep and goats has been accomplished by three programs: the AB Abattoir surveillance, which targets abattoir populations; the AB on-farm scrapie program, which targets non-registered on-farms deaths; and the National voluntary scrapie flock certification program, which targets certified flocks. TSE surveillance in AB responded to multiple challenges resulting from evolving markets, national and international animal health requirements and new scientific discoveries, evolving and adapting to new conditions thanks to the joint effort of all parties involved.
 
 
 
 
 
 
The disease was confirmed only in elk in the Republic of Korea in 2001, 2004 and 2005. Epidemiological investigations showed that CWD was introduced via importation of infected elk from Canada between 1994 and 1997.
 
 
 
 
Friday, May 13, 2011
 
Chronic Wasting Disease (CWD) outbreaks and surveillance program in the Republic of Korea Chronic Wasting Disease (CWD) outbreaks and surveillance program in the Republic of Korea
 
On 28 December 2000, information from the Canadian government showed that a total of 95 elk had been exported from farms with CWD to Korea. These consisted of 23 elk in 1994 originating from the so-called “source farm” in Canada, and 72 elk in 1997, which had been held in pre export quarantine at the “source farm”.Based on export information of CWD suspected elk from Canada to Korea, CWD surveillance program was initiated by the Ministry of Agriculture and Forestry (MAF) in 2001. All elks imported in 1997 were traced back, however elks imported in 1994 were impossible to identify. CWD control measures included stamping out of all animals in the affected farm, and thorough cleaning and disinfection of the premises.
 
In addition, nationwide clinical surveillance of Korean native cervids, and improved measures to ensure reporting of CWD suspect cases were implemented. Total of 9 elks were found to be affected. CWD was designated as a notifiable disease under the Act for Prevention of Livestock Epidemics in 2002.
 
Additional CWD cases - 12 elks and 2 elks - were diagnosed in 2004 and 2005.
 
Since February of 2005, when slaughtered elks were found to be positive, all slaughtered cervid for human consumption at abattoirs were designated as target of the CWD surveillance program.
 
Currently, CWD laboratory testing is only conducted by National Reference Laboratory on CWD, which is the Foreign Animal Disease Division (FADD) of National Veterinary Research and Quarantine Service (NVRQS).
 
In July 2010, one out of 3 elks from Farm 1 which were slaughtered for the human consumption was confirmed as positive.
 
Consequently, all cervid – 54 elks, 41 Sika deer and 5 Albino deer – were culled and one elk was found to be positive.
 
Epidemiological investigations were conducted by Veterinary Epidemiology Division (VED) of NVRQS in collaboration with provincial veterinary services.
 
Epidemiologically related farms were found as 3 farms and all cervid at these farms were culled and subjected to CWD diagnosis.
 
Three elks and 5 crossbreeds (Red deer and Sika deer) were confirmed as positive at farm 2. All cervids at Farm 3 and Farm 4 – 15 elks and 47 elks – were culled and confirmed as negative.
 
Further epidemiological investigations showed that these CWD outbreaks were linked to the importation of elks from Canada in 1994 based on circumstantial evidences.
 
In December 2010, one elk was confirmed as positive at Farm 5. Consequently, all cervid – 3 elks, 11 Manchurian Sika deer and 20 Sika deer – were culled and one Manchurian Sika deer and seven Sika deer were found to be positive.
 
This is the first report of CWD in these sub-species of deer. Epidemiological investigations found that the owner of the Farm 2 in CWD outbreaks in July 2010 had co-owned the Farm 5. In addition, it was newly revealed that one positive elk was introduced from Farm 6 of Jinju-si Gyeongsang Namdo. All cervid – 19 elks, 15 crossbreed (species unknown) and 64 Sika deer – of Farm 6 were culled, but all confirmed as negative.
 
: Corresponding author: Dr. Hyun-Joo Sohn (+82-31-467-1867, E-mail: shonhj@korea.kr)
 
2011 Pre-congress Workshop: TSEs in animals and their environment 5
 
 
 
 
 
 
 
 
 
Additional Cases of Chronic Wasting Disease in Imported Deer in Korea
 
*Tae-Yung KIM1) 3), *Hyun-Joo SHON2), *Yi-Seok JOO2), *Un-Kyong MUN2), *Kyung-Sun KANG3), *Yong-Soon LEE3)
 
1) Animal Health Division, Ministry of Agriculture & Forestry 2) National Veterinary Research & Quarantine Service 3) Department of Veterinary Public Health, College of Veterinary Medicine, Seoul National University
 
Released 2005/09/05 received 2005/01/21 accepted 2005/05/27 Keywords: Chronic Wasting Disease (CWD), horizontal transmission
 
Chronic Wasting Disease (CWD), which had previously occurred only in the U.S.A. and Canada, broke out in a farm at Chungbuk, Korea from imported Canadian deer (Aug. 8, 2001). CWD distribution, through surveillance and epidemiologic investigations, was reported for 93 deer (43 from the CWD originating farm and 50 imported with the CWD originating farm's deer) out of 144 deer (72 from the CWD originating farm and 72 imported with the CWD originating farm's deer) that were breeding at 30 different farms. On Oct. 4 and Oct. 8, 2001, additional cases of CWD were investigated. As a result of slaughtering cohabitating deer, it was verified that other imported deer from Canada were also infected with CWD. Since it was thought that this might cause horizontal transmission, 93 deer imported from Canada in 1997 and 130 cohabitating Korean deer were slaughtered and examined. There were no infected Korean deer, but CWD re-occurred on Nov. 20, 2004 and is still under investigation.
 
 
 
 
 
 
 
Wednesday, August 11, 2010
 
REPORT ON THE INVESTIGATION OF THE SIXTEENTH CASE OF BOVINE SPONGIFORM ENCEPHALOPATHY (BSE) IN CANADA
 
 
 
 
Thursday, August 19, 2010
 
REPORT ON THE INVESTIGATION OF THE SEVENTEENTH CASE OF BOVINE SPONGIFORM ENCEPHALOPATHY (BSE) IN CANADA
 
 
 
 
Friday, March 4, 2011
 
Alberta dairy cow found with mad cow disease
 
 
 
 
Tuesday, May 21, 2013
 
*** Canada, USA, Bad feed, mad cows: Why we know three BSE cases had a common origin and why the SSS policy is in full force $$$
 
 
 
 
CFIA, USDA, AND OIE SHOOT, SHOVEL, AND SHUT THE HELL UP SSS BSE TSE PRION MAD COW TYPE POLICY $$$, and the media is buying it hook, line, and sinker $$$
 
 
 
EDMONTON - Some of former Alberta premier Ralph Klein's most colourful quotes — and the reactions they elicited:
 
 
SNIP...
 
 
"This all came about through the discovery of a single, isolated case of mad cow disease in one Alberta cow on May 20th.
 
 
The farmer — I think he was a Louisiana fish farmer who knew nothing about cattle ranching.
 
 
*** I guess any self-respecting rancher would have shot, shovelled and shut up, but he didn't do that." — Klein recalls how the mad cow crisis started and rancher Marwyn Peaster's role.
 
 
The premier was speaking at the Western Governors Association meeting in Big Sky, Mont. September 2004.
 
 
 
 
 
Wednesday, December 22, 2010.
 
Manitoba veterinarian has been fined $10,000 for falsifying certification documents for U.S. bound cattle and what about mad cow disease?
 
 
 
 
CENSORSHIP IS A TERRIBLE THING $$$.
 
 
Canada has had a COVER-UP policy of mad cow disease since about the 17th case OR 18th case of mad cow disease. AFTER THAT, all FOIA request were ignored $$$.
 
THIS proves there is indeed an epidemic of mad cow disease in North America, and it has been covered up for years and years, if not for decades, and it’s getting worse $$$.
 
 
 
Thursday, February 10, 2011.
 
TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHY REPORT UPDATE CANADA FEBRUARY 2011 and how to hide mad cow disease in Canada Current as of: 2011-01-31.
 
 
 
 
Thursday, January 17, 2013.
 
Canada, U.S. agree on animal-disease measures to protect trade, while reducing human and animal health protection.
 
 
 
 
Reasons for the New Regulation Order No. 23 (as well as amending Order No. 149) of the State Committee for Veterinary Medicine name BSE as the reason for new import requirement. The legal title for Order No. 23 is "On Urgent Measures Aimed at Prevention and Elimination of BSE and Other Prion Infections in Cattle”. Neither Order explains how the threat of introduction of BSE can be addressed through the inspection of producers of all products of animal origin including fish, dairy products, poultry and pork. It is not clear what other concerns are addressed through the proposed inspections. Formal Notification of Trading Partners On August 3rd, Ukraine's Notification and Enquiry Point issued a legal Notification G/SPS/N/UKR/3/Rev.1 found on the Official WTO Website (Committee on Sanitary and Phytosanitary Measures)
 
 
 
 
Increased Atypical Scrapie Detections.
 
Press reports indicate that increased surveillance is catching what otherwise would have been unreported findings of atypical scrapie in sheep. In 2009, five new cases have been reported in Quebec, Ontario, Alberta, and Saskatchewan. With the exception of Quebec, all cases have been diagnosed as being the atypical form found in older animals. Canada encourages producers to join its voluntary surveillance program in order to gain scrapie-free status. The World Animal Health will not classify Canada as scrapie-free until no new cases are reported for seven years. The Canadian Sheep Federation is calling on the government to fund a wider surveillance program in order to establish the level of prevalence prior to setting an eradication date. Besides long-term testing, industry is calling for a compensation program for farmers who report unusual deaths in their flocks.
 
 
 
 
Thursday, February 23, 2012
 
Atypical Scrapie NOR-98 confirmed Alberta Canada sheep January 2012
 
 
 
 
Wednesday, April 4, 2012
 
20120402 - Breach of quarantine/Violation de la mise en quarantaine of an ongoing Scrapie investigation
 
 
 
 
Sunday, September 1, 2013
 
Evaluation of the Zoonotic Potential of Transmissible Mink Encephalopathy
 
We previously described the biochemical similarities between PrPres derived from L-BSE infected macaque and cortical MM2 sporadic CJD: those observations suggest a link between these two uncommon prion phenotypes in a primate model (it is to note that such a link has not been observed in other models less relevant from the human situation as hamsters or transgenic mice overexpressing ovine PrP [28]). We speculate that a group of related animal prion strains (L-BSE, c-BSE and TME) would have a zoonotic potential and lead to prion diseases in humans with a type 2 PrPres molecular signature (and more specifically type 2B for vCJD)
 
snip...
 
Together with previous experiments performed in ovinized and bovinized transgenic mice and hamsters [8,9] indicating similarities between TME and L-BSE, the data support the hypothesis that L-BSE could be the origin of the TME outbreaks in North America and Europe during the mid-1900s.
 
 
 
 
Monday, September 02, 2013
 
Atypical BSE: role of the E211K prion polymorphism
 
Research Project: TRANSMISSION, DIFFERENTIATION, AND PATHOBIOLOGY OF TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES
 
Location: Virus and Prion Research Unit
 
 
 
 
Sunday, July 21, 2013
 
Welsh Government and Food Standards Agency Wales Joint Public Consultation on the Proposed Transmissible Spongiform Encephalopathies (Wales) Regulations 2013 Singeltary Submission WG18417
 
 
 
 
Tuesday, July 2, 2013
 
APHIS USDA Administrator Message to Stakeholders: Agency Vision and Goals Eliminating ALL remaining BSE barriers to export market
 
 
 
 
Tuesday, May 21, 2013
 
Canada, USA, Bad feed, mad cows: Why we know three BSE cases had a common origin and why the SSS policy is in full force $$$
 
 
 
 
Greetings,
 
CJD surveillance in the Canada and the USA has been in place well long enough, for this same excuse (improved P/T reporting) year after year of reporting increases to be a valid excuse anymore, in my opinion.
 
I don’t buy this same old song and dance anymore.
 
it’s the same recording we hear year after year, decade after decade, happenstance of bad luck, increase is due to better surveillance, yada, yada, yada $$$
 
North America is awash in animal Transmissible Spongiform Encephalopathy TSE prion disease in many, many species. All of which are consumed/exposed in many different ways, by humans and animals.
 
This excuse ‘’improved P/T reporting’’ is old, and it is what it is, an excuse, to protect the industries that are involved. nothing has changed in almost 3 decades, except the people. it’s the same old BSe.
 
I will report on disturbing iatrogenic risk factors, cjd in the UK, and more data on the TSE prion disease in different species, and more from prion2013 as I can get it put together.
 
I want to thank Prion2013, and all the scientist and doctors and such that are working so hard to solve the many riddles of the TSE prion disease. ...TSS
 
 
 
Sunday, August 11, 2013
 
Creutzfeldt-Jakob Disease CJD cases rising North America updated report August 2013
 
Creutzfeldt-Jakob Disease CJD cases rising North America with Canada seeing an extreme increase of 48% between 2008 and 2010
 
 
 
 
Saturday, June 15, 2013
 
Canada Fraser Health Statement on Creutzfeldt-Jakob Disease outbreak
 
 
 
 
Tuesday, May 28, 2013
 
Late-in-life surgery associated with Creutzfeldt-Jakob disease: a methodological outline for evidence-based guidance
 
 
 
 
Friday, August 16, 2013
 
Creutzfeldt-Jakob disease (CJD) biannual update August 2013 U.K. and Contaminated blood products induce a highly atypical prion disease devoid of PrPres in primates
 
 
 
 
TSS
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Sunday, September 1, 2013

Evaluation of the Zoonotic Potential of Transmissible Mink Encephalopathy

Evaluation of the Zoonotic Potential of Transmissible Mink Encephalopathy

 

Emmanuel E. Comoy 1,*, Jacqueline Mikol 1, Marie-Madeleine Ruchoux 1, Valérie Durand 1, Sophie Luccantoni-Freire 1, Capucine Dehen 1, Evelyne Correia 1, Cristina Casalone 2, Juergen A. Richt 3, Justin J. Greenlee 4, Juan Maria Torres 5, Paul Brown 1 and Jean-Philippe Deslys 1

 

1 CEA, Institute of Emerging Diseases and Innovative Therapies (iMETI), Division of Prions and Related Diseases (SEPIA), Route du Panorama, BP6, 92265 Fontenay-aux-Roses, France; E-Mails: jacqueline.mikol@wanadoo.fr (J.M.); mruchoux@yahoo.fr (M.-M.R.); valerie.durand@cea.fr (V.D.); sophie.luccantoni@cea.fr (S.L.); capucine.dehen@cea.fr (C.D.); evelyne.correia@cea.fr (E.C.); paulwbrown@comcast.net (P.B.); jpdeslys@cea.fr (J-P.D.)

 

2 Istituto Zooprofilattico Sperimentale del Piemonte, Via Bologna 148, 10154 Torino, Italy; E-Mail: cristina.casalone@izsto.it (C.C.)

 

3 Kansas State University, College of Veterinary Medicine, K224B Mosier Hall, Manhattan, Kansas 66506-5601 USA; E-Mail: jricht@vet.k-state.edu

 

4 National Animal Disease Center, USDA, Agricultural Research Service, 1920 Dayton Ave, Ames, Iowa 50010 USA; E-Mail: justin.greenlee@ars.usda.gov (J.J.G.)

 

5 Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria, Madrid, Spain; E-mail: jmtorres@inia.es

 

* Author to whom correspondence should be addressed; E-Mail: emmanuel.comoy@cea.fr (E.E.C.); Tel.: +33-46-54-90-05; Fax: +33-46-54-93-19. Received: 27 June 2013; in revised form: 28 July 2013 / Accepted: 30 July 2013 / Published: 30 July 2013

 

Abstract: Successful transmission of Transmissible Mink Encephalopathy (TME) to cattle supports the bovine hypothesis for the still controversial origin of TME outbreaks. Human and primate susceptibility to classical Bovine Spongiform Encephalopathy (c-BSE) and the transmissibility of L-type BSE to macaques indicate a low cattle-to-primate species barrier. We therefore evaluated the zoonotic potential of cattle-adapted TME. In less than two years, this strain induced in cynomolgus macaques a neurological disease similar to L-BSE but distinct from c-BSE. TME derived from another donor species (raccoon) induced a similar disease with even shorter incubation periods. L-BSE and cattle-adapted TME were also transmissible to transgenic mice expressing human prion protein (PrP). Secondary transmissions to transgenic mice expressing bovine PrP maintained the features of the three tested bovine strains (cattle TME, c-BSE and L-BSE) regardless of intermediate host. Thus, TME is the third animal prion strain transmissible to both macaques and humanized transgenic mice, suggesting zoonotic potentials that should be considered in the risk analysis of animal prion diseases for human health. Moreover, the similarities between TME and L-BSE are highly suggestive of a link between these strains, and therefore the possible presence of L-BSE for many decades prior to its identification in USA and Europe.

 

Keywords: primate; prion; transgenic mice; TME; cattle; raccoon; zoonotic potential

 

1. Introduction

 

Transmissible Mink Encephalopathy (TME) is a rare prion disease affecting ranch-reared mink that was reported in four isolated outbreaks in the USA in 1947, 1961, 1963 and 1985 [1], and in several other outbreaks in Canada, East Germany, Finland and the former USSR during the same time period, with prevalence rates as high as 100% and an estimated incubation period of 6 months [2]. Epidemiological studies suggested that each outbreak was due to dietary infection. Several experimental exposures of mink to ruminant prions were performed to identify the exact origin of TME. Low efficiency and rate of transmission were observed after inoculation of mink with sheep scrapie [3] and elk-derived Chronic Wasting Disease (CWD) [4] isolates with an incubation time of 2–3 years, while a 100% success rate of transmission was obtained within 12 months post-exposure to classical Bovine Spongiform Encephalopathy (c-BSE) [5]. However, in all cases, the resulting diseases differed from TME. Conversely, TME was experimentally transmitted to cattle [6,7] inducing a prion disease distinct from c-BSE within 16 to 28 months. Experimental transmissions to conventional and transgenic rodent models suggested similarities between TME and L-BSE [8,9], an atypical cattle prion strain that was incidentally identified several years ago in aged cattle through systematic testing within the framework of the European BSE epizootic [10]. It was speculated that sporadic atypical cattle BSE (H- and/or L- type) might be at the origin of c-BSE [11,12]. These observations support the hypothesis of a bovine origin to TME.

 

Currently, classical BSE is the only animal transmissible spongiform encephalopathy (TSE) considered as a zoonotic disease, since it induces a variant of Creutzfeldt-Jakob disease (CJD) in humans [13–15]. We, and others, demonstrated that the cynomolgus macaque, previously used to demonstrate the transmissibility of human prion diseases [16], constitutes a relevant experimental model to assess the BSE risk for humans [14,17–20]. The same species was also susceptible to L-BSE [21,22], developing a disease distinct from c-BSE. Taken together, these results suggested a low cattle-to-primate species barrier and raised questions about the zoonotic potential of different bovine prion strains. We chose to assess the risk for human health linked to TME-related prion strains by evaluating the transmissibility of cattle-adapted TME in this cynomolgus macaque model, in comparison to raccoon TME as a non-ruminant source of the same prion strain. In parallel, we used transgenic mice overexpressing human or bovine prion protein (PrP) to assess the relevance of our results for human situation.

 

 2. Results and Discussion

 

2.1. Transmission of Cattle-Adapted TME in Experimental Models

 

A primate intracerebrally inoculated with the equivalent of 40 mg of a TME-infected cattle brain (second passage) developed the first neurological signs of disease after less than twenty months of incubation (Table 1). It first showed slowness and weak tremors amplifying with time. Clinical signs then evolved with ataxia, hypermetria, poor vision, and apparent cognitive impairment. Appetite remained normal during the entire 3.5 months clinical period (limited weight loss) and no behavioral changes were noticed (total survival period 23 months). The presence of cerebral spongiosis and protease-resistant prion protein (PrPres) deposition (detailed hereafter) confirmed the presence of prion disease. When another, non-ruminant, source of TME was injected, disease occurred with a similar period of survival (Table 1).

 

Table 1. Survival (incubation and clinical duration) in months of individual cynomolgus macaques exposed to different prion strains.

 

In parallel, several but not all the transgenic mice overexpressing human (Met/Met) PrP (tg650 mice) intracerebrally inoculated with cattle-adapted TME inoculum exhibited cerebral PrPres: partial transmission (75 %) occurred in humanized mice that died after about 18 months of incubation (Figure 1).

 

2.2. Transmission of other cattle prion strains

 

From these results, cattle-adapted TME represents the third cattle prion strain (together with c-BSE and L-BSE) experimentally demonstrated to be transmissible to non-human primates. We confirmed in this study the previously described transmissibility of both L-BSE and c-BSE in both experimental primates [14,21] and transgenic [23,24] models.

 

In the primate model, exposure to L-BSE-infected cattle brain induced a clinical picture with incubation time and duration of illness that are similar to those observed after exposure to cattle-adapted TME, even after exposure to as little as 2.5 mg of brain tissue (Table 1). Conversely, c-BSE infected primates developed a different clinical picture, as previously described [14,21], with longer incubation periods even when they were exposed to 100 mg of brain tissue.

 

A comparison of incubation periods confirmed and magnified the higher virulence of L-BSE for macaque compared to c-BSE, which we had previously observed [21]. Moreover, since incubation periods classically increase with the dilution of initial infectious amount in experimental prion diseases, the similarity of incubation durations for primates exposed to either 25 or 2.5 mg of L-BSE-infected brain is in favor of a substantial amount of infectivity in the brains of cattle infected with the L-BSE prion strain.

 

Figure 1. Transmission studies of bovine prion strains to transgenic mice overexpressing human (tg650) or bovine (tg110) PrP. Tg650 mice (colored in blue) were intracerebrally inoculated with 20 μl of 10 % brain homogenate from cattle infected with adapted TME, L-BSE or c-BSE strains. Tg110 mice (colored in red) were inoculated directly with the same cattle inocula, or with brains from macaques or tg650 mice previously exposed to those cattle inocula. vCJD inoculum was injected as controls. Transmission results are expressed as rates of transmission (%), number of recipient mice (in brackets), and mean ± standard deviation of their incubation periods.

 

In the model of transgenic mice overexpressing human (Met/Met) PrP (tg650 mice), an incomplete transmission rate of 25% of L-BSE was observed after an incubation period of similar duration (18 months) to those from cattle TME-exposed animals, while a 100% transmission rate was observed with c-BSE, but with longer incubations (animals were euthanized 27 months post inoculation, corresponding to the lifespan of these animals in our facilities). These observations are consistent with the results obtained with L-BSE strain by Beringue et al., in this transgenic model [24] and by Kong in another humanized mouse model [25], suggesting a less efficient transmission of L-BSE and TME than c-BSE in this transgenic model, but with a shorter evolution when it occurs.

 

The overexpression of PrP in transgenic mice is often criticized as an element helping to force the way through the species barrier and extrapolation of our results in this model to the human situation should be taken with caution, since transgenic mice expressing physiological levels of human PrP are resistant to L-BSE [26]. Nevertheless, it must be noted that these ‘physiologic’ mice are also resistant to c-BSE, impairing its relevance for assessing the zoonotic potential of animal prion strains. In any case, an efficient transmission of these prion strains to primate, possibly in the presence of a weak cattle-to-primate species barrier, may be extrapolated from our results in the macaque model, which is strengthened by the transgenic model and the current absence of any argument for a zoonotic potential of prion strains derived from other ruminants (ovine or caprine classical or atypical scrapie, wild ruminant CWD).

 

2.3. Comparative Pathologies of the Diseases Induced by the Different Cattle Prions

 

The macaque inoculated with cattle-adapted TME showed widespread cortical spongiosis similar to that in both primates exposed to L-BSE (Figure 2). The spongiosis profile for these three animals was superimposable, with less pronounced lesions in the medulla and cerebellum in cattle TME-infected animal than in L-BSE animals (Figure 3). In the c-BSE-inoculated macaques, spongiosis profiles were different, with more discrete cortical spongiosis and lesions mainly affecting the thalamus, medulla oblongata and cerebellum. When we used a non-cattle (raccoon) TME source, a similar spongiosis profile was observed but with slight modifications (cortical lesions were less pronounced and pallidum and cerebellum were virtually spared).

 

Primates inoculated with L-BSE or cattle TME exhibited a similar diffuse laminar synaptic pattern of PrPres depositions (either fine and sandy or roughly granular) but no evidence of plaques, even when stained with thioflavine T (data not shown), whereas c-BSE-infected animals had weak diffuse synaptic labeling but multiple intensely-stained PrPres aggregates and characteristic plaques [21].

 

Figure 2. Histopathology and PrPres immunostaining. Spongiosis (A–D) and PrPres deposition (E–H) in frontal cortex in primates infected with cattle-adapted TME (A, E), L-BSE (B, F), classical BSE (C, G) or raccoon TME (D, H) (original magnification x200 for spongiosis and x400 for PrPres staining). Immunostaining of PrPres was performed with 3F4 monoclonal anti-PrP antibody after proteinase K treatment as previously described [21]. No staining was observed in the brain of control healthy primates (data not shown) under these conditions.

 

Figure 3. Spongiosis profiles in infected primates. Lesional profiles (based on spongiosis) in primates exposed to cattle-adapted TME (A) L-BSE (B), c-BSE (C) and raccoon TME (D) were defined according to the scoring and areas described by Parchi et al. [27]. Spongiosis profile of c-BSE primates is depicted as the mean among 5 primates exposed to c-BSE. Frontal Cortex (FC) ,Temporal Cortex (TC), Parietal Cortex (PC), Occipital Cortex (OC), Hippocampus (HI), Entorhinal Cortex (EC),Striatum (ST), Putamen (PUT), Pallidum (PAL), Thalamus (TH), Substantia Nigra (SN), Periventricular Gray (PG), Locus coeruleus (LC), Medulla (ME), Cerebellum (granules) (CB), Cerebellum (molecular layer) (CB), Purkinje cells (PK).

 

2.3. PrPres Detection: Strain Discrimination by Proteinase K Sensitivity and Antibody Reactivity

 

We previously demonstrated that the technique that we developed for typing and classifying prion strains in small ruminants might also be used to discriminate L-BSE from c-BSE in experimentally infected macaques [21]. Briefly, this technique is based on the strain-dependent threshold of removal of the octapeptides under controlled conditions of proteolysis, in which this N-terminal region is highly resistant to proteolysis for scrapie and sporadic CJD prions, but weakly resistant for c-BSE and undetectable for L-BSE.

 

Figure 4. Electrophoretic analysis and differential sensitivity to proteolysis of PrPres in various experimental prion diseases of primates and transgenic mice overexpressing human PrP. PrPres from brain homogenates (primates or transgenic mice Tg650 overexpressing human PrP experimentally infected with cattle-adapted TME, L-BSE or c-BSE) were purified with high concentrations of proteinase K, and detected with monoclonal antibodies recognizing the octapeptide region (Saf-32) or the core (Sha-31) of the protein. The membrane blotted with Saf-32 was overexposed compared to the membrane blotted with Sha-31.

 

Under these experimental conditions, PrPres in both primates and Tg650 exposed to cattle-adapted TME behaved like PrPres derived from corresponding animals infected with L-BSE [21] (Figure 4). A 19 kDa non-glycosylated band was observed with the anti-core antibody Sha-31, with an equal distribution between mono- and diglycosylated bands. With the anti-octapeptide antibody Saf-32, almost no immunoreactivity was detectable for these animals. In parallel, c-BSE infected animals exhibited the expected features, including a 20 kDa non glycosylated band with Sha-31, predominance of diglycosylated band and a weak immunoreactivity with Saf-32 (only observable when overexposing the membrane), suggesting that c-BSE related PrPres is more resistant to proteolysis than L-BSE- or TME-related PrPres (the macaque infected with raccoon TME exhibited glycophoretic profiles and resistance to proteolysis resistance similar to the macaque infected with cattle TME, data not shown). We previously described the biochemical similarities between PrPres derived from L-BSE infected macaque and cortical MM2 sporadic CJD: those observations suggest a link between these two uncommon prion phenotypes in a primate model (it is to note that such a link has not been observed in other models less relevant from the human situation as hamsters or transgenic mice overexpressing ovine PrP [28]). We speculate that a group of related animal prion strains (L-BSE, c-BSE and TME) would have a zoonotic potential and lead to prion diseases in humans with a type 2 PrPres molecular signature (and more specifically type 2B for vCJD).

 

Strain signatures were also assessed in bioassays in transgenic mice overexpressing bovine PrP (tg110). Those mice were intracerebrally inoculated with cattle-adapted TME, L-BSE or c-BSE isolates issued from cattle, macaque or tg650 recipients (vCJD samples were also included as controls) (Figure 1). All the inoculated mice developed a TSE, with similar incubation periods whatever the source (cattle, primate, Tg650 mice or human), but related to the original prion strain: mean periods ranged from 216 to 233 days for cattle-adapted TME and from 226 to 238 days for L-BSE, while c-BSE led to longer incubation periods ranging from 309 to 362 days. This biochemical strain typing protocol was adapted (preferential use of Bar-233 antibody for protein core detection) and applied to Tg110 mice (Figure 5). The respective features (size of non glycosylated band, proportion of glycosylated forms, resistance of octapeptide regions to proteolysis) that were observed in primates and Tg650 mice for each original prion strain (cattle TME, L-BSE or c-BSE) were also observed in this model, regardless of the host from which the prion originated.

 

Figure 5. Electrophoretic analysis and differential sensitivity to proteolysis of PrPres in various experimental prion diseases of transgenic mice overexpressing bovine PrP. Transgenic mice Tg110 overexpressing bovine PrP were inoculated with brain tissue from cattle, primate, or Tg650 mice experimentally infected with cattle-adapted TME, L-BSE or c-BSE, or brain tissue from a vCJD patient. The brains were homogenized and PrPres was purified with high concentrations of proteinase K, and detected with monoclonal antibodies that recognize either the octapeptide region (Saf-32) or the core (Bar-233) of the protein. The membrane blotted with Saf-32 was overexposed compared to the membrane blotted with Bar-233.

 

3. Experimental Section

 

3.1. Ethics Statement

 

Primates and mice were housed and handled in accordance with the European Directive 2010/63 related to animal protection and welfare in research, under the constant internal surveillance of veterinarians. Animals were handled under anesthesia to limit stress, and euthanasia was performed for ethical reasons when animals lost autonomy.

 

3.2. Experimental Animals

 

Captive-bred 2-5 year-old male cynomolgus macaques (Macaca fascicularis) were provided by Noveprim (Mauritius), checked for the absence of common primate pathogens before importation, and handled in accordance to national guidelines. Transgenic mice overexpressing human (tg650 [23]) or bovine (tg110 [29]) PrP were internally bred at CEA (Fontenay-aux-Roses, France). Animals housed in level-3 animal care facilities (agreement numbers A 92-032-02 for animal care facilities, 92-189 for animal experimentation) were regularly examined at least once a week.

 

3.3. Experimental Inoculations

 

The TME inocula were derived from a second passage in cattle (#A263, [7]) or the first passage from mink to raccoon (#R5-6, [30]). The L-BSE inoculum (mix of brainstem and thalamus) was derived from an asymptomatic 15 year-old Italian Piemontese cow (#1088, [10]), and the c-BSE inocula were derived from infected UK cattle. Macaques and mice were intracerebrally (i.c.) inoculated with 1% or 10% brain homogenates in a 5% glucose solution.

 

3.4. Neuropathology and Immunohistochemistry

 

Tissues were fixed in formalin 4% for histological examination. Neuropathology and immunohistochemical detection of protease-resistant prion protein (PrPres) were performed on brain sections as previously described [21].

 

3.4. PrPres Analysis

 

PrP was purified according to the TeSeE purification protocol (Bio-Rad), in adapted conditions of proteolysis for strain discrimination as previously described [21], using Bar-233, Sha-31 or Saf-32 antibodies.

 

4. Conclusions

 

We have shown that cattle-adapted TME is the third cattle prion strain (joining classical and L-type BSE) to be transmissible both to non-human primates and transgenic mice overexpressing human PrP. However, the successful transmission of raccoon TME to primate, inducing a disease with similar features as cattle TME, extends this notion to TME-related strains independent of host origin. Pathological, biochemical and bioassay investigations converged to demonstrate the similarity between cattle-adapted TME and L-BSE. Together with previous experiments performed in ovinized and bovinized transgenic mice and hamsters [8,9] indicating similarities between TME and L-BSE, the data support the hypothesis that L-BSE could be the origin of the TME outbreaks in North America and Europe during the mid-1900s. The corollary of this notion is the longstanding existence of atypical bovine prion cases in those countries during the same period, if not earlier. Although the risk of L-BSE for public health must be further assessed through studies using the oral route of exposure before drawing definitive conclusions, these data underline the importance of a potential zoonotic risk of L-BSE in the management of consumer protection, particularly in the context of the current relaxation of European policy with respect to BSE.

 

Acknowledgments

 

The authors acknowledge Health Canada and the NIAID-NIH PO1 AI 77774-01 “Pathogenesis, Transmission and Detection of Zoonotic Prion Diseases” for funding parts of those experiments. The authors thanks J.-L. Villotte and V. Beringue for their generous gift of transgenic mice overexpressing human PrP, as well as Christophe Durand, Onofrio Bevilacqua and Sébastien Jacquin for the excellent daily care they gave to the animals.

 

Conflict of Interest

 

The CEA owns a patent covering the BSE diagnostic tests commercialized by the company Bio-Rad.

 

References

 

SNIP...

 

 


 

 


 

 

 

 

>>>We previously described the biochemical similarities between PrPres derived from L-BSE infected macaque and cortical MM2 sporadic CJD: those observations suggest a link between these two uncommon prion phenotypes in a primate model (it is to note that such a link has not been observed in other models less relevant from the human situation as hamsters or transgenic mice overexpressing ovine PrP [28]). We speculate that a group of related animal prion strains (L-BSE, c-BSE and TME) would have a zoonotic potential and lead to prion diseases in humans with a type 2 PrPres molecular signature (and more specifically type 2B for vCJD)<<<

 

 

 

2003 Singeltary Submission to FDA ;

 

 

Asante/Collinge et al have major findings on sporadic CJD, why in the hell is this not making big news in the USA? ($$$) the fact that with the new findings from Collinge et al, that BSE transmission to the 129-methionine genotype can lead to an alternate phenotype which is indistinguishable from type 2 PrPSc, the commonest sporadic CJD, i only ponder how many of the sporadic CJDs in the USA are tied to this alternate phenotype? these new findings are very serious, and should have a major impact on the way sporadic CJDs are now treated as opposed to the vCJD that was thought to be the only TSE tied to ingesting beef, in the medical/surgical arena. these new findings should have a major impact on the way sporadic CJD is ignored, and should now be moved to the forefront of research as with vCJD/nvCJD. the USA has many TSEs, the USA lacks sufficient testing for TSEs in cattle, and the USA still refuses to rapid TSE test USA cattle in sufficient numbers to find, when the late Dr. Richard Marsh had proven that mink had gone down with a TSE (TME), from being fed on 95%+ downer cattle.

 


 


 

 

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

 

Sent: Tuesday, July 29, 2003 1:03 PM

 


 

Cc: ggraber@cvm.fda.gov; Linda.Grassie@fda.gov; BSE-L

 

Subject: Docket No. 2003N-0312 Animal Feed Safety System [TSS SUBMISSION TO DOCKET 2003N-0312]

 

Greetings FDA,

 

my name is Terry S. Singeltary Sr., i lost my mother to hvCJD (Heidenhain Variant Creutzfeldt Jakob Disease).

 

i would kindly like to comment on the proposed HACCP method of detecting and or preventing TSEs in the human/animal feed supply.

 

it seems to me by implementing something that was designed for Astronauts instead of cattle, something that the GAO has already stated is terribly flawed (HACCP), i find it very disturbing to continue to insist on refusing to use rapid TSE TESTING in sufficient numbers to find TSEs, as with other Countries that they too once thought they were BSE free. for example, it took Italy 1 MILLION rapid TSE tests since 2001 to find 102 cases of BSE. THE USA has only tested 48,000 cattle in the 14 years of surveillance. there is documented proof that indeed the USA cattle have been infected with a TSE for decades, but the FDA/USDA and other USA Gov. agencies continue to conveniently ignore these findings. YOU must not ignore what Richard Marsh found. Plus, you must not ignore Asante/Collinge new findings 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. The USA has been feeding ruminant by-products back to cattle, deer, elk and sheep for decades, and TSEs in these species have been recycled for feed for decades in the USA. The rendering process here in the USA will not kill this agent. to implement any HACCP over massive rapid TSE testing is only prolonging the inevitable, and will only allow the agent to spread further. it is simply a band-aid approach to something that needs a tourniquet...

 


 

 

 

From: Terry S. Singeltary Sr. [flounder9@verizon.net]

 

Sent: Monday, July 24, 2006 1:09 PM

 

To: FSIS RegulationsComments

 

Subject: [Docket No. FSIS-2006-0011] FSIS Harvard Risk Assessment of Bovine Spongiform Encephalopathy (BSE)

 

Page 1 of 98

 

8/3/2006

 

Greetings FSIS,

 

I would kindly like to comment on the following ;

 

 


 

 

response to Singeltary et al ;

 


 

 


 

 

Monday, January 08, 2001 3:03 PM

 


 

 

 

A kind greetings from Bacliff, Texas !

 

I have often pondered if the whole damn mad cow follies started over here in the USA, and somehow, the USA shipped it over to the UK ?

 

It happened with S. Korea and CWD, via Canada. see ;

 

The disease was confirmed only in elk in the Republic of Korea in 2001, 2004 and 2005. Epidemiological investigations showed that CWD was introduced via importation of infected elk from Canada between 1994 and 1997.

 


 

 

 

but I still am not so sure that the mad cow follies did not start long ago right here in the USA i.e. Richard Marsh and deadstock downer cattle to those mink, and then the USA shipped it to hell and back. just pondering out loud here. ...tss

 

 

 

The exact same recipe for B.S.E. existed in the U.S. for years

 

and years. In reading over the Qualitative Analysis of BSE

 

Risk Factors-1, this is a 25 page report by the

 

USDA:APHIS:VS. It could have been done in one page. The

 

first page, fourth paragraph says it all;

 

"Similarities exist in the two countries usage of continuous

 

rendering technology and the lack of usage of solvents,

 

however, large differences still remain with other risk factors

 

which greatly reduce the potential risk at the national level."

 

Then, the next 24 pages tries to down-play the high risks of

 

B.S.E. in the U.S., with nothing more than the cattle to sheep

 

ratio count, and the geographical locations of herds and flocks.

 

That's all the evidence they can come up with, in the next 24

 

pages.

 

 Something else I find odd, page 16;

 

 "In the United Kingdom there is much concern for a specific

 

continuous rendering technology which uses lower

 

temperatures and accounts for 25 percent of total output. This

 

technology was _originally_ designed and imported from the

 

United States. However, the specific application in the

 

production process is _believed_ to be different in the two

 

countries."

 

 A few more factors to consider, page 15;

 

 "Figure 26 compares animal protein production for the two

 

countries. The calculations are based on slaughter numbers,

 

fallen stock estimates, and product yield coefficients. This

 

approach is used due to variation of up to 80 percent from

 

different reported sources. At 3.6 million tons, the United

 

States produces 8 times more animal rendered product than

 

the United Kingdom."

 

 "The risk of introducing the BSE agent through sheep meat and

 

bone meal is more acute in both relative and absolute terms in

 

the United Kingdom (Figures 27 and 28). Note that sheep

 

meat and bone meal accounts for 14 percent, or 61 thousand

 

tons, in the United Kingdom versus 0.6 percent or 22 thousand

 

tons in the United States. For sheep greater than 1 year, this is

 

less than one-tenth of one percent of the United States supply."

 

"The potential risk of amplification of the BSE agent through

 

cattle meat and bone meal is much greater in the United States

 

where it accounts for 59 percent of total product or almost 5

 

times more than the total amount of rendered product in the

 

United Kingdom."

 

 Considering, it would only take _one_ scrapie infected sheep

 

to contaminate the feed. Considering Scrapie has run rampant

 

in the U.S. for years, as of Aug. 1999, 950 scrapie infected

 

flocks. Also, Considering only one quarter spoonful of scrapie

 

infected material is lethal to a cow. Considering all this, the

 

sheep to cow ration is meaningless. As I said, it's 24 pages of

 

B.S.e.

 

To be continued...

 

Terry S. Singeltary Sr. P.O. Box 42 Bacliff, Texas USA

 

_____________________________________________________________________

 

 

 


 

 

snip...see full text ;

 

 

Monday, June 3, 2013

 

Unsuccessful oral transmission of scrapie from British sheep to cattle

 


 

 

Thursday, August 15, 2013

 

Stability properties of PrPSc from cattle with experimental transmissible spongiform encephalopathies: use of a rapid whole homogenate, protease-free assay

 


 

 

Sunday, July 21, 2013

 

Welsh Government and Food Standards Agency Wales Joint Public Consultation on the Proposed Transmissible Spongiform Encephalopathies (Wales) Regulations 2013 Singeltary Submission WG18417

 


 

 

 

Saturday, July 6, 2013

 

Small Ruminant Nor98 Prions Share Biochemical Features with Human Gerstmann-Sträussler-Scheinker Disease and Variably Protease-Sensitive Prionopathy

 

Research Article

 


 

 

 

Tuesday, July 21, 2009

 

Transmissible mink encephalopathy - review of the etiology

 


 

 

 

Saturday, December 01, 2007

 

Phenotypic Similarity of Transmissible Mink Encephalopathy in Cattle and L-type Bovine Spongiform Encephalopathy in a Mouse Model

 


 

 

 

Sunday, December 10, 2006

 

Transmissible Mink Encephalopathy TME

 


 


 

 

 

Thursday, March 29, 2012

 

atypical Nor-98 Scrapie has spread from coast to coast in the USA 2012

 

NIAA Annual Conference April 11-14, 2011San Antonio, Texas

 


 

 

 

Friday, July 26, 2013

 

Voluntary Scrapie Program USA UPDATE July 26, 2013 increase in FY 2013 is not statistically meaningful due to the sample size

 


 

 

 

Sunday, August 25, 2013

 

Prion2013 Chronic Wasting Disease CWD risk factors, humans, domestic cats, blood, and mother to offspring transmission

 


 

 

 

Friday, August 16, 2013

 

*** Creutzfeldt-Jakob disease (CJD) biannual update August 2013 U.K. and Contaminated blood products induce a highly atypical prion disease devoid of PrPres in primates

 


 

 

 

Sunday, August 11, 2013

 

Creutzfeldt-Jakob Disease CJD cases rising North America updated report August 2013

 

*** Creutzfeldt-Jakob Disease CJD cases rising North America with Canada seeing an extreme increase of 48% between 2008 and 2010

 


 

 

 

 

TSS
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Thursday, August 29, 2013

In vitro prion protein conversion suggests risk of bighorn sheep (Ovis canadensis) to transmissible spongiform encephalopathies

In vitro prion protein conversion suggests risk of bighorn sheep (Ovis canadensis) to transmissible spongiform encephalopathies
 
In vitro prion protein conversion suggests risk of bighorn sheep (Ovis canadensis) to transmissible spongiform encephalopathies
 
Aaron R Morawski124, Christina M Carlson23, Haeyoon Chang2 and Christopher J Johnson2*
 
* Corresponding author: Christopher J Johnson cjjohnson@usgs.gov
 
Author Affiliations
 
1 Department of Bacteriology, University of Wisconsin, Madison, WI, USA
 
2 USGS National Wildlife Health Center, Madison, WI, USA
 
3 Program in Cellular and Molecular Biology, University of Wisconsin, Madison, WI, USA
 
4 Present address: National Institutes of Health, 9000 Rockville Pike, Bethesda 20892, Maryland, USA
 
For all author emails, please log on.
 
BMC Veterinary Research 2013, 9:157 doi:10.1186/1746-6148-9-157
 
Published: 9 August 2013 Abstract Background Transmissible spongiform encephalopathies (TSEs) affect both domestic sheep (scrapie) and captive and free-ranging cervids (chronic wasting disease; CWD). The geographical range of bighorn sheep (Ovis canadensis; BHS) overlaps with states or provinces that have contained scrapie-positive sheep or goats and areas with present epizootics of CWD in cervids. No TSEs have been documented in BHS, but the susceptibility of this species to TSEs remains unknown.
 
Results We acquired a library of BHS tissues and found no evidence of preexisting TSEs in these animals. The prion protein gene (Prnp) in all BHS in our library was identical to scrapie-susceptible domestic sheep (A136R154Q171 genotype). Using an in vitro prion protein conversion assay, which has been previously used to assess TSE species barriers and, in our study appears to recollect known species barriers in mice, we assessed the potential transmissibility of TSEs to BHS. As expected based upon Prnp genotype, we observed BHS prion protein conversion by classical scrapie agent and evidence for a species barrier between transmissible mink encephalopathy (TME) and BHS. Interestingly, our data suggest that the species barrier of BHS to white-tailed deer or wapiti CWD agents is likely low. We also used protein misfolding cyclic amplification to confirm that CWD, but not TME, can template prion protein misfolding in A136R154Q171 genotype sheep.
 
Conclusions Our results indicate the in vitro conversion assay used in our study does mimic the species barrier of mice to the TSE agents that we tested. Based on Prnp genotype and results from conversion assays, BHS are likely to be susceptible to infection by classical scrapie. Despite mismatches in amino acids thought to modulate prion protein conversion, our data indicate that A136R154Q171 genotype sheep prion protein is misfolded by CWD agent, suggesting that these animals could be susceptible to CWD. Further investigation of TSE transmissibility to BHS, including animal studies, is warranted. The lack of reported TSEs in BHS may be attributable to other host factors or a lack of TSE surveillance in this species.
 
Keywords: Bighorn sheep; Scrapie; Chronic wasting disease; Transmissible mink encephalopathy; Species barrier
 
 
Discussion Using the CER assay, we found evidence that this method recapitulates known species barriers of laboratory mice to TSEs and data to suggest that BHS could be susceptible to classical scrapie and CWD, and less susceptible to TME. Our present investigation and previous studies by others [23,24] suggest that the CER assay can be a valuable addition to other in vitro and in vivo measures of TSE species barriers such as cell-free conversions, PMCA and animal bioassays. Advantages of the CER assay include its low cost, short experimental timeframe and replacement of living animals with tissue samples (which need not be from transgenic mice or perfused). Additionally, the assay does not use radiation, reaction conditions are identical regardless of species or strain of TSE agent and, in our hands, the CER assay is robust and forgiving. Disadvantages of the assay include poor sensitivity compared to PMCA precluding the use of CER as a means to detect PrPTSE, the PrPres product of conversion reactions is not known to be infectious and, importantly, the CER assay is less well-established than other methods of assessing species barriers which makes interpreting reductions in conversion ratios in the absence of other corroborating data difficult. For example, the correlation between a 50% CER and TSE transmission parameters (e.g. disease penetrance, length of incubation period) following experimental challenge remains undefined and further work is needed to characterize this assay for use in species where bioassay data are not available. Nonetheless, in our current study we did find a similar pattern of PrPres formation when either CER or PMCA was used for conversion. Further studies comparing the two techniques is an interesting future direction.
 
We are not aware of any studies examining natural transmission of scrapie from domestic sheep to BHS, but in light of the sequence identity of BHS and domestic A136R154Q171 sheep prion proteins, we must consider scrapie a potential risk to BHS. Efforts to keep domestic sheep and BHS separated, as are prudent to prevent transmission of other pathogens from domestic sheep to BHS [30], are likely warranted around scrapie-infected farms. Further supporting the concept that BHS are at risk for acquiring scrapie is a report of the disease in mouflon (Ovis orientalis), another species of wild sheep [31].
 
In Figure 1, we show the overlap of BHS range with states and provinces known to have had scrapie cases since 2008. Reduced numbers of scrapie outbreaks in recent years, due to disease eradication efforts, may underrepresent the exposure of BHS to scrapie in years prior to 2008. Long-term environmental scrapie contamination may also still be contributing to BHS exposure to disease agent many years after scrapie outbreaks. If incubation periods of scrapie in BHS are greater than five years, exposure of BHS to pre-2008 scrapie flocks may only now have the potential to manifest as disease in BHS. The lack of current evidence for scrapie transmission to BHS could simply be due to insufficient surveillance, but other explanations, such as different susceptibilities by varying routes of exposure between domestic sheep and BHS or BHS being a “dead-end” host for scrapie, should also be explored. Sheep with Prnp genotype V136R154Q171 have been considered to be most -susceptible to classical scrapie and selective breeding efforts have focused on reducing the numbers of these animals in domestic sheep flocks across the U.S. as a scrapie risk reduction measure. Recent research, however, by Gonzalez et al. strongly suggests that Prnp genotype of the recipient sheep is not the sole factor determining its scrapie susceptibility in vivo[32]. In carrying out a series of codon 136 homologous, semi-homologous, and heterologous transmissions of two different natural scrapie isolates into domestic sheep, the study authors conclude that Prnp genotype alone cannot account for the diversity of disease phenotypes observed and that the “scrapie phenotype in sheep results from a complex interaction between source, donor and recipient factors” [32]. The susceptibility of BHS to scrapie is almost certainly dictated by this same interplay. More work is needed to explore the role of scrapie genetics on potential BHS disease transmission, as are analyses of BHS Prnp genetics using more geographically disparate samples.
 
The finding that white-tailed deer CWD agent could convert sheep PrPC to PrPres in either CER assays (Figure 6) or PMCA (Additional file 2) was notable given the sequence variations found between BHS or domestic sheep and white-tailed deer prion proteins (Figure 2), including serine to asparagine and asparagine to threonine changes in the “rigid loop” portion of the protein thought to control species susceptibility to CWD [33,34]. By CER assay, we similarly found conversion of BHS PrPC by wapiti CWD heterozygous methionine/leucine at position 132. In wapiti, animals heterozygous or homozygous for leucine at prion protein amino acid 132 (L132) have a lengthened CWD incubation period [35] and L132 appears to limit CWD, but not classical scrapie, susceptibility in a transgenic mouse model [36]. Despite these amino acid mismatches, including those in the “rigid loop”, the CWD agents were still effective at misfolding PrPC from BHS. In previous studies, we have also found that voles, which have mismatches in the “rigid loop” portion of the protein, are susceptible PrP misfolding and infection by cervid CWD [37,38].
 
Previous work on the species barrier of sheep to CWD has been equivocal. Using cell-free conversion assays, Raymond et al. found that A136Q171 domestic sheep PrPC was not especially-well converted by CWD agent, but was the non-cervid substrate, among six tested species, that yielded the most PrPres[21]. In an animal study, Hamir et al. intracerebrally challenged eight domestic sheep of various Prnp genotypes with mule deer CWD [39]. One clinically-positive (heterozygous A/V136R154Q171) and one preclinical sheep (homozygous A136R154Q171) were identified at the conclusion of the study, indicating that sheep can be infected by CWD, although transmission is not especially facile.
 
The results of our conversion assays appear to be supported by in vivo work by Béringue et al. which indicate that V136R154Q171 ovinized transgenic mice challenged with wapiti CWD harbor high levels of splenic PrPres, indicating that sheep PrPC is susceptible to misfolding by CWD agent [40]. At least one group has failed to observe clinical TSE signs in BHS when they were housed with a facility with CWD-infected animals [7]. Our results in combination with those of Béringue et al., suggest that the lack of CWD transmission to BHS was not due to inability of BHS PrPC to be misfolded by CWD agent, but must derive from other factors.
 
In our investigation, we used white-tailed deer and wapiti CWD, but have not yet investigated BHS prion protein conversion by mule deer CWD. Given the sequence similarity among cervid Prnp genes and our evidence that white-tailed deer and wapiti CWD can convert BHS PrPC to PrPres, we expect CWD from the various species to behave similarly. In a previous report, Li et al. found less PrPres generation in domestic sheep substrates when templated by wapiti CWD [23] than we found for BHS in our study. The genotype of the domestic sheep substrate in the previous study is unclear and differences between the sheep prion protein sequences or other species-specific differences could explain the limited conversion that they observed. Alternatively, differences in the genotypes of the wapiti CWD isolates used in the two studies could also explain variations in PrPres levels in sheep substrates.
 
Conclusion The results from our study suggest that the CER assay has the potential to be a useful tool to screen TSE species barriers. Further comparisons with PMCA and bioassays will clarify the best uses of the assay and help to define CER that are < 100%. We found that BHS are unlikely to have resistance to domestic sheep classical scrapie due to their Prnp genotype. Our conversion reactions suggest that the species barrier protecting BHS from CWD may not be large and further studies, including in vivo experiments, are warranted. These animal challenge studies need not necessarily be performed in BHS, but could rather use Prnp genotype A136R154Q171 domestic sheep or existing transgenic mouse models [41]. Additionally, investigation into the susceptibility of BHS to atypical forms of scrapie is also an interesting future direction.
 
 
 
 
 
Deadly Diseases Could Strike Bighorn Sheep
 
Released: 8/28/2013 1:18:09 PM
 
Contact Information: U.S. Department of the Interior, U.S. Geological Survey Office of Communications and Publishing 12201 Sunrise Valley Dr, MS 119 Reston, VA 20192 Gail Moede Rogall 1-click interview Phone: 608-270-2438
 
Marisa Lubeck 1-click interview Phone: 303-202-4765
 
 Declining bighorn sheep populations may be vulnerable to some of the fatal diseases, including chronic wasting disease (CWD), that are found in their western U.S. habitats, according to a new U.S. Geological Survey study.
 
USGS National Wildlife Health Center (NWHC) research showed that bighorn sheep are likely susceptible to the deadly neurological diseases scrapie and CWD, which are occurring in or near natural bighorn sheep environments. These fatal diseases are caused by mysterious proteins called prions, and are known to infect domestic sheep (scrapie) and non-domestic deer, elk, and moose (CWD). The USGS study is published in the journal BMC Veterinary Research, and is available online.
 
"Bighorn sheep are economically and culturally important to the western U.S.," said Dr. Christopher Johnson, USGS scientist and senior author of the report. "Understanding future risks to the health of bighorn sheep is key to proper management of the species."
 
USGS laboratory tests found evidence that bighorn sheep could be vulnerable to CWD from either white-tailed deer or elk, and to a domestic sheep prion disease known as scrapie. However, none of a small number of bighorn sheep sampled in the study showed evidence of infection.
 
"Our results do not mean that bighorns get, or will eventually get, prion diseases," Johnson said. "However, wildlife species like bighorn sheep are increasingly exposed to areas where CWD occurs as the disease expands to new geographical areas and increases in prevalence."
 
The laboratory test results could be useful to wildlife managers because bighorn sheep habitats overlap with farms and ranches with scrapie-infected sheep and regions where CWD is common in deer, elk, and moose.
 
Bighorn sheep populations in western North America have declined from habitat loss and, more recently, epidemics of fatal pneumonia thought to be transmitted to them from domestic sheep. Prion diseases are another possible threat to this valuable species.
 
For more information on prion diseases such as CWD, please visit the USGS NWHC website.
 
 
 
 
 
Friday, July 26, 2013
 
Voluntary Scrapie Program USA UPDATE July 26, 2013 increase in FY 2013 is not statistically meaningful due to the sample size
 
 
 
 
Thursday, March 29, 2012
 
atypical Nor-98 Scrapie has spread from coast to coast in the USA 2012
 
NIAA Annual Conference April 11-14, 2011San Antonio, Texas
 
 
 
 
Wednesday, February 16, 2011
 
IN CONFIDENCE
 
SCRAPIE TRANSMISSION TO CHIMPANZEES
 
IN CONFIDENCE
 
 
 
 
Sunday, December 12, 2010
 
EFSA reviews BSE/TSE infectivity in small ruminant tissues News Story 2 December 2010
 
 
 
 
Sunday, April 18, 2010
 
SCRAPIE AND ATYPICAL SCRAPIE TRANSMISSION STUDIES A REVIEW 2010
 
 
 
 
Saturday, July 6, 2013
 
Small Ruminant Nor98 Prions Share Biochemical Features with Human Gerstmann-Sträussler-Scheinker Disease and Variably Protease-Sensitive Prionopathy
 
Research Article
 
 
 
 
Thursday, August 15, 2013
 
The emergence of novel BSE prions by serial passages of H-type BSE in bovinized mice
 
 
 
 
snip...
 
 
Stability comparison of BSE to other cattle-passaged TSEs
 
In addition to comparing the different BSE strains, we also used the stability assay to characterize the biochemical properties of other TSEs passaged into cattle. Scrapie and CWD are both transmissible into cattle by IC inoculation, leading to PrPSc accumulation--but not significant spongiform changes--in the brain [29,30]. Transmissible mink encephalopathy has been hypothesized to have originated from the feeding of downer cattle, possibly carrying atypical, L-type BSE, to farm-raised mink [37]. We wanted to determine if the profiles of PrPSc from these TSEs passaged in cattle brain were distinguishable from each other or from other BSE strains, with potential implications for understanding strain origins and/or improving (non-BSE) TSE diagnosis in cattle.
 
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Keywords
 
Bovine spongiform encephalopathy, BSE, ELISA, Prion, PrP, Scrapie, Stability, Transmissible spongiform encephalopathy, TSE
 
ISSN 1746-6148 Article type Research article Submission date 12 April 2013 Acceptance date 12 August 2013 Publication date 15 August 2013 Article URL http://www.biomedcentral.com/1746-6148/9/167 Like all articles in BMC journals, this peer-reviewed article can be downloaded, printed and distributed freely for any purposes (see copyright notice below). Articles in BMC journals are listed in PubMed and archived at PubMed Central. For information about publishing your research in BMC journals or any BioMed Central journal, go to http://www.biomedcentral.com/info/
 
 
 
 
snip...see full text and more here ;
 
 
 
Thursday, August 15, 2013
 
Stability properties of PrPSc from cattle with experimental transmissible spongiform encephalopathies: use of a rapid whole homogenate, protease-free assay
 
 
 
 
Sunday, July 21, 2013
 
Welsh Government and Food Standards Agency Wales Joint Public Consultation on the Proposed Transmissible Spongiform Encephalopathies (Wales) Regulations 2013 Singeltary Submission WG18417
 
 
 
 
 
 
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Monday, August 26, 2013

The Presence of Disease-Associated Prion Protein in Skeletal Muscle of Cattle Infected with Classical Bovine Spongiform Encephalopathy

Journal of Veterinary Medical Science Article ID: 13-0363 Language: English Japanese Previous Article |Next Article http://dx.doi.org/10.1292/jvms.13-0363 DN/JST.JSTAGE/jvms/13-0363

 

Advance Publication

 

 

The Presence of Disease-Associated Prion Protein in Skeletal Muscle of Cattle Infected with Classical Bovine Spongiform Encephalopathy

 

 

Hiroyuki OKADA1), Kohtaro MIYAZAWA1), Shigeo FUKUDA2), Yoshifumi IWAMARU1), Morikazu IMAMURA1), Kentaro MASUJIN1), Yuichi MATSUURA1), Takashi FUJII2), Kei FUJII2), Soichi KAGEYAMA2), Miyako YOSHIOKA1), Yuichi MURAYAMA1), Takashi YOKOYAMA1)

 

1) National Institute of Animal Health, National Agriculture and Food Research Organization 2) Hokkaido Animal Research Center, Hokkaido Research Organization

 

 [Advance Publication] Released 2013/08/27 received 2013/07/16 accepted 2013/08/13 Keywords: BSE, muscle spindle, prion, skeletal muscle

 

Full Text PDF [832K]

 

Abstracts

 

The aim of this study was to investigate the presence of disease-associated prion protein (PrPSc) in the skeletal muscle of cattle infected with classical bovine spongiform encephalopathy (C-BSE). The study was carried out systematically in 12 different muscle samples from 43 (3 field and 40 experimental) cases of C-BSE; however, muscle spindles were not available in many of these cases. Therefore, analysis became restricted to a total of 31 muscles in 23 cattle. Even after this restriction, low levels of PrPSc were detected in the muscle spindles of the masseter, intercostal, triceps brachii, psoas major, quadriceps femoris and semitendinosus muscles from 3 field and 6 experimental clinical-stage cases. The present data indicate that small amounts of PrPSc are detectable by immunohistochemistry in the skeletal muscles of animals terminally affected with C-BSE.

 

 

 


 

 

full text pdf here ;

 

 


 

 

 

Monday, March 19, 2012

 

Infectivity in Skeletal Muscle of Cattle with Atypical Bovine Spongiform Encephalopathy PLoS One. 2012; 7(2): e31449.

 


 

 

 

***Infectivity in skeletal muscle of BASE-infected cattle

 


 

 

 

Wednesday, May 2, 2012

 

ARS FLIP FLOPS ON SRM REMOVAL FOR ATYPICAL L-TYPE BASE BSE RISK HUMAN AND ANIMAL HEALTH

 


 

 

 

Tuesday, March 5, 2013
 
Use of Materials Derived From Cattle in Human Food and Cosmetics; Reopening of the Comment Period FDA-2004-N-0188-0051 (TSS SUBMISSION)
 
FDA believes current regulation protects the public from BSE but reopens comment period due to new studies
 
 
 
 
Sunday, July 21, 2013
 
Biochemical Characteristics and PrPSc Distribution Pattern in the Brains of Cattle Experimentally Challenged with H-type and L-type Atypical BSE
 
 
 
 

Thursday, August 15, 2013

 

Stability properties of PrPSc from cattle with experimental transmissible spongiform encephalopathies: use of a rapid whole homogenate, protease-free assay

 


 

 

 

Thursday, August 15, 2013

 

The emergence of novel BSE prions by serial passages of H-type BSE in bovinized mice

 


 

 

Envt.07:

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

Martin L. Daus,1,† Johanna Breyer,2 Katjs Wagenfuehr,1 Wiebke Wemheuer,2 Achim Thomzig,1 Walter Schulz-Schaeffer2 and Michael Beekes1 1Robert Koch Institut; P24 TSE; Berlin, Germany; 2Department of Neuropathology, Prion and Dementia Research Unit, University Medical Center Göttingen; Göttingen, Germany †Presenting author; Email: dausm@rki.de

Chronic wasting disease (CWD) is a contagious, rapidly spreading transmissible spongiform encephalopathy (TSE) occurring in cervids in North America. Despite efficient horizontal transmission of CWD among cervids natural transmission of the disease to other species has not yet been observed. Here, we report a direct biochemical demonstration of pathological prion protein PrPTSE and of PrPTSE-associated seeding activity in skeletal muscles of CWD-infected cervids. The presence of PrPTSE was detected by Western- and postfixed frozen tissue blotting, while the seeding activity of PrPTSE was revealed by protein misfolding cyclic amplification (PMCA). The concentration of PrPTSE in skeletal muscles of CWD-infected WTD was estimated to be approximately 2000- to 10000-fold lower than in brain tissue. Tissue-blot-analyses revealed that PrPTSE was located in muscle- associated nerve fascicles but not, in detectable amounts, in myocytes. 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.

http://www.landesbioscience.com/journals/prion/Prion5-Supp-PrionEnvironment.pdf?nocache=1333529975



Wednesday, April 06, 2011

 

Presence and Seeding Activity of Pathological Prion Protein (PrPTSE) in Skeletal Muscles of White-Tailed Deer Infected with Chronic Wasting Disease

 


 

 

 

Sunday, November 21, 2010

 

Preclinical Deposition of Pathological Prion Protein in Muscle of Experimentally Infected Primates and potential Iatrogenic TSE there from Preclinical Deposition of Pathological Prion Protein in Muscle of Experimentally Infected Primates

 


 

 

 


EMBO reports AOP Published online: 11 April 2003



Widespread PrPSc accumulation in muscles of hamsters orally infected with scrapie



Achim Thomzig, Christine Kratzel, Gudrun Lenz, Dominique KrÒ¼ger & Michael Beekes Robert Koch-Institut, P26, Nordufer 20, D-13353 Berlin, Germany

Received 13 February 2003; Accepted 13 March 2003; Published online 11 April 2003.

Abstract :

Scrapie, bovine spongiform encephalopathy and chronic wasting disease are orally communicable, transmissible spongiform encephalopathies (TSEs). As zoonotic transmissions of TSE agents may pose a risk to human health, the identification of reservoirs for infectivity in animal tissues and their exclusion from human consumption has become a matter of great importance for consumer protection. In this study, a variety of muscles from hamsters that were orally challenged with scrapie was screened for the presence of a molecular marker for TSE infection, PrPSc (the pathological isoform of the prion protein PrP). Sensitive western blotting revealed consistent PrPSc accumulation in skeletal muscles from forelimb and hindlimb, head, back and shoulder, and in tongue. Previously, our animal model has provided substantial baseline information about the peripheral routing of infection in naturally occurring and orally acquired ruminant TSEs. Therefore, the findings described here highlight further the necessity to investigate thoroughly whether muscles of TSE-infected sheep, cattle, elk and deer contain infectious agents.


http://www.emboreports.org/

 

snip...see;

 

 

Monday, June 22, 2009

 

PrPTSE in muscle-associated lymphatic tissue during the preclinical stage of mice orally-infected with BSE

 


 

 

 

 

Friday, December 05, 2008

 

Detection of Prion Infectivity in Fat Tissues of Scrapie-Infected Mice

 


 

 

 

Sunday, August 11, 2013

 

Creutzfeldt-Jakob Disease CJD cases rising North America updated report August 2013

 

Creutzfeldt-Jakob Disease CJD cases rising North America with Canada seeing an extreme increase of 48% between 2008 and 2010

 


 

 

 

 

Sunday, July 21, 2013

 

Welsh Government and Food Standards Agency Wales Joint Public Consultation on the Proposed Transmissible Spongiform Encephalopathies (Wales) Regulations 2013 Singeltary Submission WG18417

 


 

 

 

 

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