Sheep Are Susceptible to the Bovine Adapted Transmissible Mink Encephalopathy agent by Intracranial Inoculation and Have Evidence of Infectivity in Lymphoid Tissues
Sheep Are Susceptible to the Bovine Adapted Transmissible Mink Encephalopathy agent by Intracranial Inoculation and Have Evidence of Infectivity in Lymphoid Tissues
Eric D. Cassmann
Jodi D. Smith
Justin J. Greenlee- 1National Animal Disease Center (USDA ARS), United States
- 2Oak Ridge Institute for Science and Education (ORISE), United States
- 3College of Veterinary Medicine, Iowa State University, United States
Transmissible mink encephalopathy (TME) is a food borne prion disease. Epidemiological and experimental evidence suggests similarities between the agents of TME and L-BSE. This experiment demonstrates the susceptibility of four different genotypes of sheep to the bovine adapted TME agent by intracranial inoculation. The four genotypes of sheep used in this experiment had polymorphisms corresponding to codons 136, 154, and 171 of the prion gene: V136R154Q171/VRQ, VRQ/ARQ, ARQ/ARQ, and ARQ/ARR. All intracranially inoculated sheep without comorbidities (15/15) developed clinical signs and had detectable PrPSc by immunohistochemistry, western blot, and enzyme immunoassay (EIA). The mean incubation periods in sheep with bovine adapted TME correlated with their relative genotypic susceptibility. There was peripheral distribution of PrPSc in the trigeminal ganglion and neuromuscular spindles; however, unlike classical scrapie and C-BSE in sheep, sheep inoculated with the bovine TME agent did not have immunohistochemically detectable PrPSc in the lymphoid tissue. To rule out the presence of infectivity, the lymph nodes of two sheep genotypes, VRQ/VRQ and ARQ/ARQ, were bioassayed in transgenic mice expressing ovine prion protein. Mice intracranially inoculated with retropharyngeal lymph node from a VRQ/VRQ sheep were EIA positive (3/17) indicating that sheep inoculated with the bovine TME agent harbor infectivity in their lymph nodes despite a lack of detection with conventional immunoassays. Western blot analysis demonstrated similarities in the migration patterns between bovine TME in sheep, the bovine adapted TME inoculum, and L-BSE. Overall, these results demonstrate that sheep are susceptible to the bovine adapted TME agent, and the tissue distribution of PrPSc in sheep with bovine TME is distinct from classical scrapie.
Keywords: Prion Disease, prion protein, PRNP, PrPSc = abnormal form of PrP, Sheep - Diseases, Transmissible mink encephalopathy (TME), Transmissible spongiform encephalopathies (TSE)
Received: 18 Jul 2019; Accepted: 14 Nov 2019.
Copyright: © 2019 Cassmann, Moore, Smith and Greenlee. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Dr. Justin J. Greenlee, National Animal Disease Center (USDA ARS), Ames, 50010, Iowa, United States, Justin.greenlee@ars.usda.gov
''To rule out the presence of infectivity, the lymph nodes of two sheep genotypes, VRQ/VRQ and ARQ/ARQ, were bioassayed in transgenic mice expressing ovine prion protein.''
''Mice intracranially inoculated with retropharyngeal lymph node from a VRQ/VRQ sheep were EIA positive (3/17) indicating that sheep inoculated with the bovine TME agent harbor infectivity in their lymph nodes despite a lack of detection with conventional immunoassays.''
***> ''indicating that sheep inoculated with the bovine TME agent harbor infectivity in their lymph nodes despite a lack of detection with conventional immunoassays.''
WEDNESDAY, NOVEMBER 20, 2019
Review: Update on Classical and Atypical Scrapie in Sheep and Goats
WEDNESDAY, NOVEMBER 20, 2019
Wyoming Game and Fish Department Chronic Wasting Disease Collaborative Process Interim Report OCTOBER 2019
THURSDAY, AUGUST 08, 2019
Raccoons accumulate PrPSc after intracranial inoculation with the agents of chronic wasting disease (CWD) or transmissible mink encephalopathy (TME) but not atypical scrapie
WEDNESDAY, OCTOBER 16, 2019
Australia Assessment of bulk wheat from Canada Part B: Animal biosecurity risk advice, CWD TSE Prion concerns are mounting
Colorado Chronic Wasting Disease Response Plan December 2018
I. Executive Summary Mule deer, white-tailed deer, elk and moose are highly valued species in North America. Some of Colorado’s herds of these species are increasingly becoming infected with chronic wasting disease (CWD). As of July 2018, at least 31 of Colorado's 54 deer herds (57%), 16 of 43 elk herds (37%), and 2 of 9 moose herds (22%) are known to be infected with CWD. Four of Colorado's 5 largest deer herds and 2 of the state’s 5 largest elk herds are infected. Deer herds tend to be more heavily infected than elk and moose herds living in the same geographic area. Not only are the number of infected herds increasing, the past 15 years of disease trends generally show an increase in the proportion of infected animals within herds as well. Of most concern, greater than a 10-fold increase in CWD prevalence has been estimated in some mule deer herds since the early 2000s; CWD is now adversely affecting the performance of these herds.
snip...
(the map on page 71, cwd marked in red, is shocking...tss)
ORIGIN OF CHRONIC WASTING DISEASE TSE PRION?
COLORADO THE ORIGIN OF CHRONIC WASTING DISEASE CWD TSE PRION?
*** Spraker suggested an interesting explanation for the occurrence of CWD. The deer pens at the Foot Hills Campus were built some 30-40 years ago by a Dr. Bob Davis. At or abut that time, allegedly, some scrapie work was conducted at this site. When deer were introduced to the pens they occupied ground that had previously been occupied by sheep.
IN CONFIDENCE, REPORT OF AN UNCONVENTIONAL SLOW VIRUS DISEASE IN ANIMALS IN THE USA 1989
ALSO, one of the most, if not the most top TSE Prion God in Science today is Professor Adriano Aguzzi, and he recently commented on just this, on a cwd post on my facebook page August 20 at 1:44pm, quote;
''it pains me to no end to even contemplate the possibility, but it seems entirely plausible that CWD originated from scientist-made spread of scrapie from sheep to deer in the colorado research facility. If true, a terrible burden for those involved.'' August 20 at 1:44pm ...end
”The occurrence of CWD must be viewed against the contest of the locations in which it occurred. It was an incidental and unwelcome complication of the respective wildlife research programmes. Despite it’s subsequent recognition as a new disease of cervids, therefore justifying direct investigation, no specific research funding was forthcoming. The USDA viewed it as a wildlife problem and consequently not their province!” page 26.
TUESDAY, OCTOBER 29, 2019
America BSE 589.2001 FEED REGULATIONS, BSE SURVEILLANCE, BSE TESTING, and CJD TSE Prion
WEDNESDAY, JULY 31, 2019
The agent of transmissible mink encephalopathy passaged in sheep is similar to BSE-L
49. The agent of transmissible mink encephalopathy passaged in sheep is similar to BSE-L
E. D. Cassmanna,b, S. J. Moorea,b, R. D. Kokemullera, A. Balkema-Buschmannc, M. H. Groschupcand J. J. Greenleea
aVirus and Prion Research Unit, National Animal Disease Center, ARS, United States Department of Agriculture, Ames, IA, USA (EDC, SJM, RDK, JJG); bOak Ridge Institute for Science and Education (ORISE) through an interagency agreement between the U.S. Department of Energy (DOE) and the U.S. Department of Agriculture (USDA). ORISE is managed by ORAU under DOE contract number DE-SC0014664. (EDC, SJM), Department of Veterinary Pathology, Iowa State University, Ames, IA, USA (JDS); cInstitute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Greifswald – Isle of Riems, Germany (ABB, MHG)
CONTACT E. D. Cassmann eric.cassmann@usda.gov
ABSTRACT
Introduction: Transmissible mink encephalopathy (TME) is a fatal neurologic prion disease of farmed mink. Epidemiologic and experimental evidence following a Wisconsin outbreak in 1985 has linked TME to low-type bovine spongiform encephalopathy (BSE-L). Evidence suggests that farmed mink were likely exposed through feeding of BSE-L infected downer cattle. The interspecies transmission of TME to cattle has been documented. Recently, we demonstrated the susceptibility of sheep to cattle passaged TME by intracranial inoculation. The aim of the present study was to compare ovine passaged cattle TME to other prion diseases of food-producing animals. Using a bovine transgenic mouse model, we compared the disease phenotype of sheep TME to BSE-C and BSE-L.
Materials and Methods: Separate inoculants of sheep passaged TME were derived from animals with the VRQ/VRQ (VV136) and ARQ/VRQ (AV136) prion protein genotype. Transgenic bovinized mice (TgBovXV) were intracranially inoculated with 20 µl of 1% w/v brain homogenate. The disease phenotypes were characterized by comparing the attack rates, incubation periods, and vacuolation profiles in TgBovXV mice.
Results: The attack rate for BSE-C (13/13), BSE-L (18/18), and TMEVV (21/21) was 100%; whereas, the TMEAV group (15/19) had an incomplete attack rate. The average incubation periods were 299, 280, 310, and 541 days, respectively. The vacuolation profiles of BSE-L and TMEVV were most similar with mild differences observed in the thalamus and medulla. Vacuolation profiles from the BSE-C and TMEAV experimental groups were different than TMEVVand BSE-L.
Conclusion: Overall the phenotype of disease in TME inoculated transgenic mice was dependent on the sheep donor genotype (VV vs AV). The results of the present study indicate that TME isolated from VRQ/VRQ sheep is similar to BSE-L with regards to incubation period, attack rate, and vacuolation profile. Our findings are in agreement with previous research that found phenotypic similarities between BSE-L and cattle passaged TME in an ovine transgenic rodent model. In this study, the similarities between ovine TME and BSE-L are maintained after multiple interspecies passages.
Prion2019 Conference
2007
August 1988
Evidence That Transmissible Mink Encephalopathy Results From Feeding Infected Cattle
Evidence That Transmissible Mink Encephalopathy Results from Feeding Infected Cattle Over the next 8-10 weeks, approximately 40% of all the adult mink on the farm died from TME. snip... The rancher was a ''dead stock'' feeder using mostly (>95%) downer or dead dairy cattle...
WEDNESDAY, JULY 31, 2019
The agent of transmissible mink encephalopathy passaged in sheep is similar to BSE-L
Terry S. Singeltary Sr.
posted by Terry S. Singeltary Sr. at
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