Prion Infectivity in Fat of Deer with Chronic Wasting Disease▿

Brent Race#, Kimberly Meade-White#, Richard Race and Bruce Chesebro* + Author Affiliations

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.

http://jvi.asm.org/content/83/18/9608.full

Prions in Skeletal Muscles of Deer with Chronic Wasting Disease

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.

http://science.sciencemag.org/content/311/5764/1117.long

CDC

May 2009

Research

Chronic Wasting Disease Prions in Elk Antler Velvet

https://wwwnc.cdc.gov/eid/article/15/5/08-1458_article

Cervid to human prion transmission 5R01NS088604-04 Update

National Institute of Health (NIH)

http://grantome.com/grant/NIH/R01-NS088604-04

cwd scrapie pigs oral routes

***> However, at 51 months of incubation or greater, 5 animals were positive by one or more diagnostic methods. Furthermore, positive bioassay results were obtained from all inoculated groups (oral and intracranial; market weight and end of study) suggesting that swine are potential hosts for the agent of scrapie. <***

>*** Although the current U.S. feed ban is based on keeping tissues from TSE infected cattle from contaminating animal feed, swine rations in the U.S. could contain animal derived components including materials from scrapie infected sheep and goats. These results indicating the susceptibility of pigs to sheep scrapie, coupled with the limitations of the current feed ban, indicates that a revision of the feed ban may be necessary to protect swine production and potentially human health. <***

***> 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 month group was positive by EIA. PrPSc was detected by QuIC in at least one of the lymphoid tissues examined in 5/6 pigs in the intracranial <6 months group, 6/7 intracranial >6 months group, 5/6 pigs in the oral <6 months group, and 4/6 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=353091

https://www.ars.usda.gov/research/project/?accnNo=432011&fy=2017

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

Early preclinical detection of prions in the skin of prion-infected animals

Zerui Wang1,2, Matteo Manca3, Aaron Foutz4, Manuel V. Camacho1 , Gregory J. Raymond3, Brent Race3, Christina D. Orru3, Jue Yuan1 , Pingping Shen1,2, Baiya Li1,5, Yue Lang1,2, Johnny Dang1 , Alise Adornato1 , Katie Williams3, Nicholas R. Maurer1 , Pierluigi Gambetti1 , Bin Xu6, Witold Surewicz7, Robert B. Petersen1,8, Xiaoping Dong9, Brian S. Appleby1,4,10, Byron Caughey 3, Li Cui2, Qingzhong Kong1,4,10,11 & Wen-Quan Zou1,2,4,9,10,11

snip...

Although the reasons for early and widespread presence of PrPSc in the skin remain unclear, possibilities include the spread of the prion inoculum itself, or endogenously replicating prions, from the brain through the peripheral nerves to the skin within the 2–3 weeks required for the first detection by our ultrasensitive
sPMCA and RT-QuIC assays. PrP seeding activity has been detected in the blood in the prion-infected hamsters and deer immediately after peripheral inoculation including oral, nasal, or blood route30. However, no reports have shown that PrPSc is consistently detectable in the blood of prion-infected hamsters within 2 weeks post intracerebral inoculation. Thus, the early spread of PrPSc from the brain-to-the skin in the intracerebrally 263K-inoculated hamsters is likely either not through the blood or, if initially from the blood, requires time-dependent concentration or replication in the skin to become detectable.

snip...

Skin PrPSc may derive from urine or fecal prion contamination in addition to possible skin shedding due to scratching or biting each other. Indeed, scrapie infectivity was reported in the urine of prion-infected mice coincident with lymphocytic nephritis during their preclinical and clinical stages of prion infection35,36. It was also observed in their urine in intracerebrally inoculated hamsters even without any apparent inflammation21. In addition, deer with clinical CWD and mild to moderate nephritis were found to have sPMCA-detectable PrPSc and CWD-infectivity in urine22. Using sPMCA, PrPSc was detected in urine of ~80% of the hamsters intraperitoneally inoculated with 263K prions at the symptomatic stage23. Notably, PrPSc was detected in urine, but only at the terminal stage of disease in intracerebrally inoculated hamsters, except for a few days immediately after oral administration24. Similar to the observations by Gonzalez-Romero et al.23, Murayama et al. also found that not all infected hamsters had detectable urine PrPSc even at the terminal stage24. The skin PrPSc detected early in the intracerebrally infected hamsters, but not in the co-habitated-negative controls, at 2 wpi suggests that skin prions may not result from urine at the early stage of infection.

https://www.nature.com/articles/s41467-018-08130-9.pdf

https://prionprp.blogspot.com/2019/01/early-preclinical-detection-of-prions.html


Terry S. Singeltary Sr.

Mice fat? Really?


India eats 5x more goat and sheep then the US, they also naturally have higher scrapie hits.
Yet India has a major difference in Alzheimer’s and dementia vs the US, in fact Alzheimer’s is Extremely rare in India..

Just another reason to build a wall...

Wrong, check the outdoor annual page