INRA scientists have shown for the first time that the pathogens responsible for scrapie in small ruminants (prions) have the potential to convert the human prion protein from a healthy state to a pathological state.
In mice models reproducing the human species barrier, this prion induces a disease similar to Creutzfeldt-Jakob disease. These primary results published in Nature Communications on 16 December 2014, stress the necessity to reassess the transmission of this disease to humans.
Scrapie is a neurodegenerative disease that has been known for centuries and which affects sheep and goats. Similar to Bovine Spongiform Encephalopathy (BSE) or mad cow disease, scrapie is caused by a transmissible pathogen protein called prion.
However, and contrary to BSE1, epidemiological studies have never been able to establish a link between this disease and the occurrence of prion diseases in humans. “Risks of transmitting scrapie to humans (zoonose) were hitherto considered negligible because of the species barrier that naturally prevents prion propagation between species”, said Olivier Andreoletti, INRA scientist who led the present study.
Researchers at INRA studied the permeability of the human transmission barrier to pathogens responsible for scrapie, using animal models specifically developed for this purpose. This approach previously allowed the confirmation of the zoonotic nature of prions responsible for BSE in cows and of the variant of Creutzfeldt-Jakob disease in humans (vCJD).
Unexpectedly, in these rodent models, certain pathogens responsible for scrapie were able to cross the transmission barrier. Moreover, the pathogens that propagated through this barrier were indistinguishable from the prions causing the sporadic form of Creutzfeldt-Jakob disease (sCJD). This data suggest a potential link between the occurrence of certain sCJD and these animal prions.
“Since CJD is scarce, about 1 case per million and per year, and incubation periods are usually long -several decades- it is extremely difficult for epidemiological studies to try and make this link”, explains Olivier Andreoletti.
Read more: Scrapie could breach the species barrier
The Latest on: Scrapie
via Google News
The Latest on: Scrapie
- Experimental Treatment Slows Prion Diseaseon October 3, 2019 at 5:00 pm
Scientists using an experimental treatment have slowed the progression of scrapie, a degenerative central nervous disease caused by prions, in laboratory mice and greatly extended the rodents’ lives, ...
- USDA changes sheep, goat scrapie ID requirementson August 21, 2019 at 11:58 pm
“USDA-APHIS’s National Scrapie Eradication Program has made great strides toward disease freedom since its inception in 2002, largely as a result of effective slaughter surveillance,” said Dr. Barry ...
- Prion disease in mice treated successfully with antisense oligonucleotideson August 1, 2019 at 7:52 pm
Prion proteins are known to cause scrapie – a neurodegenerative condition. It is capable of debilitating damage to the nervous system. Researchers have successfully devised a treatment for this ...
- Scrapie, a disease related to mad cow, found in two flocks of sheep in Albertaon July 18, 2019 at 6:38 pm
The Canadian Food Inspection Agency says some sheep in Alberta have been infected with scrapie, a fatal disease that affects the animals' nervous system. The federal agency's website says classic ...
via Bing News