Prionics works with the European Community Reference Laboratory for TSEs in the U.K. to launch the VLA Discriminatory Western Blot, a diagnostic kit to distinguish between BSE and scrapie in sheep and goats (small ruminants).
The Veterinary Laboratories Agency (VLA) in the U.K. - the European Community Reference Laboratory for TSEs - has had close research links with the founders of Prionics AG, long since before the Swiss company was formed. Early collaborations have appeared in publications, specifically targeting the validation of diagnostic tests for BSE and scrapie. Now the VLA has launched a new diagnostic kit to help distinguish between these two diseases in small ruminants. The test is based on the Prionics®-Check WESTERN, a routine test used worldwide for BSE and scrapie diagnostics. Prionics, VLA and R-Biopharm have come together to compile the new discriminatory test - the VLA Discriminatory Western Blot.
Differentiation between BSE and scrapie in small ruminants
The VLA Discriminatory Western Blot delivers results like the Prionics®-Check WESTERN, by taking a fingerprint of the disease-specific prion protein (PrPSc). Additionally, the differential staining characteristics with the two monoclonal antibodies (mAb) 6H4 and P4 also provides specific information on the nature of the prion strain. Unlike mAb P4 (R-Biopharm, AG, Darmstadt, Germany) which preferentially recognizes natural scrapie samples [Figure B], the Prionics mAb 6H4 recognizes PrPSc in all samples [Figure A].
Human risk
The origin of BSE has not been clearly defined, but the most widely accepted theorie about its origin is through the rendering of scrapie infected sheep with the resultant meat and bone meal (MBM) being fed back to growing cattle. It is considered likely that sheep and goats were then fed the same contaminated MBM, inadvertently infecting them with BSE. Until recently, when a confirmed case of naturally occurring BSE in a French goat was announced, only experimental research had supported this claim.
The potential concern that small ruminants can be carriers of BSE has created a heightened awareness about a new source of contamination to humans. It is not possible to differentiate by clinical signs between experimental BSE in sheep and natural scrapie cases and, until recently, the search for BSE in sheep has only been possible with time consuming and expensive experiments involving mouse bioassays.
