MOLECULAR ANALYSIS OF BOVINE SPONGIFORM ENCEPHALOPATHY AND SCRAPIE STRAIN VARIATION

Five mouse scrapie strains, a mouse-passaged scrapie isolate derived f rom a field case in sheep in Germany, and 2 mouse-passaged bovine spon giform encephalopathy (BSE) isolates were analyzed by immunoblot in re gards to banding patterns of proteinase K-digested pathologic prion pr oteins (PrPres). To obtain reliable results, the photo-imager techniqu e was used for measurement of staining band intensities. Distinct and reproducible profiles were observed for the different strains or isola tes. A British and a German BSE isolate were similar, suggesting the s ame source of infection. The German scrapie isolate resembled scrapie strain ME7, which has frequently been isolated from sheep scrapie in t he past. In selected strains or isolates, no influence of the mouse li nes used was observed on PrPres profiles, nor were brain region-specif ic differences apparent. This investigation suggests that PrPres glyco typing can be an invaluable tool for the in vitro differentiation of B SE and scrapie isolates.