Figure 3. Brain atypical proteinase K–resistant prion protein (PrPres) of porcine PrP transgenic mice infected with an atypical scrapie (SC-PS152) agent (lane 4) versus sheep bovine spongiform encephalopathy (Sheep-BSE) agent (lane 2). Electrophoretic profiles and antibody labeling of PrPres detected with monoclonal antibodies Sha31 (A) or 12B2 (B). Profiles produced by atypical scrapie (SCPS152) (lane 3) and sheep-BSE (lane 1) before passage in the porcine mouse model are shown for comparison. MW, molecular mass in kilodaltons. C) Triangular plot of the glycosyl fractions of PrPres after proteinase K digestion and Western blotting using the Sha31 antibody. Data shown are the means of >5 measurements obtained from density scans in >2 Western blots. To interpret the plot, read the values for the diglycosyl, monoglycosyl, and aglycosyl fractions along the bottom, right and left axes of the triangle, respectively. For each point, the sum of the 3 values is 100.