Figure 1.

Brain PrP^res in bovine PrP transgenic mice infected with BSE-L or BSE agents. A Western blot analysis of proteinase K-digested brain homogenates from diseased mice is presented. A, The distinct PrP^res profiles of BSE H-type, BSE-L, and BSE agents are essentially preserved during cattle-to-mice transmission (2 mouse brains shown for each agent). B, The Italian (It) and French (Fr) BSE-L isolates have undistinguishable PrP^res profiles that are conserved on second passage. C, Ratio of diglycosylated and monoglycosylated PrP^res species (data plotted as means ± SEM). The BSE-L isolates are represented by triangles from different colors (open, first passage; filled, second passage) and BSE by a black diamond. MM, Molecular markers.