Fig. 1

Discriminatory Western immunoblot of brain samples from cattle inoculated with the pre-1975 and post-1990 scrapie brain pools. Lanes 1–9 cattle inoculated intracerebrally with the pre-1975 scrapie pool: P75-1, P75-2, P75-3, P75-4, P75-5, P75-6, P75-7, P75-8 and P-75-9. Lanes 10–16 cattle inoculated intracerebrally with the post-1990 scrapie pool: P90-2, P90-3, P90-1, P90-4, P90-5, P90-6 and P90-7. Lanes L, H, C, O controls: L-type BSE, H-type BSE, classical BSE, ovine scrapie. Lanes M molecular mass marker. Animal P90-4, sample lane 13, was an outlier with a lower molecular mass of the unglycosylated band with mAbs Sha31 and SAF84 compared to the other samples previously tested with mAb 6H4. The sample of the other outlier P90-5 (determined previously by testing caudal medulla), sample lane 14, consisted here of rostral medulla and gave a molecular profile similar to the others of the group as observed in the original blot when both brain samples were tested [2]. The lane numbers of those cattle that provided the inocula for bank voles and mice are underlined.