First challenge of C57BL/6 mice with monkey C- and L-BSE prions.

(A) Western blot analysis of PrPSc in the brain, spleen, and distal region of the ileum of representative mice. Ctrl (control inoculum); brain homogenates of a healthy monkey. dpi; days post-inoculation. Mr; relative molecular mass. PrPSc was detected using the antibodies 44B1 or SAF-84, and VeriBlot anti-mouse IgG. (B) Western blot analysis of levels of GFAP and HSP25 in the brains of mice. GAPDH and neuronal class III β-tubulin (tubulin) were used as loading controls. (C) Posterior footprints of representative mice subjected to first challenge with monkey C- and L-BSE prions, and a mouse injected with control inoculum (Ctrl as in (A)). The posterior limbs were dipped in India ink, and mice were allowed to walk on sheets of paper.