FIG 5 .

De novo prions cause distinct neuropathology. Brain sections from all mice in each group (n = 5), including terminally sick TgCerPrP mice inoculated with de novo prions (panels A to I), nonclinical WT mice (J to R), and mock-infected WT mice (S to AA), were assessed for vacuolation (column 1; H&E), astrogliosis (column 2; GFAP), and PrP^RES deposition (column 3; PrP^RES) in the cerebellum (A to C, J to L, and S to U), the hippocampus (D to F, M to O, and V to X), and the medulla (G to I, P to R, and Y to AA). TgCerPrP mice exhibited dense punctate PrP^RES plaques in all three areas, whereas PrP^RES staining was absent from WT and control mice. Dense GFAP staining was identified in aged, nonclinical WT mice but was less prominent and more focal in terminal TgCerPrP mice. Vacuolation was observed in WT and TgCerPrP mice but was absent or less intense in the hippocampus. Data from mock-infected WT mice at >300 dpi serve as negative controls. Images shown are representative of all mice in each group. Scale bar, 50 µm.