Histological lesions in H&E stained sections of brain and spinal cord were detected only in Gnptab^−/− mice.

(A) Swollen dystrophic axons/neurites in piriform cortex of 12-month-old Gnptab^−/− mice, but absent in WT controls (B). (C) Axonal spheroids were present in the afferent nerves (thick arrow) and dystrophic neurites (thin arrows) were concentrated in the superficial laminae of the dorsal horn grey matter of the spinal cord of Gnptab^−/− mice, but were entirely absent in the spinal cords of WT controls (D). (E) Cerebellum of 10/12-month-old Gnptab^−/− mice with Purkinje cell loss (arrow) not seen in the Purkinje cell layer (arrow) in WT controls (F). (G) Staining for GFAP in cerebellum of 6-month old Gnptab^−/− mice showing bilaterally symmetrical parasagittal bands (arrows) of activated Bergmann glial cells that coincided precisely with zones of Purkinje cell loss. (H) Negative GFAP staining of Bergmann's glia was evident in WT mice. (Figures A-F 40X, Bar  =  100 mm; Figures G and H; 4X, Bar  =  1 mm)