(A) Bielschowsky’s silver impregnation for axons showed a reduction of axonal density in the white matter of the spinal cord (arrows) of a vehicle-treated mouse as compared with ABS-75–treated animal. The axonal pathology analysis was performed after disease progression at the end of the disease course. Original magnification, ×50 (top panels); ×100 (bottom panels). Quantification of stained spinal cord sections by image analysis (ImageJ; NIH) confirmed a reduction in axonal loss when comparing ABS-75– and vehicle-treated animals. P < 0.02; Student’s t test, mean ± SD. (B) Luxol fast blue staining showed a reduction in the myelin content in the white matter of the spinal cord (arrows) of vehicle-treated mice as compared with ABS-75–treated animals. Original magnification, ×50 (top panels); ×100 (bottom panels). Quantification of stained spinal cord sections showed a reduction in demyelination when comparing ABS-75– and vehicle-treated animals. P < 0.01. Student’s t test, mean ± SD. (C) Neurofilament H staining, which identifies smaller nerve fibers (depicted in red; white arrows) shows reduction in nerve fiber density (percentage of the area within the ventral column of the white matter stained for neurofilament H) in controls (3.96% ± 1.43%) versus ABS-75 (16.13% ± 5.13%). P < 0.01; Student’s t test, mean ± SD. Nuclei of infiltrating cells stained blue (yellow arrows), and GFAP stained green. Original magnification, ×400. (D) Bielschowsky’s silver impregnation for axons showed no significant reduction of axonal density in the white matter of the spinal cord of SJL mice at the end of the disease course as compared with naive animals. Original magnification, ×100.