Histopathology of the rats receiving transplants fromFigure 3A and repeated experiment. (A-H) Characteristics of MOG-induced EAE in a DA rat not undergoing BM transplantation. Large, confluent areas of demyelination and macrophage infiltration in the dorsal funiculus of a representative untreated DA rat. Macrophages containing LFB-positive myelin degradation products indicative of ongoing demyelination are shown in the inset (A; LFB-periodic acid-Schiff [PAS] staining). Infiltration by foamy macrophages/activated microglia cells shown by immunohistochemistry for ED1 (B; brown reaction product). Dense deposits of immunoglobulin (C) and C9 (D) in the lesions (plaque edge indicated by arrows). CD3⁺ T cells scattered in the lesional area (E). APP-positive axonal profiles indicative of acute axonal damage (F; plaque edge indicated by arrows). Acutely damaged axons indicated by arrows (G [enlarged from panel F]; brown reaction product). Reduction in axonal density as demonstrated by Bielschowsky silver impregnation; plaque edge indicated by arrows (H). (I-N) DA rat immunized with MOG and receiving DA BM transplants. No evidence for demyelination (I), macrophage infiltration (ED1) (J), immunoglobulin (K) and C9 deposition (L), acute axonal damage (APP) (M), or axonal loss (N) in a representative immunized and treated DA rat. A,B,I-N: bar, 100 μm; C,D,F,H: bar, 50 μm; E,G: bar, 20 μm. Light microscopic images were taken using a Color View digital camera (Soft Imaging System, Muenster, Germany) mounted on an Olympus BX51 microscope (Olympus, Tokyo, Japan). Panels A, B, and I-N were taken at a magnification of 100 × (10 ×/0.3 NA objective); C, D, F, H, at 200 × (20 ×/0.5 NA objective); and E, G, and inset of A, at 400 × (40 ×/0.75 NA objective). Images were imported using Analysis software (Soft Imaging System), and Adobe Photoshop CS 8.0.1 (Adobe Systems, San Jose, CA) was used to create the color plate.