BMT leads to a reduction in infiltrates, demyelination, and axonal damage in the CNS. Representative spinal cord sections from untreated EAE mice, mice undergoing BMT, or mice undergoing BMT in combination with castration 12 days after EAE induction. Sections stained with (A) hematoxylin and eosin for infiltration, (B) Luxol fast blue for demyelination, and (C) Bielschowsky silver impregnation for axonal damage illustrating that EAE mice treated with either BMT only or BMT in combination with castration had little or no inflammatory infiltrates, demyelination, and axonal damage compared with untreated EAE mice. (D) Flow cytometric analysis of infiltrating lymphocytic population as described by CD45⁺CD4⁺CD11b⁻ surface marker staining. Whereas proportions of infiltrating lymphocytes did not alter, their number significantly decreased in Cx/BMT mice. (E) Microglia cell analysis by flow cytometric analysis, as determined by CD45^lo CD11b⁺ cell surface staining, demonstrated a significant reduction in the number of activated microglia cells in Cx/BMT-treated mice than the BMT-only mice, however proportions remain unchanged. (F) Macrophage and granulocyte populations in the CNS as examined by flow cytometric analysis of the CD45^hiCD11b⁺ population. Graphed results indicate that there was no significant alteration between treatment groups in proportion and cellularity. Results are expressed as mean plus or minus SEM from 2 or more independent experiments. *P < .05 versus BMT only. Original magnification ×60.