In conclusion, our study suggests that suppression of pro-inflammatory iNOS+ macrophages and ratio of iNOSe versus Ym-1+ macrophages/microglia, C3 deposition, and development of reactive C3+ astrocytes in the CNS by DMF treatment could contribute to the reduction in demyelination and axonal loss in MS. Here, NOS2 is linked to myeloid sarcoma.