We have discovered that LRG-47 (also called p47 GTPase), plays a central role in the pathogenesis of multiple sclerosis, and that inhibition of LRG-47 activity by anti-LRG-47 antibodies or of LRG-47 expression by siRNA dramatically reduce the pathology and symptoms of multiple sclerosis. Certain embodiments of the invention are directed to the therapeutic use of anti-LRG-47 antibodies (mouse or rabbit or other antibodies that are humanized or human antibodies to LRG-47, preferably antibodies made against human LRG-47) or siRNA or antisense nucleotides that specifically hybridize with the gene or mRNA or cDNA encoding human LRG-47 to treat or prevent multiple sclerosis and other autoimmune diseases that are T-cell-mediated. Other embodiments are directed to methods for the diagnosis of multiple sclerosis or to determining the aggressiveness of multiple sclerosis by determining the amount of human LRG-47 or LRG-47 mRNA in a biological sample from the patient.
