1,25-DIHYDROXYVITAMIN D-3 REVERSIBLY BLOCKS THE PROGRESSION OF RELAPSING ENCEPHALOMYELITIS, A MODEL OF MULTIPLE-SCLEROSIS

Experimental autoimmune encephalomyelitis (EAE) is an autoimmune disea se believed to be a model for the human disease multiple sclerosis (MS ). Induced by immunizing B10.PL mice with myelin basic protein (MBP), EAE was completely prevented by the administration of 1,25-dihydroxyvi tamin D-3 [1,25-(OH)(2)D-3]. 1,25-(OH)(2)D-3 could also prevent the pr ogression of EAE when administered at the appearance of the first disa bility symptoms. Withdrawal of 1,25-(OH)(2)D-3 resulted in a resumptio n of the progression of EAE. Thus, the block by 1,25-(OH)(2)D-3 is rev ersible. A deficiency of vitamin D resulted in an increased susceptibi lity to EAE. Thus, 1,25-(OH)(2)D-3 or its analogs are potentially impo rtant for treatment of MS.