THE SMALL HEAT-SHOCK PROTEIN ALPHA-B-CRYSTALLIN AS CANDIDATE AUTOANTIGEN IN MULTIPLE-SCLEROSIS

THE identification of key antigens in human autoimmune diseases is a c rucial step towards the development of specific intervention. The auto antigen(s) relevant to multiple sclerosis (MS) probably reside in myel in of the central nervous system, the target of the disease(1). Here w e examine proliferative responses of human peripheral blood T cells to the complete collection of myelin proteins fractionated by reversed-p hase high-performance liquid chromatography. Myelin isolated from MS-a ffected brain contained a single protein fraction to which T cells fro m MS patients and from healthy controls showed dominant responses. Thi s highly immunogenic protein was identified as alpha B-crystallin, a s mall heat-shock protein. Immunohistochemical examination of MS lesions revealed the presence of oligodendrocytes and astrocytes with raised alpha B- crystallin expression, which were not found in unaffected mye lin. Our findings indicate that alpha B-crystallin serves as immunodom inant myelin antigen to human T cells when expressed at the elevated l evels found in active MS lesions.