Molecular mimicry and multiple sclerosis: Degenerate T-Cell recognition and the induction of autoimmunity

Various mechanisms have been proposed for the initiation of autoimmune resp onses by autoreactive T-cell clones. One of these, the molecular mimicry hy pothesis, postulates that myelin-reactive T-cell clones are activated by fo reign antigens. Until recently, sequence homology between self- and foreign antigens was considered necessary for cross-recognition to occur in multip le sclerosis. This article reviews current progress in T-cell receptor immu nology that led to modify this view and proposes a role for degenerate T-ce ll antigen recognition in the induction of autoimmunity.