Humoral autoimmunity as a mediator of CNS repair

Autoimmune responses directed against the central nervous system (CNS) have generally been considered pathogenic in nature. Although there are several well understood conditions in which this is the case, there is also a grow ing body of experimental evidence to show that both the cellular and humora l immune responses can promote tissue repair following CNS injury and disea se. Our laboratory has used a mouse model of chronic demyelinating disease to characterize a class of polyreactive IgM autoantibodies that react with oligodendrocyte surface antigens and promote myelin repair. By screening a large number of human monoclonal antibodies, we have found that IgM antibod ies that react with CNS tissue are relatively common. Autoreactive IgM anti bodies might constitute an endogenous system for tissue repair, and therefo re these antibodies could be of value as therapeutic reagents.