Superantigens in autoimmune disease.

The recent identification of superantigens (of retroviral origin in mice and bacterial origin in humans) has given rise to several hypotheses linking superantigens to autoimmune responses. The most compelling argument in support of such a link is restricted V beta gene usage by lymphocytes in rheumatoid joint fluid and Sjögren's syndrome salivary tissue. However, a substantial body of evidence from mouse models militates against a link between the presence of self-superantigen-reactive T-cells and the development of autoimmune disease. Nevertheless, superantigens are powerful instruments for investigating tolerance.