EVIDENCE FOR A VIRAL SUPERANTIGEN IN HUMANS

SUPERANTIGENS1-4 bind class II major histocompatibility proteins5,6 and stimulate powerful proliferative responses of T lymphocytes bearing particular V-beta sequences as part of their alpha-beta antigen receptor7. Exogenous bacterial superantigens are responsible for food poisoning and toxic shock syndrome. Murine virus-encoded self-superantigens induce clonal deletion of T lymphocytes. Although superantigen-like properties have been suggested for human immunodeficiency virus-1, no viral superantigen has been identified in humans8. Here we report that the nucleocapsid of the rabies virus is an exogenous superantigen specific for V-beta-8 human T lymphocytes which binds to HLA class II alpha-chains.