The toxic shock syndrome toxin-1 induces anergy in human T cells in vivo.

TSST-1 is a Staphylococcus aureus-derived superantigen which has been implicated in the pathogenesis of toxic shock syndrome. In mice, superantigen-induced proliferation is followed by deletion or anergy of reactive T cells. So far, superantigen-induced T-cell anergy has not been observed in humans. We therefore examined PBMCs derived from a 15-year-old patient suffering from severe toxic shock syndrome. Markedly elevated levels of circulating TSST-1-reactive T cells were found by cytofluorometric analysis. Upon in vitro restimulation with TSST-1, hyporesponsiveness of TSST-1-responsive V beta 2+ T cells was detected, thus confirming results obtained in the murine system.