Prevention and reversal of superantigen‐induced anergy by contact allergen exposure

Abstract The superantigen Staphylococcal enterotoxin B (SEB) and the contact allergen 2,4‐dinitrofluorbenzene (DNFB) both react with Vβ8+ T‐cells delivering distinct signals. Pre‐treatment with DNFB painted onto the same skin site where SEB was to be injected, prevented the induction of anergy in Vβ8+ T‐cells that was otherwise induced after SEB had been injected intradermally over a period of 2 weeks. Application of the irritant sodium dodecyl sulfate (SDS) instead of DNFB did not exert this effect. Application of DNFB at a site distant from the site where SEB was injected resulted in a much weaker inhibitory influence on the induction of anergy by SEB. Established anergy of Vβ8+ T‐cells (proliferative non‐responsiveness to SEB in vitro that could be overcome by addition of exogenous interleukin 2 (IL‐2)) could be largely reversed by repeated cutaneous exposure to DNFB painted to the site where SEB had been injected before. The moderate decrease of Vβ8 + T‐cells normally induced by SEB‐treatment was also partially prevented by DNFB pre‐treatment. The data indicate the importance of the sequence of signals delivered to T cells and the plasticity of the responsiveness of this cell type.