Not every superantigen induces tolerance in vivo.

We have distinguished TSST-1 from SEA and SEB with respect to its in vivo effect on T cells, that is, SEA and SEB induce tolerance in treated mice whereas injection of TSST-1 does not result in tolerance. Therefore, previous observations which relate superantigens to the suppression of reactive V beta TCR T cells seem difficult to generalize to all bacterial superantigens. Since the effects of superantigens are beginning to be exploited for immunotherapy, the differences between TSST-1 and SEB in terms of induction of tolerance suggest that all superantigens may not generally be useful in this respect. Each superantigen obviously should be studied in vivo in respect to T cell tolerance induction.