Antigen-induced apoptosis in developing T cells: a mechanism for negative selection of the T cell receptor repertoire.

Herein we have investigated the ability of antigen to induce thymocyte death by apoptosis on the basis that this may be the mechanism for the deletion of autoreactive cells during T cell development. We show that the ability of the bacterial "superantigen" staphylococcal enterotoxin B to cause specific depletion of V beta 8+ cells when added to thymus organ cultures is accompanied by DNA degradation into oligonucleosomal fragments, indicating that depletion involves apoptosis. Our results provide the first direct evidence that antigen-induced apoptosis can be triggered in developing T cells.