Lyt antigens on the T cells specific for minor histocompatibility antigens: suppression by a Lyt-1+2- regulator.

The T cells involved in the cytotoxic response to minor histocompatibility antigens have been typed for Lyt-1 and Lyt-2 phenotype. BALB/c cytotoxic T cells specific for DBA/2 minor H antigens are H-2-restricted cells of the Lyt-1-2+ phenotype; they are derived for Lyt-1-2+ precursor cells that require collaborative interactions with Lyt-1+2- helper T cells. Suppressor T cells that are generated in vitro and whose function is radioresistant are able to inhibit the cytotoxic response to minor H. Unlike previously described inhibitory cell populations, these inhibitors are Lyt-1+2- cells. The experiments reported here were internally controlled to assess the specificity of the antisera. The results suggest that the cell that inhibits the response to minor H is quite different from the cell that inhibits the response to major H-2 antigens.