Cytotoxic T cells recognize male antigen and H-2 as distinct entities.

XX cells from XX/XY hemopoietic chimeras do not express male determinants in a way to render them either stimulators or targets for male-specific cytotoxic lymphocytes. XX- but not XY-responder T cells from chimeras can be activated to lyse allogeneic male target cells; T cells from normal XX mice depleted of alloreactive T cells, however, cannot be sensitized to lyse allogeneic XY targets. The results imply that T cells recognize the Y-antigen and H-2 as distinct entities, and that in chimeras, they acquire the potential to react against allogeneic XY cells.