Proliferation of C3H x CBA hybrid lymphocytes in the spleens of irradiated CBA mice: inhibition of this phenomenon by pretreatment of the hosts with C3H x CBA spleen cells.

Lymphocytes from C3H x CBA hybrid mice proliferate intensely in the spleens of irradiated CBA mice. Pretreatment of the CBA hosts with C3H x CBA spleen cells, known to specifically reduce the T-cell reactivity of the hosts against the strongly stimulatory Mls-antigen determined by the C3H-genome, abolished the capacity of the host to promote proliferation of C3H x CBA lymphocytes. In contrast, proliferation of C3H x CBA bone marrow cells, as measured by splenic 59Fe incorporation, was unaffected by such pretreatment. By examining the capacity of spleen cell populations of (C3H x CBA) x CBA back-cross mice to inhibit lymphocyte proliferation, as described above, and to express the C3H-determined Mls-antigen, it was concluded that these two traits are associated.