IDENTIFICATION OF DONOR-DERIVED ANTIGEN-SPECIFIC SUPPRESSOR CELLS IN MURINE BONE MARROW CHIMERAS PREPARED WITH TOTAL-LYMPHOID IRRADIATON

Abstract
The suppressor activity of the spleen cells from bone marrow chimeras prepared with total-lymphoid irradiation was analyzed in vitro. The chimeric spleen cells lacked responsiveness to host-type, but not to 3rd-party, antigens in the mixed-leukocyte reaction (MLR) as judged by (3H)thymidine incorporation and the generation of cytolytic cells. When the donor-type chimeric spleen cells were used as cocultured cells in the MLR, modest nonspecific suppression of (3H) thymidine incorporation and potent antigen-specific suppression of the generation of the cytolytic cells was observed. The donor-type suppressor cells may play an important role in preventing graft-vs.-host disease in vivo.