Bone marrow transplantation in inbred strains of mice. I. The failure of development of normal T cell function following allogeneic transplantation.

Abstract

Lethally irradiated mice reconstituted with allogeneic bone marrow cells usually survive the irradiation damage, but their immune-status is not completely restored. Thus, such mice show depressed humoral antibody responses to thymus dependent antigens, prolonged allogeneic skin graft survival, and their spleen cells display reduced graft-versus-host (GVH) activity when inoculated into newborn F1 hybrid mice. The present study was carried out in order to explore the reason(s) for the depressed immunological activity of allogeneic irradiation chimaeric mice. It was found that these mice had an elevated level of θ positive cells compared to mice transplanted with syngeneic bone marrow cells, but their spleen cells did not show any detectable specific or third-party GVH response. Spleen cells from allogeneic irradiation chimaeras were not able to participate in a collaborative GVH response with lymph node cells either. Possible reasons for the immunological inertness of θ positive cells in allogeneic irradiation chimaeras are discussed.