title: Promotion of incompatible allograft acceptance in rhesus monkeys given posttransplant antithymocyte globulin and donor bone marrow. I. In vivo parameters and immunohistologic evidence suggesting microchimerism.
abstract: This report extends previous studies demonstrating that prolonged acceptance of incompatible kidney allografts in rhesus monkeys can be achieved by a short recipient rabbit antithymocyte globulin (RATG) treatment course followed by donor bone marrow infusion on day 12 without a requirement for chronic immunosuppression. Serial studies of antilymphocyte cyctotoxic antibody in recipients' sera following RATG injections showed pan-lymphocyte-reactive antibody present until day 10 posttransplant. On days 11 and 12, pan-lymphocyte-reactive antibody was no longer detectable, but cytotoxic antibody specific for mature T cells remained in recipients' sera. These findings might explain the critical time relationship between antithymocyte globulin treatment and donor bone marrow infusion, and further suggest that the tolerance-promoting cell in donor bone marrow is not a mature T cell, but rather a pre-T or a non-T cell. Finally, it was found that this treatment protocol resulted in development of lymphoid nodules in the transplanted kidney that express a CD8-positive, FcIgG-receptor-positive phenotype and appear to be of donor origin. The possibility of a veto cell type of mechanism is discussed as an explanation for the promotion of allograft acceptance in this model.
mesh_terms: D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface / Q000032:analysis; D000961:Antilymphocyte Serum / Q000008:administration & dosage*; D016026:Bone Marrow Transplantation; D006082:Graft Enhancement, Immunologic; D006085:Graft Survival; D007165:Immunosuppression Therapy; D007519:Isoantigens / Q000032:analysis; D007668:Kidney / Q000648:ultrastructure; D016030:Kidney Transplantation; D008253:Macaca mulatta / Q000276:immunology; D008297:Male; D011182:Postoperative Care; D011961:Receptors, Fc / Q000032:analysis; D013601:T-Lymphocytes / Q000276:immunology*; D014184:Transplantation, Homologous
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D000961:Antilymphocyte Serum; D007519:Isoantigens; D011961:Receptors, Fc