title: Platelet transfusions can induce transplantation tolerance.
abstract: Recently we have shown that the induction of antibodies against the H-2 antigens after multiple platelet transfusions is due to leukocyte contamination of the platelet suspensions. Pure platelets are not able to induce a primary antibody response. The present study shows that the platelets, however, can be recognized by the immune system but they induce a suppression of the response. Mice pretreated with donor platelets will not give a primary antibody response upon a subsequent injection of donor leukocytes and the survival of donor skin grafts will be prolonged. Similar results were obtained by pretreatment of the responder mice with heat-treated donor leukocytes. Furthermore, repeated injections of heat-treated leukocytes of the recipient strain to the donor before bone marrow grafting, will delay graft-versus-host mortality. These data show that cells which have only class I antigens on their surface and no activating class II antigens, induce a suppression of the response against class I antigens.
mesh_terms: D000818:Animals; D000917:Antibody Formation; D001803:Blood Transfusion; D016026:Bone Marrow Transplantation; D006085:Graft Survival; D006358:Hot Temperature; D007108:Immune Tolerance; D007962:Leukocytes / Q000276:immunology; D051379:Mice; D008815:Mice, Inbred Strains; D017713:Platelet Transfusion; D014181:Transplantation Immunology