IMMUNOLOGICAL-TOLERANCE TO RENAL-ALLOGRAFTS AFTER BONE-MARROW TRANSPLANTS FROM THE SAME DONORS

A severe potential complication of clinical bone marrow transplantation is the eventual development of end-stage renal failure, probably as a direct consequence of chemotherapy and radiation, by as many as half of the long-term survivors. There have been no clinical descriptions of the use of renal allografts in recipients of successful bone marrow grafts who went on to develop subsequent kidney failure. This report describes two patients receiving bone marrow transplants from HLA-identical siblings who, 3 and 6 years later, accepted kidneys from the same donors. Although we did not use any immunosuppressive therapy, we did not observe any rejection episodes, and both renal allografts continue to function normally more than 1 and 2 years later. One of the patients developed a transient episode of mild graft-versus-host-disease. These are the first reported cases of specific acquired immunologic tolerance to vascularized whole-organ allografts in humans.