To induce tolerance in patients receiving allografts has been a goal of transplantation research in the past 50 years. However, with increasing experience of patient management and new drug regimens, it is difficult to imagine that a protocol to produce tolerance between any possible donor and recipient would be feasible in the foreseeable future. We already have full tolerance whenever there is a successful bone marrow transplant, traditionally the whole immune system is destroyed by irradiation and/or drugs and replaced with the donor's marrow. Success usually requires close matching of HLA antigens between donor and recipient and usually in fact the use of bone marrow from an HLA identical sibling.

Keywords: organ