Transplantation - the Johannesburg experience. Current status and prospects for specific tolerance

The experience, both clinical and experimental, of the Transplantation Service of the Johannesburg Hospital and Transplantation Research Unit of the University of the Witwatersrand is briefly reviewed. Results of clinical transplantation have not improved in recent years. However, selection of donor-recipient combinations with negative lymphocyte-mediated cytotoxicity and positive B-cell antibody cross-matches predicts success in over 90% of cases. Positive lymphocyte-mediated cytotoxicity cross-matches are associated with a prohibitive rate of graft loss from rejection. The goal of transplantation research is the production of specific immunological tolerance for the graft without the need for using permanent immuno-suppressive drug therapy which is responsible for the major cause of death after transplantation, namely infection. Studies to produce tolerance in the chacma baboon are briefly reviewed. Of all methods of immune modulation studied, none has approached in efficacy and predictability the current work involving total lymphoid irradiation and donor bone marrow infusion. This method holds out great promise for clinical application.