The effect of blood transfusion and immunosuppression on organ graft survival : a study in dogs and rats

Since the first preliminary report by Opelz et al. (1973a) on the beneficial effect of blood transfusions, it has gradually become evident that blood transfusions do have such an effect on renal allograft survival. Nevertheless, some physicians are still reluctant to adopt a deliberate blood transfusion regimen for fear of sensitization. The development of cytotoxic antibodies may delay transplantation for an indefinite time for some patients. This possible danger of sensitization initially gave rise to the policy of avoiding blood transfusions in kidney transplant recipients and it took many years of study, experimentation and discussion before the present situation of general acceptance was established. With respect to the clinical application of a deliberate blood transfusion policy, several questions remain to be answered regarding the optimal number and the timing of transfusions, the antigenic composition of the transfusate and the influence of immunosuppressive therapy on the expression of the blood transfusion effect. The effect of blood transfusions on kidney graft survival has only been studied in recipients treated with azathioprine and prednisolone for postoperative immunosuppression. It still has to be investigated if a beneficial effect of pretransplant transfusions would be demonstrable without conventional immunosuppression or in combination with postoperative administration of the novel immunosuppressant cyclosporin A. Cyclosporin A was recently discovered in the Sandoz Laboratories during a screening program for antimycotics; its powerful immunosuppressive properties were described by Borel et al. (1976). It has been tested in a variety of experimental animal transplantation models. Preliminary data are available on its clinical effectiveness and side effects. Some of these side effects are serious and it is still too early to be sufficiently informed about the long-term effects of the drug. Further questions awaiting evaluation pertain to the optimal dose of the drug, its potency to prevent rejection in sensitized recipients, the possible interference with other modes of treatment, and the possibilities of conversion to other immunosuppressants. It was the objective of the present studies to elucidate the items mentioned above.