Improved renal allograft survival using the mixed lymphocyte culture for selection of nonidentical living related donors.
Our results concur with earlier published work, by other groups, showing that LRD-recipient pairs with low MLC stimulation usually have better and more prolonged graft success than do those with higher stimulation. Specific HL-A compatibilities or incompatibilities did not seem to affect these results, nor did the presence of an increased number of common loci, short of increasing the apparent chromosome compatibility. The presence of pre-transplant cytotoxic antibodies, in patients with a high MI, however, may unfavorably affect the LRD transplant. The overall results of our LRD transplant experience is shown in Figure 1, and superimposed upon Figure 2, is the current extrapolation of data showing MLC stimulation and haplotype success. Thus, it appears that graft survival may be improved and more closely approach the levels seen in a full-house, diplotype match, by using the MLC results in considering patients for transplantation. Not all patients with a high MLC, however, (see table) reject their grafts and it is impossible to predict pre-transplant who will develop specific allograft enhancement. Before the MI becomes a specific criteria for transplant selection, additional studies of patient stimulation in MLC should be done. Suppression of stimulation by donor cells in autologous serum, as compared to the response to unrelated controls, might provide pre-transplant clues to the presence of enhancing factors. Such studies could provide an index that would be more meaningful than the MI in AB sera alone. Since overall results from both our series and from the Transplant Registry continue to indicate better long term graft survival for LRD than for cadaver transplants, and since the evidence suggests that a successful transplant offers a patient a better quality of life, as well as decreased morbidity and mortality compared to concomitant time spent on hemodialysis, continued LRD transplants with high MI is warranted in some circumstances with the patient's understanding of the overall outcome and backgrouns. Until in vitro tests can be more predictive of individual rather than statistical graft success, the patient with an LRD and a high MI should be given a complete explanation of the probabilities for success or failure, and he and the donor allowed to make an informed decision. The following are guidelines that we proposed for the selection of LRD transplants: 1. Availability and willingness. 2. Medical and psycho-social clearance. 3. ABO compatibility. 4. Negative direct crossmatch. 5. HL-A diplotype or haplotype. 6. MI less than 10 if possible, with or without HL-A antibodies. 7. MI greater than 10 with no HL-A antibodies, if possible. 8. MI greater than 10, with HL-A antibodies, if both donor and recipient clearly understand the enhanced chance for failure.