Renal transplantation between HL-A haploidentical donor-recipient pairs: functional and morphological evaluation.

Fifty-nine recipients received renal allografts from an HL-A haploidentical family member. Immunogenicity of the incompatible haplotype was measured by skin grafts exchanged within each family when possible, and renal allograft recipients were assigned prospectively to two groups depending on the skin graft survival time (Group 2A greater than 15 days; Group 2B less than 15 days). If skin grafts could not be accomplished, the patients were place in an unclassified group, Group 2. Renal function at one and 2 years following engraftment did not differ between the two groups. Mixed lymphocyte stimulation of recipient lymphocytes by mitomycin-treated donor lymphocytes also was comparable in the groups. Histopathological evaluation by light, immunofluorescence, and electron microscopy at least 6 months following allografting did not distinguish between the groups. The only differentiating characteristic was that Group 2A patients did not experience their primary rejection episode until an average of 18 days following transplantation, whereas Groups 2B and unclassified 2 had their initial primary rejection episode at average days 9 and 5, respectively. In our clinical program, matching for HL-A halotypes continues to be the best predictor for long-term renal function in consanguineous renal transplantation.