Effect of HLA-DR mismatch on lung transplant outcome

Human leukocyte antigen (HLA) matching clearly plays an important role in outcome for kidney and heart transplantation, but the role of HLA-DR matching has not been definitively demonstrated for lung transplantation. We performed a retrospective analysis of a combined cohort of 242 lung transplant recipients transplanted at UW (N5117) and UG (N5125) who survived 1 or more months post-transplant. Significantly poorer outcome, defined as the development of bronchiolitis obliterans syndrome (BOS) or graft loss, was observed for HLA-DRmismatched recipients. The combined, center-stratified outcome data revealed a significant difference (p50.0005) in outcome for recipients with 2 HLA-DR (N5118) mismatches vs. 0 or 1(N5119). Outcome was best for those with no mismatches (N520), intermediate for those with 1 mismatch (N599), and worst for those with 2 mismatches (N5118). In contrast, the center-stratified statistical analysis of mismatching of class I (HLA-A or HLA-B) antigens demonstrated no significant effect on outcome. Our data suggest that HLA-DR matching has an important survival effect on outcome in lung transplantation, but we failed to demonstrate any effect of HLA-A or HLA-B matching.