Risk associations between HLA-DPB1 T-cell epitope matching and outcome of unrelated hematopoietic cell transplantation are independent of HLA-DPA1. Bone marrow transplantation Fleischhauer, K., Fernandez-Viña, M. A., Wang, T., Haagenson, M., Battiwalla, M., Baxter-Lowe, L. A., Ciceri, F., Dehn, J., Gajewski, J., Hale, G. A., Heemskerk, M. B., Marino, S. R., McCarthy, P. L., Miklos, D., Oudshoorn, M., Pollack, M. S., Reddy, V., Senitzer, D., Shaw, B. E., Waller, E. K., Lee, S. J., Spellman, S. R. 2014; 49 (9): 1176-1183

Abstract

HLA-DP antigens are beta-alpha heterodimers encoded by polymorphic HLA-DPB1 and -DPA1 alleles, respectively, in strong linkage disequilibrium (LD) with each other. Non-permissive unrelated donor (UD)-recipient HLA-DPB1 mismatches across three different T-cell epitope (TCE) groups are associated with increased mortality after hematopoietic SCT (HCT), but the role of HLA-DPA1 is unclear. We studied 1281 onco-hematologic patients after 10/10 HLA-matched UD-HCT facilitated by the National Marrow Donor Program. Non-permissive mismatches defined solely by HLA-DPB1 TCE groups were associated with significantly higher risks of TRM compared to permissive mismatches (hazard ratio (HR) 1.30, confidence interval (CI) 1.06-1.53; P=0.009) or allele matches. Moreover, non-permissive HLA-DPB1 TCE group mismatches in the graft versus host (GvH) direction significantly decreased the risk of relapse compared to permissive mismatches (HR 0.55, CI 0.37-0.80; P=0.002) or allele matches. Splitting each group into HLA-DPA1*02:01 positive or negative, in frequent LD with HLA-DPB1 alleles from two of the three TCE groups, or into HLA-DPA1 matched or mismatched, did not significantly alter the observed risk associations. Our findings suggest that the effects of clinically non-permissive HLA-DPB1 TCE group mismatches are independent of HLA-DPA1, and that selection of donors with non-permissive DPB1 TCE mismatches in GvH direction might provide some protection from disease recurrence.

View details for DOI 10.1038/bmt.2014.122

View details for PubMedID 24955785