Indexed on: 21 Jun '17Published on: 21 Jun '17Published in: European Journal of Haematology
HLA-DPB1 matching may impact allogeneic hematopoietic stem cell transplantation (ASCT) outcomes; however, this locus is not in linkage disequilibrium with the remainder of the HLA genes. After classifying HLA-DPB1 mismatches based on T-cell epitope, avoiding non-permissive mismatches may impact survival. We tested this hypothesis at a single academic institution.Retrospective HLA-DPB1 genotyping was performed on 153 adult patients who underwent ASCT and unrelated donors matched for HLA-A, B, C, DRB1 and DQB1 loci (10/10). Using the ImMunoGeneTics/HLA T-cell epitope matching algorithm, mismatch status was classified as permissive or non-permissive.Of 153 donor-recipient pairs, 22 (14.4%) were HLA-DPB1 matches, 64 (42.8%) permissive mismatches, and 67 (43.8%) non-permissive mismatches. DPB1 mismatch increased risk of chronic graft-vs-host disease (cGVHD; RR 2.89 [1.19-9.53],p=0.016) compared with DPB1-matched transplants, but there were no differences in overall mortality, risk of relapse, or acute GVHD (aGVHD). Combining matches and permissive mismatches and comparing to non-permissive mismatches, there was no significant difference in overall survival or relapse; however, patients receiving non-permissive mismatched transplants experienced greater risk of aGVHD overall and severe aGVHD (RR 1.66 [1.13-2.44], p=0.010 and RR 1.97 [1.10-3.59], p=0.024, respectively).In this single center study, HLA-DPB1 matching influenced outcomes of patients undergoing ASCT for hematologic malignancy. This article is protected by copyright. All rights reserved.