Objective  To systematically evaluate the effect of HLA-DPB1 mismatch on the clinical outcomes of unrelated donor hematopoietic stem cell transplantation.

  Methods  Relevant studies analyzing the effect of HLA-DPB1 mismatch upon the clinical outcomes of unrelated donor hematopoietic stem cell transplantation published from January 1995 to December 2016 were retrieved from the PubMed, Embase, Center of International Bone Marrow Transplant Registration, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Chinese BioMedical Literature Database and China National Knowledge Infrastructure database. The survival rate, the incidence of implantation failure, graft-versus-host disease (GVHD), recurrence rate, transplantation-related mortality rate and other adverse events were analyzed by Review Manager 5.3 software. Funnel plot was utilized to assess the publication bias.

  Results  A total of 19 literatures consisting of 26 634 patients were retrieved. Meta-analysis demonstrated that compared with the recipients in the HLA-DPB1 match group, those in the HLA-DPB1 mismatch group had lower disease-free survival rate and overall survival rate in non-T cell-depleted transplantation. In the HLA-DPB1 mismatch group, the incidence of severe GVHD and transplantation-related mortality(TRM) rate were higher. And the TRM rate of two loci mismatch was more evident than that of one locus mismatch.

  Conclusions  HLA-DPB1 locus exerts significant effect on the survival rate and incidence of adverse events after unrelated donor hematopoietic stem cell transplantation. The status of HLA-DPB1 match should be considered when selecting the unrelated donors.