Both permissive and nonpermissive HLA-DPB1 mismatches can induce polyclonal HLA-DPB1 specific immune responses in vivo and in vitro

Clinical studies have indicated that human leukocyte antigen (HLA)-DPB1 functions as a classical transplantation antigen in allogeneic stem cell transplantation (SCT). Mismatching for HLA-DPB1 was associated with an increased risk of graft-versus-host disease (GVHD) but also a decreased risk of disease relapse. 1,2 However, some studies showed that specific HLA-DPB1 mis-matches were associated with poor clinical outcome. It was suggested that this unfavorable effect was caused by differences in immunogenicity between HLA-DPB1 alleles. An algorithm defining permissive and nonpermissive HLA-DPB1 mismatches was developed based on cross-reactive T-cell reactivity patterns. It was suggested that permissive mismatches would not result in T-cell Table 1. Comparison of demographic, clinical, and laboratory characteristics between ISM subgroups Characteristic No. (%) of patients Median (range) ISM-other, no. (%) BMM, no. (%) SSM, no. (%) P Total no. of ISM 159 -101 (63) 36 (23) 22 (14) Demographic characteristics Male 69 (43) -39 (39) 21 (58) 9 (69) NS Age, y -49 (19-84) 48 (21-84) 45 (19-77) 64 (38-78) .