Two sequence dimorphisms of DPB1 define the immunodominant serologic epitopes of HLA-DP

Donor-specific anti-HLA Abs and graft failure in matched unrelated donor hematopoietic stem cell transplantation

“…26 In the 5 transplantations in which there was donor engraftment, 2 patients presented with nonpermissive TCE mismatches (DPB1*1001 and DPB1*1401), whereas in the 3 patients without engraftment, 2 presented with nonpermissive TCE mismatches (DPB1*0301 in both of them). The analysis of the TCE mismatches and the anti-DP serologic epitopes defined by our group 27 in previous studies, and additional possible epitopes listed in Table 2, did not identify any specific epitope present in the nonengraftment group that was absent in the group of transplantations with engraftment. Similarly, neither the nature of the crossreactivity nor the ranges of MFIs identified distinctive characteristics between the patients with and without engraftment.…”

A combined DPA1∼DPB1 amino acid epitope is the primary unit of selection on the HLA-DP heterodimer

“…Cano and Fernandez-Vina (2009) described two sets dimorphic amino acid epitopes at positions 56 and 85–87 that together accounted for the majority of DP serological reactivity observed in a sample of solid organ transplant patients. The first sequence dimorphism is found at DPB1 amino acid position 56, with either Ala (A) or Glu (E) at this site.…”

Acute Humoral Rejection in a Zero Mismatch Deceased Donor Renal Transplant Due to an Antibody to an HLA-DP α

“…In addition, antibodies to DPB1 have also been implicated in chronic humoral rejection in retransplants and have been found to share epitope with other HLA molecules (10). Further epitope classification of DPB1 has been pursued, which has helped in the identification of antibodies directed against them (11). It is known that failed renal allografts can elicit an antibody response to DP ␣ (12).…”