Effect of HLA-A, -B functional epitope mismatch on platelet transfusions in patients with hematological diseases

Abstract

Objective To investigate the impact of human leukocyte antigen (HLA) functional epitope mismatch (EM) on the efficacy of platelet transfusion in patients with hematological diseases. Methods HLA genotyping was performed on platelet donors and patients with hematological diseases who applied for platelet serological cross-matching and HLA antigen matching from June 2021 to June 2023 by PCR-SBT method. HLA platelet matching was based on the principle of CREG to select donors for patients. HLA Matchmaker 4.0 software was used to analyze donor-recipient HLA EM information. The expression level and gene distribution of related HLA functional epitope (Eplet) were searched from the international HLA Epitope registry website (www.Epregistry.com.br). Retrospective analysis was conducted on clinical platelet transfusion data to evaluate the impact of HLA EM on platelet transfusion effectiveness. Results Platelet transfusion efficacy showed no correlation with gender and age, but it was associated with platelet matching strategy. When the total number of HLA EMs was less than 20, a lower total number of donor-recipient HLA EMs resulted in higher platelet transfusion efficiency (χ2=19.311, P=0.001) and higher average value of 24 h corrected count increment (CCI)(F=7.737, P<0.001). The total number of donor-recipient HLA EMs had negative correlation with actual 24 h CCI (Rho=-0.322, P<0.001). Further statistical analysis revealed that 17 Eplets were related to the effectiveness of platelet transfusion. The locus distribution of 17 Eplets might be unique to HLA-A (17.6%) or -B (64.7%) or shared between HLA-A and -B (17.6%), and its expression may be high (58.8%) or intermediate (41.2%). Conclusion The total number of donor-recipient HLA EMs is a crucial factor influencing platelet transfusion effectiveness, and several HLA Eplets associated with this effectiveness have been identified.

Keywords

• platelet transfusion refractoriness
• epitope mismatch
• hla
• epitopes