[Analysis of the distribution frequencies of HLA-A and HLA-B alleles in patients with immune-mediated Platelet transfusion refractoriness].

Abstract

Objective: To analyze the distribution frequency and characteristics of HLA-A and HLA-B loci in patients with immune-mediated Platelet transfusion refractoriness (iPTR) in order to provide data support for investigating HLA gene matching strategies for platelet transfusion and improving transfusion efficacy.

Methods: A total of 532 iPTR patients who applied for gene matched platelet at the Blood Center of Zhejiang Province between January 2020 and June 2024 were selected as the study subjects. Genomic DNA was extracted from peripheral blood samples from the patients, and the HLA-A and HLA-B loci were detected simultaneously using a PCR-sequence specific oligonucleotide probe method (PCR-SSO) and PCR-sequence based typing (PCR-SBT). Statistical methods were used to analyze the distributions of HLA-A and HLA-B antigens and genotypes on the platelet surface of the patients. An analysis of the differences was conducted to compare the results with the Common and Well-Documented (CWD) allele in the Chinese population from the China Marrow Donor Program (CMDP) database. This study was approved by the Medical Ethics Committee of the Blood Center of Zhejiang Province (Ethics No.: Provincial Blood Center Ethics Review 2023Yan No.004).

Results: Among the 532 iPTR patients, 19 HLA-A antigens (including 32 HLA-A alleles) and 37 HLA-B antigens (including 64 HLA-B alleles) were detected. The antigens with the highest frequencies were A2, A11, A24, and B46, B60, B58, with the combined distribution frequency of the top three antigens reaching 71.43% and 36.94%, respectively. The most prevalent alleles of the HLA-A and HLA-B loci were A*11:01, A*24:02, A*02:07 and B*46:01, B*40:01, B*58:01. The frequencies of common alleles A*01:01, A*02:07, A*11:02, A*30:01 and B*13:02, B*27:04, B*40:01, B*44:03, B*46:01 showed significant differences (P < 0.05) compared to the normal population in the CWD table (version 2.4) of CMDP.

Conclusion: The HLA-A and HLA-B genes of the iPTR patients showed great divergence, and the distribution frequencies of certain alleles have differed significantly from those of the normal population. This study has provided genetic data for exploring the molecular mechanism underlying iPTR, which is of significant clinical importance for searching HLA gene matched donors.