The prevalence of leucocyte alloantibodies in blood donors from South China

SUMMARY Background Several studies had demonstrated that leucocyte antibodies including anti-human leucocyte antigen (anti-HLA) antibodies (class I and class II) and anti-human neutrophil antigen (anti-HNA) antibodies (HNA-1, -2 and -3) present in the blood products are responsible for transfusion-related acute lung injury (TRALI). Therefore, selection of blood products exclusive of anti-HLA and anti-HNA antibodies may lower the risk of TRALI reaction. However, the prevalence of leucocyte antibodies among blood donors in China is currently not known. Study design and methods Blood samples were collected from 454 male and 560 female donors (143 nulliparous and 417 multiparous female). HLA class I and II antibodies were analyzed by bead assays. Anti-HNA-1 and -2 antibodies were screened by the LABScreen assay (One Lambda Inc.), and HNA-3 were detected by antigen capture assay, and confirmed by the granulocyte agglutination test (GAT). Results Screening of the total cohort showed higher prevalence of HLA antibodies in female compared with male donors (19·64 vs 4·63%). We found antibodies against HLA class I (13·21%) and HLA class II (11·43%) in 560 female donors. The most frequent antibodies against HLA class I and II in parous females (n = 69) reacted with were A*11 (28·81%), B*07 (42·37%), Cw*07 (20·34%) and DRB1*04 (40·43%) molecules. Among 778 donors (randomly selected from 1014 donors), we found three donors with neutrophil reactive antibodies, two against HNA-2 and one without known specificity. Anti-HNA-3 antibodies were not found so far. Conclusion In this study, we found alloimmunization against HLA class I, II and HNA in 4·63, 24·70 and 0·39%, respectively, in our female blood donors, indicating that the use of plasma containing blood products from parous female blood donors without HLA antibodies pre-testing may increase the risk of TRALI reaction. Although immunization against HNA seems to be a rare event in China, further observation is necessary to decide the necessity of HNA antibodies screening in our blood donors.