Prevalence of granulocyte antibodies in never allo-exposed female and male donors.

BACKGROUND: Foetal/neonatal allo-immune neutropenia (FNAIN) is a serious condition usually resulting from immunisation of the mother to paternally inherited neutrophil antigens of the foetus. Understanding the biology of female immunisation against neutrophils could help predict or prevent FNAIN.

OBJECTIVES: To quantify differences in the prevalence of specific and pan-reactive granulocyte antibodies, between allo-exposed and never allo-exposed male and female blood donors.

METHODS/MATERIALS: We previously reported the prevalence of granulocyte antibodies in healthy male and female blood donors. Here, we compare specific vs. pan-reactive antibodies.

RESULTS: The prevalence of specific granulocyte antibodies was similar in male [1.0%; 95% confidence interval (CI): 0.70-1.4] and female nulliparous blood donors (0.87%; CI: 0.029-1.7) and doubled after pregnancies (1.8%; CI: 0.52-3.0). In contrast, pan-reactive antibodies were almost three times less common in male (0.81%; CI: 0.50-1.1) compared to female nulliparous blood donors (2.3%; CI: 0.91-3.8) and were half as high after pregnancies (1.1%; CI: 0.58-1.7).

CONCLUSION: We found unexpected differences between male and female blood donors. Determining the clinical relevance of the pan-reactive antibodies requires further research, but none of the tested blood donors experienced any symptoms of neutropenia.