Frequency and specificity of alloantibodies to HNA system antigens in donors of blood and blood components

Abstract

Aim. To study the rate of human neutrophil antigens (HNA) alloimmunization in donors of blood and blood components.
 Methods. The study included blood samples of 1,127 donors who donated blood and its components in the Russian Scientific and Research Institute of Hematology and Transfusiology, Saint Petersburg, 635 male and 492 female. 36.18% of female donors were aged between 18 and 30 (n=178) and 63.82% were aged between 30 and 60 (n=314). The medical histories of all donors did not contain the records about the transfusion of blood components. Screening and identification of HNA alloantibodies were performed using the flow cytometric granulocyte immunofluorescence test with monoclonal antibodies CD16-PE, CD45-PC7, CD19-APC, Goat F(ab')2 Anti-Human IgG-FITC and the panel of donor neutrophils with detected HNA genotypes.
 Results. The frequency of HNA alloantibodies in blood donors was 0.35% (n=4). No HNA alloantibodies were found in the male donors. Alloantibodies were detected only in female blood donors aged between 30 and 60. HNA antibody frequency in female donors was 0.81%. It were detected anti-HNA-1a, anti-HNA-3b and anti-HNA-4b antibodies of the IgG immunoglobulin class. In one donor, the specificity of antibodies could not be established. To establish whether detected antibodies in immunized donors were alloantibodies, HNA genotypes were determined.
 Сonclusion. HNA alloantibodies occur with low frequency and are determined in 0.35% of blood donors. Alloantibodies were detected only in female donors and were directed against HNA-1a, HNA-3b and HNA-4b. The frequency of HNA antibodies in female donors was 0.81%. HNA genotyping confirmed that detected antibodies were alloantibodies.