title: Males without apparent alloimmunization could have HLA antibodies that recognize target HLA specificities expressed on cells.
abstract: Human leukocyte antigen (HLA) antibodies, which are involved in the development of transfusion-related side effects such as transfusion-related lung injury, are sometimes found in males without a history of alloimmunization (eg, transplantation and transfusion). Whether HLA antibodies in male donors can interact with their target HLA specificities expressed on cells have not been completely investigated.
  
  
  
  The HLA antibodies detected in 7 male donors were characterized. Flow cytometry and immunocomplex capture fluorescence analysis were performed to evaluate the ability of these antibodies to bind with target HLA specificities expressed on cells. The association of these antibodies with complement was examined using anti-C1q antibody. Sustainability of HLA antibodies over time was compared in 26 male vs 57 female donors.
  
  
  
  The antibodies from all 7 donors recognized intact HLA molecules coated onto microbeads. The antibodies in 2 of 7 donors also recognized their target HLA specificities expressed on cells. Furthermore, the antibodies in one of these 2 donors showed HLA specificities that involved complement binding. Twenty-one of 26 initially positive male donors had turned negative for HLA antibody at least 1 year after their initial positive screening, whereas HLA antibody positivity was maintained for a long time in most female donors.
  
  
  
  Males without apparent alloimmunization could have HLA antibodies that recognize their target HLA specificities on cells and that could potentially modify molecular events in affected cells.
authors.affiliation: Central Blood Institute, Japanese Red Cross Society, Tokyo, Japan.
authors.forename: J
authors.initials: J
authors.lastname: Nakamura
authors.affiliation: Central Blood Institute, Japanese Red Cross Society, Tokyo, Japan.
authors.forename: F
authors.initials: F
authors.lastname: Nakajima
authors.affiliation: Central Blood Institute, Japanese Red Cross Society, Tokyo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kamada
authors.affiliation: Blood Service Headquarters, Japanese Red Cross Society, Tokyo, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tadokoro
authors.affiliation: Central Blood Institute, Japanese Red Cross Society, Tokyo, Japan.
authors.forename: T
authors.identifier: 0000-0003-4559-671X
authors.initials: T
authors.lastname: Nagai
authors.affiliation: Central Blood Institute, Japanese Red Cross Society, Tokyo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Satake
mesh_terms: D000328:Adult; D000918:Antibody Specificity; D000936:Antigen-Antibody Complex / Q000097:blood*; D001782:Blood Donors; D003165:Complement System Proteins / Q000378:metabolism*; D005260:Female; D005434:Flow Cytometry; D006680:HLA Antigens / Q000097:blood*; D006801:Humans; D007518:Isoantibodies / Q000097:blood*; D008297:Male; D011485:Protein Binding; D012737:Sex Factors; D000073617:Transfusion-Related Acute Lung Injury / Q000517:prevention & control
chemical_list: D000936:Antigen-Antibody Complex; D006680:HLA Antigens; D007518:Isoantibodies; D003165:Complement System Proteins
keywords: HLA; HLA antibody; TRALI; blood donors