Blood Donors Screened for Human Leukocyte Antigen Antibodies

The donor serum samples were initially screened for HLA class I and/or class II antibodies with a panel of fluorescent beads coated with HLA class I and class II antigen preparations using multiplex technology and an enzyme linked immunoassay-based method.

In a study carried out at the University of Texas (Houston, TX, USA), the fluorescent bead test (Luminex; Austin, TX, USA), confirmed that 33 donors were positive for HLA class I and/or II antibodies. The agreement rates between the methods for HLA class I and II antibodies were 21% (7/33) and 6% (2/33), respectively. The DonorScreen ELISA-based method, (GTI; Waukesha, WI, USA), was significantly more specific for HLA class I antibodies than for HLA class II antibodies. A false-positive result was reported for the HLA class I antibody in 2/33 (6%) of the donors and for the HLA class II antibody in 19/33 (58%) of the donors using the DonorScreen method.

A retrospective review of recipients of packed red blood cells (RBCs) and platelets processed from these 33 HLA-immunized male donors were conducted to identify transfusion-related acute lung injury (TRALI) and cognate antigens. HLA antibodies in the male donors corresponding to cognate antigens were found in two recipients of packed RBCs and in three recipients of platelets. Of eight donors positive for HLA antibodies, five did not have a history of blood transfusion.

Transfusion of virtually all blood products is implicated as a cause of TRALI, which can occurs within six hours of receipt of the product. In addition to infusion of packed RBCs, platelets, and fresh frozen plasma, transfusion of allogeneic stem cells and intravenous administration of immunoglobulin, and granulocytes have been implicated as causes of TRALI. The authors concluded that the ELISA method was too sensitive and had a high false-positive rate for the detection of HLA class II antibodies, and therefore excluding possible donors. The study was published in January 2011 in the American Journal of Clinical Pathology.

Related Links:
University of Texas
Luminex
GTI