Elimination of HLA antibodies by platelet adsorption

The presence of HLA antibodies in patient serum or plasma may make antibody identification difficult. These HLA antibodies may mask the presence of clinically significant red blood cell (RBC) alloantibodies. Because platelets strongly express HLA antigens, it is possible to remove HLA antibodies by adsorbing the patient’s serum or plasma using a platelet pool. Large numbers of random platelets are pooled to ensure a wide variety of HLA types are present. Elimination of the reactivity after adsorption suggests the presence of HLA antibodies in the patient’s serum or plasma. The adsorbed patient sample may then be used to evaluate RBC alloantibodies without HLA antibody interference.