Human neutrophil antigens (HNA) are involved in the pathogenesis of a variety of clinical conditions, such as neonatal immune neutropenia (NIN), refractoriness to granulocyte transfusions, alloimune neutropenia after bone marrow transplantation, febrile transfusion reactions, and transfusion-related acute lung injury (TRALI). The accurate detection of granulocyte antibodies is essential for the diagnosis and prevention of the clinical conditions in which these antibodies are involved, especially TRALI. The international granulocyte immunology workshop recommends the use of granulocyte agglutination test (GAT) and granulocyte immunofluorescence test (GIFT) for the screening of granulocyte antibody, and the use of monoclonal antibody-specific immobilization of granulocyte antigen (MAIGA) assay for the determination of the antibody specificity. Presently, however, no single technique available is enough to detect all clinically relevant granulocyte antibodies. Here, we describe the advantages and disadvantages of the mixed-passive hemagglutination (MPHA) assay in the general context of granulocyte serology.