Severity of Transfusion-Related Acute Lung Injury in mice expressing human FcgRIIA is determined by platelet-released serotonin

Objective Transfusion-related acute lung injury (TRALI) remains a major cause of transfusion-related fatalities. TRALI can occur after transfusion of blood products containing allogeneic antibodies targeting cells of the recipient. The involvement of the human Fcg receptors in this type of TRALI has been poorly assessed. FcgRIIA/CD32A is an activating low affinity receptor for immunoglobulin G (IgG) expressed on human platelets and immune cells, whereas no corresponding ortholog is present in mice. Therefore, since the current murine models incompletely recapitulate the human immunology, our understanding of the pathogenesis of antibody-mediated TRALI is partial. Our study aimed at evaluating the contribution of FcgRIIA/CD32A in a model of antibody-mediated TRALI in transgenic mice expressing this human receptor.