FcγRs in Health and Disease

Genetic defects affecting the humoral immune response and especially the production of antibodies of the immunoglobulin G (IgG) isotype result in a heightened susceptibility to infections. Studies over the last years have demonstrated the crucial role of Fc-receptors for IgG (Fc gamma Rs) widely expressed on innate immune effector cells in mediating the protective function of lgG. During the last years, additional ligands interacting with Fc gamma Rs as well as additional receptors binding to IgG glycosylation variants have been identified. In this review, we discuss how the interaction of these different ligands with classical and novel Fc gamma-receptors influences the immune response and which strategies microorganisms have developed to prevent them.