Low affinity immunoglobulin gamma Fc receptor III (CD16)

Low affinity immunoglobulin gamma Fc receptor III, commonly known as CD16, is a critical mediator of the immune system that bridges the innate and adaptive immune responses by binding the Fc portion of IgG antibodies. It exists in two primary isoforms: CD16a (FCGR3A), a transmembrane receptor expressed on natural killer (NK) cells and macrophages, and CD16b (FCGR3B), a GPI-anchored protein found predominantly on neutrophils. CD16a is essential for antibody-dependent cellular cytotoxicity (ADCC), where it triggers the release of cytotoxic granules to destroy antibody-coated target cells, such as those infected by viruses or malignant tumor cells. In clinical practice, CD16 is a primary effector for many therapeutic monoclonal antibodies, and its activity is significantly influenced by genetic polymorphisms, most notably the V158F variant, which affects binding affinity and treatment efficacy. Beyond oncology, CD16 is involved in the clearance of immune complexes and has been implicated in the pathogenesis of autoimmune and infectious diseases.

Other names

CD16FCGR3CD16aCD16bFCGR3AFCGR3BFc gamma RIIIIgG Fc receptor IIIFcR-10

Binding to the Fc region of IgG antibodies to activate antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP).