Low affinity immunoglobulin gamma Fc region receptor II (CD32) (FcγRII)

Low affinity immunoglobulin gamma Fc region receptor II (FcγRII), commonly known as CD32, is a family of surface glycoproteins that bind the Fc portion of IgG antibodies [2, 13]. The family consists of activating isoforms (FcγRIIA and FcγRIIC) and an inhibitory isoform (FcγRIIB), which together regulate the threshold of immune cell activation [1, 9]. FcγRIIA is widely expressed on myeloid cells and platelets, where it triggers phagocytosis and inflammatory mediator release upon binding to immune complexes [2, 11]. In contrast, FcγRIIB is the only inhibitory Fc receptor and is primarily found on B cells and myeloid cells, serving to downregulate immune activation and maintain self-tolerance [1, 12]. Dysregulation of these receptors is implicated in the pathogenesis of autoimmune disorders such as systemic lupus erythematosus and in the progression of certain malignancies [2, 4, 9]. Therapeutic targeting of FcγRII involves monoclonal antibodies designed to either block activating signals or leverage inhibitory pathways to treat inflammation and cancer [1, 12].

Other names

CD32FCGR2Fc-gamma RIICDw32FCG2IGFR2

Modulation of immune cell activation through ITAM/ITIM signaling, inhibition of B-cell receptor signaling (FcγRIIB), enhancement of antibody-dependent cellular cytotoxicity (ADCC) through Fc engineering, and clearance of immune complexes [1, 9, 12, 15].