Invitrogen™ CD16 Monoclonal Antibody (3G8), APC

CD16, known as Fc gamma receptor III, exists in two distinct isoforms: Fc gamma RIIIA and Fc gamma RIIIB. These isoforms are encoded by the genes FCGR3A and FCGR3B, respectively, which are located on chromosome 1 and share a high degree of similarity. Fc gamma RIIIA is expressed as a polypeptide-anchored form on monocytes, macrophages, and lymphocytes such as natural killer (NK) cells, but not on T or B cells. This receptor recognizes the Fc portion of immunoglobulin G (IgG) and is involved in the clearance of immune complexes from circulation. Upon binding IgG, Fc gamma RIIIA activates signal transduction pathways that result in antibody-dependent cell-mediated cytotoxicity (ADCC), phagocytosis, cytokine release, and antigen presentation. Fc gamma RIIIB is expressed on polymorphonuclear neutrophils (PMN) as a glycosylphosphatidylinositol (GPI)-anchored form. It plays a role in similar immune functions, including cellular-mediated cytotoxicity and enhancement of virus infections. Mutations in the FCGR3A gene have been associated with Immunodeficiency 20 and linked to susceptibility to recurrent viral infections, systemic lupus erythematosus, and alloimmune neonatal neutropenia. Alternatively spliced transcript variants encoding different isoforms have been identified for this gene. Diseases associated with FCGR3A include Immunodeficiency 20 and Herpes Zoster.