Fc γ RIIb/CD16-2 (2.4G2) Antibody: sc-18867

Fc γ RIIb/CD16-2 Background Information
CD32 (designated Fc © RIIb in mouse) is a low affinity receptor for the Fc fragment of aggregated IgG. CD32 is responsible for the clearance of immunocomplexes by macrophages and also plays an important role in the regulation of antibody production by B cells. IgG can noncooperatively bind either one or two highly glycosylated CD32 molecules, and this binding delivers a negative signal for B cells. CD32 exists as several isoforms that are produced by alternative splicing of three distinct genes, A, B, and C. These isoforms are designated Fc © RIIa, Fc © RIIb, Fc © RIIb3, and Fc © RIIc. All isoforms are present on monocytes, placental trophoblasts and endothelial cells. In addition, the FcgRIIb forms are present on B lymphocytes, and the FcgRIIa and FcgRIIc forms are found on neutrophils. CD16 (designated CD16-2 in mouse), the low affinity Fc gamma receptor III for IgG (Fc © RIII), exists both as a polypeptide-anchored form (Fc © RIIIA or CD16-A) in human natural killer cells and macrophages and as a glycosylphosphatidylinositol-anchored form (Fc©RIIIB or CD16-B) in neutrophils. CD16-A requires association of the © subunit of FcéRI or the Ω subunit of the TCR-CD3 complex for cell surface expression. CD16-B is polymorphic; the two alleles are termed NA1 and NA2 . CD16 is one of only four eukaryotic receptors known to exist natively in both the transmembrane (TM, CD16-A) and glycosylphosphatidylinositol (GPI, CD16-B) isoforms.