This MAb reacts with a CD32 (FcgRII) epitope (cluster-4). It displays a stronger reaction with Daudi than with U937 cells. The epitope is located in domain 2 of FcgRIIa. Its Fab'2 fragments block immune complex binding. CD32 (FcgRII) is a type 1 transmembrane glycoprotein that mediates several functions including phagocytosis, cytotoxicity, and immunomodulation as well as platelet aggregation. Three genes (A, B, and C) encode CD32 and at least 6 isoforms are generated via alternative mRNA splicing, i.e., IIa1, IIa2, IIb1, IIb2, IIb3 and IIc. Monocytes/macrophages, placental trophoblasts and endothelial cells express all isoforms. In addition, the IIb isoform is expressed by B cells, and the IIa isoform by platelets, granulocytes and, weakly, by B cells. NK cells and neutrophils express Isoform IIc. CD32 binds weakly to the Fc region of monomeric IgG but more strongly to IgG aggregates and immune complexes.Primary antibodies are available purified, or with a selection of fluor