Recombinant human protein was used as the immunogen for the CD32 antibody.
This CD32 antibody binds most strongly to the IIa isoforms of CD32 (FcRII), 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.
