Anti-Hu CD89 APC Mab (A59)

Specificity: The mouse monoclonal antibody A59 recognizes an extracellular epitope of CD89, a 55-100 kDa glycoprotein serving as a receptor for IgA and expressed mainly on granulocytes, monocytes and macrophages. CD89 (Fc-alpha-R) is a type I transmembrane glycoprotein serving as a receptor for IgA. Soluble CD89 is detectable in serum and retains its IgA binding capacity. For signal transduction the association with FcR gamma chain homodimers is needed. CD89 is expressed on granulocytes, monocytes, macrophages, dendritic cells and myeloid cell lines. Its expression is upregulated in presence of IgA immune complexes, stimulators (such as LPS, PMA), TNF alpha, IL1 beta or GM-CSF, and it is downregulated in presence of TGF beta and suramin. Binding of IgA-opsonized targets to CD89 leads to phagocytic and cytotoxic processes of the immunologic defense.