Anti-CD55/DAF Monoclonal Recombinant Antibody

CD55 is a 60-70 kD glycosylphosphatidylinositol (GPI)-anchored single chain glycoprotein also known as decay-accelerating factor (DAF). It is expressed on hematopoietic cells including erythrocytes and many non-hematopoietic cells. CD55 accelerates the dissociation of the components of the C3-convertases (namely C2a from C4b in the C4bC2a complex, a C3-convertase of the classical pathway, and factor Bb from the C3bBb complex, a C3-convertase of the alternative pathway) to protect cells from inappropriate damage caused by autologous complement. CD55 has been reported to reduce the efficiency of NK cell lysis and induce signal transduction in T cells. CD55 has also been shown to interact with CD97 and bind to Coxsackie and Echovirus. Protein function: This protein recognizes C4b and C3b fragments that condense with cell-surface hydroxyl or amino groups when nascent C4b and C3b are locally generated during C4 and c3 activation. Interaction of daf with cell-associated C4b and C3b polypeptides interferes with their ability to catalyze the conversion of C2 and factor B to enzymatically active C2a and Bb and thereby prevents the formation of C4b2a and C3bBb, the amplification convertases of the complement cascade (PubMed:7525274). Inhibits complement activation by destabilizing and preventing the formation of C3 and C5 convertases, which prevents complement damage (PubMed:28657829). [The UniProt Consortium]