Anti-CD55, clone F4-29D9

1 mg/ml in sterile PBS, BSA free, sodium azide free. Recognizes a single chain glycoprotein of 70kDa, identified as CD55 (also known as decay accelerating factor, DAF). This mAb was clustered in Kobe at the Sixth International Workshop on Human Leukocyte Differentiation Antigens as F429D-9 (N-L120). CD55/DAF is widely expressed on cells throughout the body including leukocytes, erythrocytes, epithelium, endothelium, and fibroblasts. It is a Glycosyl phosphatidylinositol anchored (GPI-anchored) member of the membrane bound complement regulatory proteins that inhibit autologous complement cascade activation. It prevents the amplification steps of the complement cascade by interfering with the assembly of the C3-convertases, C4b2a and C3bBb, and the C5-convertase, C4b2a3b and C3bBb3b. CD55 also serves as receptor for CD97 and for echovirus and Coxsackie B virus. Anti-CD55 can be used as marker for paroxysmal nocturnal hemoglobinuria (PNH). 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. [The UniProt Consortium]