Anti-Human MASP-3 Monoclonal Antibody (clone 38:12-3) -10 mg (CAT#: CB-P472-K) Datasheet

Antibody

Monoclonal antibody 38:12-3 recognizes MASP-3, a 94 kDa mannan-binding lectin (MBL)-related serine protease. Three pathways of complement activation have been reported: antibody-dependent classical pathway, antibody-independent alternative pathway and lectin pathway. The activation of each pathway involves the formation of a serine protease complex, which leads to the activation of the central complement component C3. In the lectin pathway, mannose-binding lectin (MBL)-related serine protease (MASP) forms a complex with oligolectin molecules, and the latter is involved in pattern recognition. After the recognition molecule binds to carbohydrates on the surface of the microorganism, MASP is converted to its active form and initiates complement activation. Six members of the MASP-like serine protease family have been reported: MASP-1, MASP-2, MASP-3, Map19, C1r and C1s. These products show the same domain organization, even though the total amino acid sequence identity is only about 40%. Each MASP type forms a homodimer and binds to MBL and fibrin respectively in a Ca2+ dependent manner. The four MBL-related proteins are produced by only two genes. The MASP-1/3 gene encodes MASP-1 and MASP-3, while the MASP-2/Map19 gene produces MASP-2 and non-enzymatic MASP-2 MAP19. MASP-1 preferentially associates with the oligomer MBL (called MBL-1), while MASP-2 and MASP-3 mainly associate with the larger MBL oligomers (MBL II and MBL III). MASP-3 is produced by alternative splicing of the MASP-1/3 gene. The MASP-3 transcript is composed of the A chain shared by MASP-1 and MASP-3 and the unique B chain of MASP-3. The biological function of MASP-3 remains unclear. However, it was found that MASP-3 down-regulated the C4 and C2 lytic activity of MASP-2. MASP-3 inhibits MASP-2 by competitively inhibiting the binding of MASP-2 and MBL and inhibiting the activation of MASP-2 associated with MBL. Monoclonal antibody 38:12-3 cannot recognize MASP-1.