Factor H Antibody (Monoclonal - #1)

Factor H is a fluid phase complement regulatory protein consisting of a single peptide chain of 20 short consensus repeat segments or CCP’s with a molecular weight of approximately 155 KD. Factor H regulates the alternative pathway of the complement system by modifying activity of the “feedback loop.” It does this in three ways. First, it is a co-factor for the serine protease Factor I, which cleaves C3b to iC3b. iC3b has no hemolytic or amplification function, but may be bound by complement receptors. Second, Factor H prevents the formation of and accelerates the disassociation of the alternative pathway C3 convertase, C3bBb from cell surfaces. Finally, Factor H binds to polyanions on host cell surfaces and tissue matrices, such as basement membranes, blocking deposition of C3b. This later activity is leveraged by many pathogens as a mode of complement evasion. Recent studies have linked Factor H to hemolytic uremia syndrome (HUS), age-related macular degeneration (AMD), and membrano-proliferative glomerulonephritis. Factor H may also be elevated in certain cancers, including bladder cancer, potentially as a protective measure used by tumor cells to evade complement attack.