Figure 1
From: The role of complement in the pathogenesis of renal ischemia-reperfusion injury and fibrosis
Overview of the complement system. Activation of the complement system by the classical, lectin, and alternative pathways results in cleavage of the C3 and C5 fractions by the C3 and C5 convertases, which, in turn, generate the opsonin C3b, anaphylatoxins C3a and C5a, and the membrane-attack complex (MAC; C5b–C9). Regulation of complement activation and deposition is controlled by fluid-phase (C4BP, Factor H, and C1-INH) and membrane-bound regulators (CD35, CD46, CD55, and CD59).