The complement cascade is tightly regulated by short half-lives of its components and a series of endogenous regulatory proteins. Complement regulatory proteins counteract the complement activity and protect glomerular cells from injury (Nangaku 1998). In vitro, overexpression of CD59 protected cultured glomerular cells from attack (Nangaku et al. 1996). In the rat Heymann nephritis model, simultaneous blockade of complement regulatory proteins by neutralizing antibodies was required to develop proteinuria following injection of anti-megalin antibody (Schiller et al. 1998). Furthermore, genetic ablation of decay-accelerating factor (DAF) and CD59 aggravated tissue injury in anti-GBM
