ROLE OF COMPLEMENT IN GLOMERULAR INJURY

The alternative and classical pathway of activation enable the complem ent system to operate in various phases of infection. Both pathways ar e tightly controlled by membrane-bound and circulating regulatory prot eins. The immediate effects of complement activation comprise the dire ct lysis of target structures, the generation of proinflammatory molec ules and the recruitment of circulating leukocytes. In addition, compl ement is involved in antigen processing and in the regulation of appro priate immune responses. All functions of complement contribute to the development of glomerular injury The terminal membrane attack complex acts directly on resident glomerular cells, whereas the earlier compo nents are effective via the recruitment of leukocytes. That the early components are critically involved also in the metabolism and clearanc e of immune complexes is of special relevance to the pathogenesis of c ertain glomerular diseases. The exact role of complement components pr oduced locally by resident glomerular cells has yet to be determined.