The C (Complement) system consists of about twenty plasma proteins that function either as enzymes or as binding proteins. In addition to these plasma proteins, the complement system includes multiple distinct cell-surface receptors that exhibit specifici ...ty for the physiological fragments of complement proteins and that occur on inflammatory cells and cells of the immune system. Activation of the complement system initiates a series of enzymatic reactions in which the proteolytic cleavage and activation of successive complement proteins leads to the covalent bonding or fixing of complement fragments to the pathogen surface. A major consequence of this is the uptake and destruction of complement coated microbes by phagocytes that bear receptors for these complement fragments. The complement system uses three different strategies for recognizing microorganisms, each of which initiates a pathway of complement activation that leads to the covalent bonding of complement proteins to microbial surfaces. These initiation pathways include: the Classical, the Lectin, and the Alternative pathway.
View More... View Less...