Why Did The Complement System Cause The Killing And Opsonization Of

Many years ago, Jules Bordet discovered the complement as a heat-labile component of normal plasma which caused the killing and opsonisation of bacteria. This activity of killing and opsonisation of bacteria were to complement the antibacterial activity of antibody. The complement system was a group of more than 20 serum glycoprotein which had been synthesized by the liver that were secreted by hepatocytes and circulating in the tissue fluids and in the blood. Also most of the proteins that formed the complement were inactive; however they were activated in an enzyme cascade sequence. The complement system was first evolved as a part of the innate immune system and played vital role. The proteases in the system cleaved exact proteins which would release cytokines and an amplifying cascade of the further cleavages were initiated. The activation of the cell killing membrane attack complex and the massive amplification of the response were the last result of the activation cascade. (Janeway et al, 2011)
Classical pathway, alternative pathway and lectin pathway were the three different pathways that activated the complement system. Those pathways could cause the activation of C3; cleaving C3 to produce of C3b.C3b was large fragments that act as an opsonin and C3a which was a small fragment that promote inflammation. The lytic pathway that could break some bacteria and the plasma membranes cells could be trigger by activated C3. This process would produce C5a.(Min Chen,