IMMUNOLOGY

Detailed explanation-1: -The C3 convertases formed by these early events of complement activation are bound covalently to the pathogen surface. Here they cleave C3 to generate large amounts of C3b, the main effector molecule of the complement system, and C3a, a peptide mediator of inflammation.

Detailed explanation-2: -At the basic level the broad functions of the complement system can be split into three areas: (1) the activation of inflammation; (2) the opsonization (labeling) of pathogens and cells for clearance/destruction; (3) the direct killing of target cells/microbes by lysis.

Detailed explanation-3: -Thus, one mechanism by which complement is regulated is by stimulating the dissociation of these complexes, and this is referred to as ‘decay acceleration’1, 2, 10). Another mechanism by which complement is regulated is the enzymatic inactivation of C4b and C3b, which are convertase components1, 2, 10).