Complement C3 Proteins and Enzymes

The complement system, or complement cascade, is a part of the innate immune system that assists in defense against pathogens (1-3). Complement C3, also called C3 or C3 protein, is one of nine complement proteins and is the main component of the complement system which is composed of over 30 soluble and membrane-bound proteins (1,4). The complement cascade consists of three main pathways: the classical, the lectin, and the alternative, all of which converge into a common pathway involving C3 ...