Complement is a complex system containing more than 30 various glycoproteins present in serum in the form of components, factors, or other regulators and/or on the surface of different cells in the form of receptors. It is a highly sophisticated host defence system designed to destroy pathogens. Once the complement system is activated, a chain of reactions involving proteolysis and assembly occurs, resulting in destruction of the membranes of pathogens. The cascade up to the cleavage of C3 (Complement component 3), which plays a...