COMPLEMENT AND ALLERGOLOGY

Complement contributes to the body's innate defences against infectiou s agents. It is composed of proteases which, one after the other, are able to activate the subsequent fraction resulting in the formation of the final lytic complex which acts on the cell membrane of microorgan isms. Clinicians must take the complement system into account, as cert ain deficiencies of one of its fractions: :can lead to clinical pictur es similar to those encountered during a hypersensitivity reaction. Pr eliminary observations also suggest that the complement system is invo lved in certain authentic anaphylactic reactions.