THE SERUM COMPLEMENT-SYSTEM

The human complement system, one of the protein cascade systems in pla sma, is essential for immune defence. Its contribution to the host's d efence is permanent and available even before specific antibodies and T-lymphocytes are generated in the early stage of infection. Complemen t is activated tither by the classical or the alternative pathways, bo th of them leading to a cascade-like reaction sequence. Besides its fu nction in host defence, complement is important in immune complex regu lation. In addition, complement serves as a key mediator of the inflam matory response. Specific receptors on almost every cell including mas t cells (anaphylatoxin receptors) provide the base for a variety of ef fector functions mediated by complement-derived activation products. O f clinical relevance are complement deficiencies as well as the comple ment-mediated inflammatory tissue destruction. A modern comprehensive diagnosis is essential for a now available complement-oriented antiphl ogistic therapy.