Deleterious effects of complement activation on the lungs during extracorporeal circulation and its inhibition by...

The purpose of this paper is to review the deleterious effects of complement activation during extracorporeal circulation on the lungs and to discuss the feasibility of FUT-175, a new synthetic protease inhibitor, as a complement activation inhibitor. Complement activation causes leukocyte aggregation and aggregated leukocytes behave as microemboli in the pulmonary vessels. Anaphylatoxins produced by complement activation have potent vasoactive properties and many chemical mediators are also released from leukocytes. FUT-175 might be effective to inhibit complement activation during cardiopulmonary bypass (CPB). Although deleterious effects of CPB on the lungs are multifactorial, we hypothesize that complement activation may play a major role in lung injury during CPB.