COMPLEMENT AND BIOCOMPATIBILITY

Blood contact with foreign surfaces induces a certain degree of activa tion of the defence systems including complement. Recent data using co mplement specific inhibitors have shown that complement is not only as sociated with, but in fact contributes to the whole body inflammatory reaction seen as a complication of cardiopulmonary bypass (artificial surfaces) and is responsible for the hyperacute rejection of xenograft s (foreign endothelium). Complement activation products, particularly the terminal SC5b-9 complex (TCC), is a sensitive indicator of bioinco mpatibility. Modifications of the artificial surfaces by coating with heparin improves both coagulation and complement compatibility. The us e of specific complement inhibitors in general improves biocompatibili ty both of artificial materials and foreign endothelium.