Complement-mediated acinar cell necroses in pancreatitis induced by basement membrane antibodies.

To study the role of the serum complement system in the early necrosis of acinar cells an acute pancreatitis was produced by injection of basement membrane antibodies into the pancreatic duct of mice and rats. In all animals deposition of complement (C3) and antibasement membrane IgG could be observed in an identical position within areas of acinar cell necrosis. The extent of parenchymal damage and the intensity of complement deposits corresponded to the injected dose of antibodies. The importance of cytolytically active complement components (C5-9) was demonstrated in congenitally C5-defective old line mice which did not show typical centrolobular necroses 1 hr after intraductal injection of antibodies. However, the normocomplementemic mice developed extensive necroses of acinar cells. The results support the hypothesis of a complement-induced acinar cell necrosis in acute pancreatitis.