Description
The C1 inhibitor, a plasma protease, regulates the activation of the C1 complex. This inhibitor forms a stoichiometric complex with the C1r or C1s proteases, rendering them proteolytically inactive. It plays a potentially crucial role in modulating key physiological pathways, such as complement activation, blood coagulation, fibrinolysis, and kinin generation. The C1 inhibitor is highly effective against FXIIa and can also inhibit chymotrypsin and kallikrein. In mice, its primary function involves regulating various plasma cascade systems, including the complement, coagulation, fibrinolytic, contact, and kallikrein systems