C1 inhibitor (C1-INH)

C1 inhibitor (C1-INH) is a serine protease inhibitor that inactivates several different proteases in the complement, contact, coagulation, and fibrinolytic systems. Though C1-INH has 478 residues (53kDa), the circulating protein is approximately 104 kDa by post-translational modification. Deficiency of C1-INH results in hereditary angioedema. In addition, C1– INH may prove useful in a variety of other diseases including septic shock, reperfusion injury, hyperacute transplant rejection, traumatic and hemorrhagic shock.