C1 inhibitor provided protective effects in myocardial cell injury (137) , transplantation (138) and various other diseases (139) . C1-INH was effective in a randomized, double-blind clinical study in septic intensive care unit patients. Whereas the renal dysfunction was reduced, the mortality rate remained unchanged in both groups (140) . The only clinical application for C1 inhibitor so far is for C1 inhibitor deficiency leading to hereditary angioedema (141) .