Physiological and pathological role of factor XII

Introduction. The most widely accepted notion of the function blood clotting factor XII (FXII, Hageman factor) is its involvement in internal pathway. However, biological role FXII diverse. Aim – to review diverse functions FXII. Main findings. a serine protease. structure has high degree homology with plasminogen, tissue plasminogen activator and urokinase activator. Activated (FXIIa) five substrates: high-molecular kininogen, precallikrein, FXI, complement proteins (C1s, C1r). provides hemostatic balance by participating processes fibrinolysis. regulates inflammatory allergic reactions interacting kallikreinkinin system system. activity various cells vivo: endotheliocytes, platelets, monocytes, neutrophils, fi broblasts, dendritic cells, which determines physiological pathological processes.