[The so-called "contact" system of plasma: consequences of the activation of the Hageman factor]

The contact system of plasma includes 4 zymogens, Hageman factor, pre-kallikrein, factor XI and plasminogen, and a cofactor, the high molecular weight kininogen (HMWK). The activation of the contact system leads to the production of bradykinin, blood coagulation, fibrinolysis, complement activation and neutrophil stimulation. Consequently these phenomena generate a lot of pro-inflammatory factors which contribute to the local and systemic inflammatory processes.