Background

Vascular thrombosis is a major clinical problem. Timely lysis and/or removal of blood clots to rapidly re-establish blood flow is critical to treat thrombotic diseases, such as ischemic stroke, myocardial infarction and pulmonary embolism.

Intravenous infusion of a fibrinolytic agent, such as tissue plasminogen activator (tPA) is one of the clinical strategies. This converts plasminogen to plasmin and thus triggers fibrin lysis. Unfortunately, tPA has an extremely short half-life (2-6 min) it is rapidly inactivated by circulating inhibitors such as plasminogen activator inhibitor I (PAI I). Therefore, large doses of tPA are required for effective thrombolysis which leads to bleeding complications.