Milestones in the development of tissue-type plasminogen activator (t-PA) as a fibrin-specific thrombolytic agent include: purification of human t-PA from the culture fluid of the Bowes melanoma cell line, elucidation of the molecular basis of fibrin-specific plasminogen activation, first experimental animal models of thrombosis, first patient (renal allograft) treated with melanoma t-PA, pilot...