Fig. (6).

Cleavage of Serp-1 by thrombin in the presence of heparin. (A) The experimental conditions were identical to those in Fig. 5. Lanes 1 to 7 contained 1 µg Serp-1 and 0.03 NIH units thrombin. Lane 8 contained 1 µg Serp-1. Prior to adding thrombin into the reaction, heparin was incubated with Serp-1 at room temperature for 30 minutes. Lane 1, 0 IU heparin; lane 2, 0.0001 IU heparin; lane 3, 0.001 IU heparin; lane 4, 0.005 IU heparin; lane 5, 0.01 IU heparin; lane 6, 0.05 IU heparin; lane 7, 0.1 IU heparin. (B). Protein band density was scanned by the Gel-doc system (Bio-Rad) and plotted as a function of heparin units.