Fig. 4.
Inhibition of factor VII-activating protease (FSAP) activity by tissue factor pathway inhibitor (TFPI), TFPI-160, TFPI-K1M, and TFPI-K2M. Increasing concentrations of TFPI, TFPI-160 (A), TFPI-K1M or TFPI-K2M (B) were added to the chromogenic substrate S2288 (1 mm). Purified two-chain (tcFSAP) (10 nm) was added, and the absorbance at 405 nm was measured. Data are plotted as Vi/Vo against the inhibitor concentration. Vi and Vo indicate the velocities of substrate hydrolysis by 10 nm tcFSAP in the presence and absence of inhibitor, respectively. Results are given as mean ± standard error of the mean (n = 3).