Effects of TFPI binding to fibrin clot by C-terminal basic peptide (A) or Gly 212-Phe 243 peptide in the K3 domain (B) of TFPI. Various concentrations of each peptide were mixed with fibrinogen, and radiolabeled TFPI was added. Fibrin was formed by the addition of 2 μg/mL of thrombin. After 15 minutes, fibrin was removed and washed by TBS. The radioactivity of the supernatant and the washed fibrin was then measured. Each bar represents the mean ± SD from four samples. (□), Supernatant; (▪), fibrin clot.