TF binding of FVII variants. FVII (■), FVII_IX (●), FVII_X (▴), or FVII_X_HC (▵) was incubated with 4nM sTF for 5 minutes, followed by the addition of 10nM FVIIa and chromogenic substrate. The measured FVIIa:sTF amidolytic activity is shown. The decreased residual activity at higher FVII variant concentrations indicates that TF is increasingly occupied by FVII variant. R152A-FVII (*) produced by stably transfected baby hamster kidney cells was included as a reference.