Amplification of surface TF by circulating 100 fM TF requires flow. The effect of exogenously added lipidated TF (100 fM) was studied in the presence and absence of venous wall shear rate of 100 s⁻¹. Immunostaining for platelet GPIbα and fibrin(ogen) after 5-minute whole blood perfusion (with or without 100 fM TF) over TF titration arrays (A). Column averages of fluorescent intensity of the GPIbα staining (top) and fibrin(ogen) staining (bottom) are plotted against the TF surface concentration for static (dashed line) or venous (solid line) flow for perfusion of CTI whole blood without (○) or with (●) 100 fM added lipidated TF for 3 independent experiments (3 × 30 spots per plotted data point) (B).