Figure 2.

Micropatterned surface (A) of fibrillar collagen can be patterned along with a contact activator (kaolin in blue, left) or an extrinsic activator (lipidated TF in white, right). The fluorescently labeled kaolin particles were visualized (A, left) (15), while FITC-annexin V allowed staining of sorbed lipidated TF at increasing concentrations (A, right). The amount of TF (or kaolin) and the amount of CTI are shown schematically (A, arrows) to illustrate different experimental conditions to modulate the amount of contact pathway and extrinsic pathway triggering of clotting. In the absence of surface TF, without affecting platelet deposition (B), all the fibrin produced is the result of FXIa activity (C), which is blocked by 20 μg/mL of O1A6 or 14E11 at 100 s⁻¹ (14).