Figure 4.

Restoration of thrombus formation in factor-deficient mice by supplementation of factor VIII or IX. Blood from F8^−/− or F9^−/− mice was pre-incubated for 10 min with recombinant human FVIII or FIX (2 U/mL), respectively. Samples were perfused for 4 min over collagen at a shear rate of 1000 s⁻¹, as described for Figure 1. Thrombi were then stained with FITC-annexin A5. (A) Representative microscopic phase contrast images (bars, 50 μm). (B) Surface area covered by platelet-fibrin thrombi and PS-exposing platelets. Mean ± SEM; n = 3.