Figure 6.

Hemostatic activity associated to intraplatelet rFVIIa. A and B: Experiments were performed by adding 30% of platelets previously incubated with PBS or with 6 μg/mL rFVIIa to blood samples. Platelets were washed to remove excess rFVIIa before being added to the perfusates. Images are representative fields of perfusion studies in microchambers using collagen surfaces with flowing blood from healthy donors containing platelets previously incubated with PBS (A) or with rFVIIa (B). C–F: Studies were performed with damaged vascular vessels adding platelets from healthy donors (C) or patients with severe FVII deficiency (E) incubated with PBS (D) or platelets incubated with rFVIIa (F). Perfused surfaces were washed, fixed and processed histologically. Micrographs were obtained in the bright field mode; original magnification, ×400. p, platelet interaction; f, fibrin mesh.