Cytoskeletal rearrangements in response to adhesion to dmA1A2 VWF and fibronectin under shear flow. Platelets were allowed to interact with dmA1A2 VWF alone or together with FN as described in Figure 4. Cells were fixed after 2 minutes of flow, stained for αIIb, imaged by deconvolution microscopy, and scored for filopodial extensions. (A) ADAP^+/+ or (B) ADAP^−/− platelets adherent on the combined A1A2 VWF/FN surface. Arrowheads illustrate filopodia, which were shorter and less numerous in panel B. (C) Quantitative representation of the percentage of cells with filopodial protrusions on dmA1A2 VWF alone or together with FN ± SEM (*P < .05). Results shown are the summary of 3 separate experiments.