Fig. 4.
Effect of F(ab′)2 fragments of MoAb 724 on shear-independent platelet aggregation induced by different ristocetin concentrations. Washed platelets (108/mL) and purified vWF (10 μg/mL) were incubated with different ristocetin concentrations either in the absence (•) or in the presence of F(ab′)2 fragments (10 μg/mL) of MoAb 724 (▪). Slopes of aggregation were measured and results were expressed relative to the value obtained with 1 mg/mL ristocetin concentration in the absence of MoAb 724, which was arbitrarily set as the maximal aggregation. At low ristocetin concentrations (0.5 to 0.8 mg/mL), F(ab′)2 fragments of 724 increased the aggregation.
