Effect of KM33_scFv and/or anti-C2 domain mAb BO2C11 on vesicles binding to immobilized factor VIII. Immobilized factor VIII was incubated with a molar excess of KM33_scFv and/or BO2C11. Various concentrations of vesicles containing 1% biotin-PE and either 15% Ptd-L-Ser (A) or 4% Ptd-L-Ser (B) were incubated with the immobilized complex of factor VIII with inhibitory antibodies. Data show factor VIII without inhibitory antibodies (■), in the presence of KM33_scFv (▲), in the presence of BO2C11 (♦), or both KM33_scFv BO2C11 (●). Each point represents the mean value ± SEM of 4 (A) or 3 (B) experiments.