FIGURE 1.

Modification of lysine residues on BDD-fVIII abolishes its binding to LRP1. A, microtiter wells were coated with BDD-fVIII (5 μg/ml) and then incubated with (Modified) or without (Unmodified) EZ-Link sulfo-NHS-biotin. Following incubation, the wells were incubated with streptavidin-alkaline phosphatase to confirm that BDD-fVIII was modified. B, following modification, wells were incubated with fVIII monoclonal antibody ESH8 to confirm even coating of fVIII. C, increasing concentrations of purified LRP1 were incubated with microtiter wells coated with BDD-fVIII (squares) or BDD-fVIII modified by sulfo-NHS-biotin (circles). Following washing, the amount of LRP1 bound was measured using anti-LRP1 monoclonal antibody 8G1. The experiments were repeated twice, and representative experiments are shown. Error bars represent S.E.