Binding of FVIII, VWF, and FIX to recombinant sLDLR^CR1-7. (A) Immobilized purified recombinant sLDLR^CR1-7 (0.5 μg/well) was incubated with purified FVIII (•) (0-500 nM), VWF (○) (0-500 nM), or FIX (▪) (0-500 nM). Bound FVIII, VWF, or FIX was detected by incubation with peroxidase-conjugated monoclonal antibodies CLB-CAg 12, CLB-RAg 56, and CLB-FIX 11, respectively. (B) Immobilized purified recombinant sLDLR^CR1-7 (0.5 μg/well) was incubated with purified FVIII (150 nM) in the absence or presence of increasing concentrations of recombinant RAP (0-3 μM). (C) Immobilized purified recombinant LRP cluster 2 (0.5 μg/well) was incubated with FVIII (20 nM) in the absence or presence of increasing concentrations of LRP cluster 2 (○) (0-0.5 μM) or sLDLR^CR1-7 (•) (0-4 μM). Residual FVIII binding was detected as described. Data represent the mean ± SD of 3 separate experiments.