Effect of VWF mutants on the binding of ¹²⁵I-VWF to fibrin.¹²⁵I-WT-rVWF (250 ng/mL) and increasing concentrations of WT-rVWF (♦), ΔC1C2-rVWF (▴), ΔD4B-rVWF (□), and D1746G-rVWF (▵) were incubated on filters without and with fibrin (37 μg) for 2 hours at 37°C. For each point nonspecific binding (< 3% of total binding) was subtracted from the total binding to obtain the specific binding. Results are expressed as percentages of specific binding of ¹²⁵I-VWF in the absence of competitor. Error bars indicate SEM.