ApoA-I requires lipid to prevent VWF self-association under shear stress. Purified VWF (7 μg/mL) was added to LRA-treated plasma with 10 mM EDTA and sheared at 2400 rpm for 90 minutes at 37°C. The VWF remaining in solution after exposure to shear stress was expressed as a percentage of VWF solution in parallel samples not exposed to shear. (A) Purified VWF in LRA-treated plasma was sheared in the presence of increasing concentrations of HDL or ApoA-I. (B) Purified VWF in LRA-treated plasma was sheared in the presence of buffer (10 mM HEPES, 25 mM NaCl, 10 mM EDTA, pH 7.5), desalted serum-free medium (SFM), LRA-treated SFM, purified ApoA-I (500 μg/mL), and combinations of these reagents. (C) Purified VWF in LRA-treated plasma was sheared in the presence of boiled plasma proteins (500 μg/mL) before or after treatment with LRA. (D) SDS-gradient polyacrylamide gel electrophoresis (4% to 15%) and Gelcode blue stain (Thermo Scientific) of boiled plasma (15 μg protein) and boiled plasma after treatment with LRA (8 μg protein).