Enhanced VWF fiber formation in the presence of an ADAMTS13 inhibitor and no effect of high LDL in patients with hypercholesterolemia on VWF cleavage by ADAMTS13. (A) Citrated plasma was incubated with inhibitory monoclonal antibody P3A11 (100 μg/mL) to ADAMTS13 or isotype control mouse antibody at room temperature for 1 hour before perfusion through microfluidic devices. VWF fiber formation was monitored and quantified over time. (B) VWF multimers in patients with hypercholesterolemia were similar to those of healthy controls. VWF multimers were analyzed using 1.7% agarose gel and immunoblotting. (C) VWF cleavages in vivo by ADAMTS13 measured by mass spectrometry in patients with hypercholesterolemia were similar to those in healthy controls. The data were analyzed using Student t test, and the P values are indicated. PNP, pooled normal plasma.