Depletion of intracellular cholesterol abolished apical sorting of ADAMTS13. MDCK cells expressing full-length ADAMTS13 were treated without (control) or with a combination of lovastatin (L, 40 μg/mL) and methyl-β-cyclodextrin (CD, 250 μg/mL) for 48 hours. The conditioned media on both apical and basolateral domains were collected and analyzed by Western blotting with anti–V5 IgG and SuperSignal ECL system (A). The total volume of the conditioned medium loaded into the gel from the treated group (L + CD) was twice as much as that from the control. The percentage of ADAMTS13 detected in the apical domain of MDCK cells was quantified by densitometry with NIH ImageJ software (B). The entries represent mean ± SD (n = 3) in panel B. The integrity of the tight junction of MDCK cells prior to (control) and after drug treatment (L + CD) is shown in panel C.