Binding of ADAMTS13 to MR and DC-SIGN. ADAMTS13 was immobilized on microtiter plates. Increasing concentrations (0-10 μg/mL) of recombinant MR CTLD 4-7-Fc (A) or DC-SIGN-Fc (B) chimeras were added to the wells. To determine whether ADAMTS13 binding to these receptors is specific, the Fc-chimera receptors were pre-incubated with mannan prior to being added to the wells. Data are from 2 independent experiments. (C-D) iDCs were pre-incubated at 37°C in normal medium or in medium containing different concentrations of anti-MR Ab (C) or anti–DC-SIGN blocking Ab AZND1 (D) for 20 minutes, and then 50nM ADAMTS13-488 was added to the cells. Uptake was measured after 45 minutes by FACS and is expressed as a percentage of uptake. Graphs represent data from 3 independent experiments and are expressed as means ± SD.