Binding and uptake of NPs by human monocyte–derived DCs. NP uptake and binding was studied by incubating immature human monocyte–derived DCs with 100 μg/mL of targeted (NP-DC-SIGN-TLRL) and nontargeted (NP-Isotype-TLRL) NPs carrying TLRLs and a fluorescent dye. Binding was assessed after incubation on ice for 1 hour at 4°C (A), whereas uptake was studied by incubation for 1 hour (B) or 20 hours (C) at 37°C. Data from 1 representative experiment of 3 are shown.