Parameters of FITC dextran accumulation in day-6 CD1a-DC precursors and day-11 CD14-derived DCs. (A) MFI of histograms shown in Fig 3. The background fluorescence (cells pulsed at 4°C) was subtracted. (B and C) Cells were pulsed with 0.1 mg/mL FITC dextran at 37°C for various times, washed with cold medium, and analyzed on a FACScan. Uptake of FITC dextran was performed at day 6 on total population by double color fluorescence using, after pulse with FITC dextran, anti-CD1a–PE (CD1a⁺ cells), anti-CD14–PE (CD14⁺ cells), and anti-CD1a–PE plus anti-CD14–PE (CD14⁻CD1a⁻ cells; B). Uptake of FITC dextran was performed at day 11 by single color fluorescence on the sorted populations (C). (D and E) Cells were pulsed with 0.1 mg/mL FITC dextran for 15 minutes at 37°C, washed with cold medium, and analyzed immediately or after culture at 37°C for various times in marker-free medium. Chase was performed at day 6 on total populations by double color fluorescence (D). Chase was performed at day 11 by single color fluorescence on the sorted populations (E). Results of each panel are representative of three experiments or more.