Morphology and FITC-dextran uptake of 3d mDC and 7d mDC. The size and the morphology of immature and mature 3d DC and 7d DC were analyzed by (A) flow cytometry and (B) light microscopy. (C) DC were incubated without or with 10 μg/ml FITC-dextran at 37°C or at 4°C for 1 hour. The cells were then washed three times in ice-cold PBS with 1% FCS. The uptake of FITC-dextran was analyzed by flow cytometry. Data are representative for three independent experiments. The left-most open histograms represent medium only controls, the open grey curves indicate mDC incubated with FITC-Dextran at 4°C and the filled histograms at 37°C.