CD11c⁺ DCs differentiate in the presence of IL-15 or IL-21. Murine BM cells were induced to differentiate to DCs by GMCSF alone (DCs; top row) or by addition of IL-15 (IL-15 DCs; middle row) or IL-21 (IL-21 DCs; bottom row) during the entire culture period of 8 days. Cells were analyzed by forward (FSC) and sideward (SSC) scatter (left column) and CD11c expression (middle column) using FACS analysis at day 8. The percentage of CD11c-expressing cells is shown in each panel in the middle column. One representative of 10 experiments is shown. Morphology was assessed by culturing the DCs for 48 hours on microchamber slides (right column) following Pappenheim staining. The scale bar is equal to 100 μm.