Analysis of monocyte cultures in the presence of GM-CSF plus IL-4 or M-CSF. Density plots show the CD11c versus MHC II, F4/80 versus Ly-6C, and the control background staining profiles of monocytes cultured with GM-CSF plus IL-4 or M-CSF for 24 hours, and the CD11c versus MHC II profiles of monocytes cultured with GM-CSF plus IL-4 or M-CSF for 3 or 7 days in the presence or absence of LPS. The percentages of MHC II^int and MHC II^hi DCs (solid-line boxes) and monocytes/macrophages (dashed-line ovals) are indicated. Macrophages present in day-7 cultures with GM-CSF plus IL-4 (dashed-line ovals in panel A) were gated out in panel B on the basis of their autofluorescence in the FL3 channel of the flow cytometer (CD11c and MHC II expression was analyzed in the FL1 and FL2 channels, respectively). Data are representative of 4 experiments with similar results.