Analysis of 4-hour monocyte cultures. Density plots show the CD11c versus MHC II profile of uncultured monocytes or monocytes cultured for 4 hours in the absence or presence of GM-CSF plus IL-4 or M-CSF. Some cultures with GM-CSF plus IL-4 were treated with the PI3K inhibitor Ly 294002. Gray profiles show the expression of the indicated markers by monocytes in each culture condition. The percentage of cells with a fluorescence intensity over the vertical lines, corresponding to the upper limit of control background staining (white profiles shown in the CD86 histograms), is indicated. Data are representative of 2 experiments with similar results.