FIG. 5.
B cells and T cells enter the cell cycle in response to stimulation by P. aeruginosa exoenzyme S. Splenocytes (4 × 105/well) were cultured with medium alone (open bars) or 5 μg of exoenzyme S per ml (solid bars) for 3 days. Cells were labeled with either anti-Thy 1.(T cells), anti-B220 (B cells), or no antibody (T and B cells) and analyzed for DNA content by propidium iodide labeling with flow cytometry. The percentage of cells in the cell cycle was determined by CellQuest analysis. The bars represent the mean percentage of cells in the cycle ± SEM from five different experiments. *, P < 0.05 compared to the corresponding unstimulated group.