FIG. 3.

VacA inhibits G₁-to-S cell cycle progression. (A) Primary human CD4⁺ T cells were activated with CD3/CD28 antibodies in the presence of the indicated additives. Cells were then harvested 24, 48, and 72 h postactivation, and cell cycle analysis was performed using propidium iodide staining as described in Materials and Methods. The combined percentages of cells in S and G₂/M are indicated. (B) Cells from panel A were harvested at 48 h postactivation for immunoblot analysis as described in Materials and Methods. Protein lysates were generated and immunoblotted with the indicated antibodies. Immunoblotting with antibody against total p19 was used as a loading control. Results are representative of three independent experiments.