TABLE 2.

Pilus-deficient P. aeruginosa PAK mutants fail to induce significant apoptosis of human Chang conjunctiva epithelial cellsa

P. aeruginosa strain% Annexin-positive cellsb% Cells with low Δψmc% Cells with high ROSd
Without infection6.0 ± 3.02.5 ± 1.56.6 ± 3.3
PAO-I35.1 ± 7.9e35.3 ± 8.4e41.5 ± 8.6e
PAK39.1 ± 11.0e37.0 ± 11.4e25.6 ± 5.6e
PAKΔpilA7.4 ± 4.74.1 ± 2.010.4 ± 5.1
PAK Δpilall6.6 ± 3.54.4 ± 3.36.8 ± 2.2
  • a Chang conjunctiva epithelial cells were infected with for 3 h with the P. aeruginosa strains as indicated. Data are means ± standard deviations of 3 experiments.

  • b Apoptotic cell death was then determined by FACS analysis of FITC-annexin V-stained cells. Values represent percentages of FITC-annexin-positive cells.

  • c Mitochondrial membrane potential was determined by FACS analysis of JC1-stained cells. Values represent percentages of cells with low Δψm.

  • d Synthesis of ROS was determined by FACS analysis of DHE-stained cells. Values indicate percentages of ethidium-positive cells with high ROS production.

  • e Significantly different from value for uninfected control cells (P < 0.05) as calculated by Student's t test.