Fig. 5.

Pseudomonas aeruginosa exoenzyme Y (ExoY) induces extracellular active caspase-7 independent of caspase-3. Wild-type (WT), caspase-3-deficient (C3KO), and caspase-7-deficient (C7KO) pulmonary microvascular endothelial cells (PMVECs) were infected with either PA103 (4 h on WT and C3KO, 2.5 h on C7KO) or ExoY⁺ (6 h on WT and C3KO, 4 h on C7KO). Caspase-3/7 activity was assessed in supernatants. RFU, relative fluorescent units. Data were analyzed by 2-way ANOVA with Tukey’s multiple-comparison test. Interaction was significant (P = 0.0004), row factor (infection condition) was significant (P < 0.0001), and column factor (cell type) was significant (P = 0.0122). *P < 0.0001; #P = 0.0023, NS, not significantly different from control, n = 5. Each symbol represents a single experiment performed in duplicate.