IκBα dose-dependently modulated the inflammatory response to acute pneumonia-induced ALI. Overexpression of IκBα attenuated the increase in BAL interleukin-1β (A), but did not alter BAL TNF-α (B), or interleukin-6 concentrations (C), after Escherichia coli-induced ALI. IκBα dose dependently decreased BAL CINC-1 (D), did not alter BAL IL-10 concentrations (E), and dose dependently decreased BAL KGF concentrations (F). These effects were greatest with the highest IκBα (5 × 1010 particles) dose. The gray bars represent sham (uninfected) animals. Vehicle, animals that received intratracheal vehicle alone; IκBα 5 × 109, animals that received 5 × 109 AAV6 particles encoding IκBα; IκBα 1 × 1010, animals that received 1 × 1010 AAV6 particles encoding IκBα; IκBα 5 × 1010, animals that received 5 × 10109 AAV6 particles encoding IκBα, BAL, bronchoalveolar lavage; IL-1β, interleukin-1β; TNF-α, tumor necrosis factor-α; CINC-1, cytokine-induced neutrophil chemoattractant-1; KGF, keratinocyte growth factor. Significantly different from vehicle group (P < 0.05, ANOVA).