Dose-dependent effects of A. baumannii OMVs on the BAL concentrations of chemokines and cytokines. Mice were intranasally introduced to A. baumannii OMVs (0, 1, and 5 μg in total protein amounts), and at 24 h after intranasal instillation of the OMVs, the BAL concentrations of chemokines and cytokines were determined. The BAL concentrations of chemokines CCL2 (A) and CXCL1 (B) as well as cytokines IL-6 (C), TNF-α (D), IFN-γ (E), and IL-1β (F) were measured. *, P < 0.05; **, P < 0.01.