Pulmonary cytokine levels after challenges with three serotypes of <i>M. catarrhalis</i>.

<p>Mice were vaccinated (1 dose per week, 4 doses in total) with either the adjuvant cholera toxin alone (1 µg/dose/mouse) or the combined conjugates AB or ABC (2.5 µg of each carbohydrate per dose per mouse) plus adjuvant. One week after the last booster, mice were challenged with aerosolized <i>M. catarrhalis</i> including 25238 (type A), O35E (type A), 26397 (type B), 26400 (type B), 26404 (type C), or 26391 (type C) (5×10⁸ to 1×10⁹ CFU/ml). At 6 h after the challenge, mouse lungs were harvested and homogenized for detection of IFN-γ, IL-12, IL-4, mKC, and TNF-α. Data are presented as mean ± SEM. *<i>P</i><0.05 indicates the significant difference vs adjuvant control by ANOVA. Note: Pulmonary IL-4 in mice immunized with adjuvant only was below the detection limit after <i>M. catarrhalis</i> 26391 challenge.