Figure 2

Colonization levels in the upper airways of mice inoculated with S. pneumoniae . (A) Mice were exposed to CS or air as indicated and intranasally inoculated with S. pneumoniae (S.p.). Colonization densities were determined by quantitative cultures of upper airway lavages 4 days (3 months CS) and 7 days (7 months CS) postinoculation. (B) Numbers of viable S.p. were determined in lung tissue (homogenate). Bars indicate significant differences of *p < 0.05 and **p < 0.01, n ≥ 5 per group.