Fig. 5. Effects of Fusobacterium nucleatum and Streptococcus pneumoniae on the production of proinflammatory cytokines in vivo. Mice (n = 6) were treated with heat-inactivated F. nucleatum (1 × 10⁸ CFU/mouse), heat-inactivated S. pneumoniae (1 × 10⁸ CFU/mouse), or live S. pneumoniae (1 × 10⁸ CFU/mouse) for 2 h. KC and IL-6 protein levels in the lungs (a), trachea (b), and serum (c) were determined using ELISA and expressed as pg/mg protein or pg/ml. Data are presented as the mean ± SD.