Fig. 2. Fusobacterium nucleatum-induced mRNA (a, c) and protein (b, d) expression of proinflammatory cytokines by bronchial epithelial cells. BEAS-2B cells were treated with heat-inactivated F. nucleatum (1 × 108 CFU/ml) for the indicated times (a, b) and at different bacterial cell densities (1 × 106, 1 × 107, and 1 × 108 CFU/ml) after 3- (c) and 12-h exposures (d). The cells were harvested, and IL-8 and IL-6 mRNA levels were measured using real-time PCR with specific primers. The mRNA level was normalized to the GAPDH mRNA level and expressed as a fold increase. The IL-8 and IL-6 protein levels were determined using ELISA and expressed as pg/ml. Data are presented as the mean ± SD.
