Fig. 1. Effects of human oral bacteria on IL-8 and IL-6 production by human bronchial epithelial cells. BEAS-2B cells were treated with or without indicated heat-inactivated oral bacteria at a bacterial density equivalent to 1 × 10⁸ CFU/ml for 12 h, after which IL-8 and IL-6 protein levels in the cell culture supernatants were determined using ELISA and expressed as pg/ml. Data are presented as the mean ± SD.