Release of IL-8, PGE2 and LTB4 by bronchial epithelial spheroids in function of LPS dose and time. (A,B,C) BES from non-COPD (open bars) and COPD smokers (filled bars) were exposed to various concentrations of LPS for 24 h. Data are expressed as fold increase of IL-8, PGE2 and LTB4 by comparison to basal levels. The findings are illustrative of 5 independent experiments. (D,E,F) LPS treatment (10 μg/ml) of COPD and non-COPD smokers BES for 1, 4, 8 and 24 h. Data of IL-8, PGE2 and LTB4 protein levels are expressed in pg.mg total protein-1. The findings are illustrative of 4 independent experiments.