FIG. 2.

P. aeruginosa but not L. pneumophila stimulated CCL20 production by human CBMC (a) and the human mast cell line HMC-1 (b). Human mast cells (10⁶ cells/ml) were stimulated with P. aeruginosa (CF-associated mucoid strain 8821 and nonmucoid strain PAO.1), L. pneumophila (cell-to-bacteria ratio, 1/50), or LPS (from P. aeruginosa serotype 10; Sigma) (10 μg/ml) for 24 h. CCL20 levels in cell-free supernatants were determined by ELISA. Results are means ± standard errors of the means from eight individual donors (a) and from four independent experiments (b).