FIG. 6.

Effects of heat-inactivated NHS as a source of sCD14 on IL-8 induction in bladder epithelial cells by P. aeruginosa LPS (upper panels) or S. aureus PGN (lower panels). Cells were washed with PBS, cultured in a serum-free medium containing 5% BSA for 6 h, and then cultured in a medium with either 5% BSA (without NHS) (bars 1), 5% NHS (bars 2), or 5% CD14-depleted NHS (bars 3) for 6 h. The cultured cells were stimulated with 1 or 10 μg of P. aeruginosa LPS or S. aureus PGN/ml for 24 h. Concentrations of IL-8 in the culture supernatants were determined by ELISA. Significant differences (**, P < 0.01; *, P < 0.05) between the presence and absence of NHS are indicated. Each experiment was performed in triplicate.