Quantification of cytokines in supernatants from non differentiated and PMA-differentiated THP-1 cells.

Quantification of cytokines in supernatants from undifferentiated THP-1 cells and macrophages (differentiated THP-1 cells) stimulated with benzalkonium chloride (BAK), dinitrochlorobenzene (DNCB), lipopolysaccharide (LPS) or tumor necrosis factor alpha (TNF-α), and phosphate buffered saline (PBS) as a control. Results are expressed as a percentage of expression compared to the negative control ± standard deviation (SD). SD was not shown if <1. Results with statistical differences (P<0.05) compared to macrophages exposed to PBS are presented in bold.