Percentage of cytotoxicity of PMA differentiated THP-1 exposed to reagents.

Cell viability of PMA differentiated THP-1 was measured using an Annexin V/7-aminoactinomycin D (7-AAD) double staining in flow cytometry. We tested the 24 hours exposure to benzalkonium chloride (BAK), dinitrochlorobenzen (DNCB), lipopolysaccharide (LPS), tumor necrosis factor alpha (TNF-α) and phosphate buffered saline (PBS) for control. For each reagent, a panel of 4 different concentrations was tested. Grades of toxicity were separated in early apoptosis, late apoptosis, necrosis and total cytotoxicity. Results are expressed in percentage ± standard deviation (SD). Results with statistical differences (P<0.05) compared to PBS are presented in bold.