Sulfur mustard induces apoptosis and necrosis in SCL II cells in vitro

Sulfur mustard (bis(2-chloroethyl) sulfide, HD) is an alkylating agent caus ing erythema and blistering with a latency of several hours after skin expo sure. In the present in vitro study the influence of HD (1 muM-1 mM for 30 min or 4 h) on the viability and growth of SCL II cells was investigated, N o significant differences in cytotoxicity were observed as assessed by form azan formation from XTT tetrazolium salt at 24, 48 and 72 h after exposure. Sulfur mustard concentrations of >500 muM were associated with an increasi ng portion of apoptotic cells without change in necrosis rate as assessed b y nuclear morphology and gel electrophoresis of the DNA. The ATP levels wer e not affected up to 6h after HD exposure (less than or equal to 1 mM). Twe lve hours later, ATP depletion was observed at HD concentrations of >500 mu M, Colony-forming ability was impaired at concentrations of <1 mu-M. Cell g rowth studies in comparison with nuclear morphology indicated late apoptoti c death predominating at lower concentrations of HD. In summary, the data show that HD may inhibit cell growth already at concen trations where viability parameters and cell metabolism are not yet affecte d. Copyright (C) 2000 John Wiley & Sons, Ltd.