Figure 2
Intracellular levels of O 2 -and GSH in cell lines before and after As 2 O 3 treatment. Intracellular levels of O2- and GSH were measured using CMFDA or DHE fluorescent probes and flow cytometry. (A) Untreated APL-derived NB4 cells and T-cell lines were examined for intrinsic levels of O2- production and GSH content. Histograms obtained with specific fluorescent probes (colored histograms) are overlaid on fluorescence histograms of unstained cells (black dotted histogram). A total of 20,000 events were analyzed for each histogram. Graphs report mean ± SE (n = 3 independent experiments) of integrated MFI values for O2- production and GSH content. The integrated MFI is calculated by multiplying the frequency of positive cells by the MFI of O2- and GSH. Asterisks denote statistically significant differences for levels of GSH or O2- between leukemic T-cell lines and APL-derived NB4 cells: *p ≤0.05; ***p ≤0.001. (B) O2- production and GSH content were examined in APL-derived NB4 cells and T-cell lines treated with 1 μM to 15 μM As2O3 for 24 h. Graphs report mean ± SE (n = 3 independent experiments) of integrated MFI values for O2- production and GSH content.