Fig. 5. Effect of leukotoxin (LTX) and leukotoxin diol (LTD) on cellular oxidative stress (DCFH oxidation) in endothelial cells. Cells were exposed to LTX and LTD (60 and 90 µM) for three hours. Fluorescence intensity was measured at an excitation wavelength of 490 nm and an emission wavelength of 525 ± 5 nm. Values are mean ± SEM of three separate experiments. *Significantly different from control values.