Figure 2.

Determination of cell survival, apoptosis, and oxidative DNA damage in lung epithelial cells exposed to hyperoxia, radiation, and double-hit combination challenge. Non-tumorigenic murine alveolar type II epithelial cells (C10) were evaluated after 1 and 2 cycles of hyperoxia and radiation exposure for (a) cell survival using light microscopy (200×); (b) apoptotic bodies using fluorescent DAPI staining; and (c) DNA damage by comet assay analysis. Data are presented as mean ± SEM. * p < 0.05 for each exposure condition as it compares with the unexposed control (CTL) in the same respective time-group; ^# p < 0.05 for significant differences between O₂-alone compared to O₂ + IR; ^§ p < 0.05 for significant differences between IR-alone compared to O₂ + IR.