Figure 3. The DNA damage sensor, RAD50, is induced in particulate matter (PM)-stimulated macrophages. (A) Bone marrow–derived macrophages (BMDMs) were treated with PM (100 μg·mL-1) for 24 hours, then were stained with RAD50. Quantification of RAD50-positive cells for a dose response of PM. (B) Western blot analysis for a dose response (various concentrations of PM for 24 hours) of RAD50 protein expression in BMDMs treated with PM. (C) Quantification of pATM-positive cells in BMDMs treated with PM at 100 μg·mL-1 for 24 hours. All experiments were repeated at least 3 times, and data are presented as means ± SEMs. *p < 0.05; **p < 0.01; ***p < 0.001.