Additional file 4: Figure S3. of Multi-walled carbon nanotube induces nitrative DNA damage in human lung epithelial cells via HMGB1-RAGE interaction and Toll-like receptor 9 activation

DNA damage in CNT-S-treated cells. (A) Immunofluorescent images of 8-nitroG formation in CNT-S-treated A549 cells. A549 cells were incubated with CNT-S at indicated concentrations for 8 h at 37 °C, and 8-nitroG formation was examined by immunofluorescent technique as described in Methods. Hoechst, Hoechst 33258. Magnification, X200. (B) Relative staining intensity of 8-nitroG formed in CNT-S-treated A549 cells. Staining intensity per cell was analyzed by an ImageJ software. Relative staining intensity of the control was set at 1. Data represent means ± SD of 3 or 4 independent experiments. ***p < 0.001, compared with the control. (C) 8-NitroG formation in CNT-S-treated HBEpC cells. HBEpC cells were treated with CNT-S at indicated concentrations for 4 h at 37 °C, and immunofluorescent technique was performed. Magnification, X100. (D) Relative staining intensity of 8-nitroG formed in CNT-S-treated HBEpC cells. Staining intensity was analyzed as described in (B). Data represent means ± SD of 3 or 4 independent experiments. ***p < 0.001, compared with the control. Statistical analysis was performed by ANOVA followed by Tukey’s test. (TIF 654 kb