Fig. 5

CD80 induction by oxidative stress is not a consequence of DNA damage response. (a) Immunofluorescence staining of γH2AX in CT26 cells after 24 h treatment with 5 mM Caffeine, 200 μM H₂O₂ or Caffeine+H₂O₂ together. Magnification: × 40. (b) Flow cytometry analysis of CT26 cells after 1 h of preincubation with 5 mM Caffeine and treatment with H₂O₂ (200 μM) for 24 h. (c) CT26 cells were transfected with control, ATM and ATR siRNAs. After 24 h, silencing efficiency was tested by RT Real Time PCR. (d) CT26 cells were transfected with control, ATM and ATR siRNAs. After 24 h, cells were treated with 200 μM H₂O₂ for 24 h before flow cytometry for CD80. (e) CT26 cells were transfected with control, ATM or ATR siRNAs. After 24 h, cells were treated with 200 μM H₂O₂ for 24 h before western blotting for ATM or ATR. (f) Representative staining of CT26 cells with the fluorogenic dye CM-H2DCFDA after 1 h of preincubation with 5 mM Caffeine and treatment with H₂O₂ (200 μM) for 1 h. Magnification: 40X. Mean ± S.E.M. of at least three independent experiments is indicated. n.s. not significant, *P < 0.05 ** P < 0.01 *** P < 0.001 by unpaired, two-tailed Student’s t-test