Figure 3.

Effects of TAT-SOD₁on cell viability after X-ray irradiation. HaCaT cells were pretreated with PBS, SOD₁ or TAT-SOD₁ for 5 h, respectively. Then, cells were incubated for 48 h. Cell viabilities were determined by with a colorimetric assay using CCK-8. (A) Compared with PBS treatment cells, SOD₁ treatment cells showed no significant difference on cell viability. (B) TAT-SOD₁ treatment cells significantly increased cell viability after X-ray irradiation. *P < 0.05 and **P < 0.01, compared with ionizing radiation alone treated cells. These results are representative of at least three separate experiments.