Effects of TAT-SOD
on 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.