Fig 1: Antioxidants reduced the karyotypically abnormal iPS cell clones. a, b Immunostaining of γH2AX during reprogramming. Cells at day 4 of transfection with KMOS mRNAs were stained and 100 cells of each condition were counted for γH2AX-positive foci. c Schematic diagram of the RNA-based reprogramming regimen with NAC added throughout the reprogramming. d The percentage of karyotypically abnormal iPS cell clones in reprogramming cultures treated with NAC or not. e, f Western blotting and quantitative analysis of DNA Ligase IV in a series of different time points during the reprogramming process. g, h Western blotting and quantitative analysis of Rad51 in a series of different time points during the reprogramming process. i, j Western blotting and quantitative analysis of Rad52 in a series of different time points during the reprogramming process. k The schematic protocol depicts NAC treatments at different time points during RNA-based reprogramming. l Quantification of the percentage of karyotypically abnormal iPS cell clones in reprogramming cultures treated with NAC at different time periods. Statistical analyses are presented as Mean ± SD, n = 3. *P < 0.05, **P < 0.01. Scale bar: 20 µm