High OCT4 and Low Expressions Determine In Vitro Lifespan of Mesenchymal Stem Cells

Figure 3

Low protein expression as a robust early marker of BM-MSC lifespan. The protein expression levels of (a) , (b) , (c) SOD2, and (d) in early passage cells from each donor were analyzed by western blot. Band intensities were densitometrically evaluated and bar graphs on the left represent the densitometric values of , , SOD2, and normalized to the loading control (β-actin). Normalized expression values were then plotted against the final PD number and statistically analyzed by Spearman correlation, as shown in the graphs on the right. The expression levels of protein in early passage cells were inversely correlated with lifespan. Results are representative of three independent experiments, with similar results.

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