*4.7. Statistical Analysis*

The data were analyzed using Student's *t*-tests and one-way analyses of variance (ANOVA) with GraphPad Prism software, and are presented as standard error of the mean (SEM), unless otherwise stated. Statistical significance was defined as \* *p* < 0.01, \*\* *p* < 0.05, # *p* < 0.001, and ## *p* < 0.005.

**Supplementary Materials:** The following are available online at http://www.mdpi.com/1660-3397/17/9/526/s1, Figure S1: Dose-dependent effect of Ech A or NAC on ex vivo expansion of PBMCs; Figure S2: Ech A recovered PB-CD34<sup>+</sup> cell expansion that was suppressed by H2O2 treatment; Figure S3: Each inhibitor was confirmed to work as expected; Figure S4: Raw data from immunoblotting experiments.

**Author Contributions:** Conceptualization, J.H. and J.-Y.J.; funding acquisition, J.-Y.J.; investigation, G.-B.P., M.-J.K., and H.S.L.; methodology, G.-B.P. and J.-Y.J.; resources, E.A.V., N.P.M., S.A.F., V.A.S., and J.H.; supervision, J.-Y.J.; writing—original draft, G.-B.P., D.K., and J.-Y.J.

**Funding:** This study was supported by the Korean National Research Foundation (KNRF) grants 2015M3A9B6073646, 2017M3A9G7072564 (both to J.Y.J.), and 2017K1A3A1A49070056 (to J.H.). The study was also supported by the Ministry of Education and Science of the Russian Federation (RFMEFI61317X0076).

**Conflicts of Interest:** The authors declare that they have no competing interests.
