. Author manuscript; available in PMC: 2019 May 13.
Published in final edited form as: Cytotherapy. 2019 Mar 14;21(5):546–560. doi: 10.1016/j.jcyt.2018.12.005
This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/)