Department of Chemical and Biomolecular Engineering, School of Science and Engineering, Tulane University, 6823 Saint Charles Ave., Boggs Center Room 300, New Orleans, LA, 70118, USA.
Center for Stem Cell Research and Regenerative Medicine, School of Medicine, Tulane University, New Orleans, LA, USA.
Stem Cell Res Ther. 2020 Jul 16;11(1):292. doi: 10.1186/s13287-020-01805-5.
Colony-forming efficiency is a time-honored metric of the proliferation potential of mesenchymal stem cells (MSCs). This commentary raises a concern about the practice of using colony-forming efficiency as a proxy for cell survival. A recently published study from my laboratory investigated this issue. A marker of cellular aging, CD264, was employed to separate human bone marrow MSCs into populations of CD264 cells and culture-matched, aging CD264 cells with high and low colony-forming efficiency, respectively. In vitro cell survival was evaluated with a single-cell assay; in vivo survival by bioluminescence imaging of MSCs attached to scaffolds that were implanted ectopically in immunodeficient mice. In our study, in vitro and in vivo survival of the MSC populations was independent of colony-forming efficiency. This finding indicates that caution should be exercised before using colony-forming efficiency as an indirect metric of cell survival. Direct measurement of survival may be required. Awareness of this issue should foster a robust experimental design and, thereby, facilitate the translation of MSC research into clinical practice.
集落形成效率是衡量间充质干细胞（MSCs）增殖潜力的一个久经考验的指标。这篇评论就将集落形成效率用作细胞存活的替代指标这一做法提出了担忧。我的实验室最近进行了一项研究，探讨了这个问题。我们使用一种细胞衰老标志物 CD264，将人骨髓间充质干细胞分为 CD264 细胞群和培养匹配的、衰老的 CD264 细胞群，后者的集落形成效率分别较高和较低。我们通过单细胞分析评估了体外细胞存活情况；通过生物发光成像评估了附着在支架上的 MSCs 在免疫缺陷小鼠异位植入后的体内存活情况。在我们的研究中，MSC 群体的体外和体内存活与集落形成效率无关。这一发现表明，在将集落形成效率用作细胞存活的间接指标之前，应谨慎行事。可能需要直接测量存活情况。对这一问题的认识应促进稳健的实验设计，从而有助于将间充质干细胞研究转化为临床实践。
