NeuroRepair Department, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland.
Division of MR Research, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, USA.
Stem Cell Res Ther. 2019 Jun 25;10(1):187. doi: 10.1186/s13287-019-1296-8.
Mesenchymal stem cell (MSC) transplantation has been explored as a new clinical approach to repair injured tissues. However, in order to evaluate the therapeutic activity of MSC, cell tracking techniques are required to determine the fate of transplanted cells in both preclinical and clinical studies. In these aspects, different vital stains offer the potential for labeling and monitoring of grafted cells in vivo. It is desirable to have tracking agents which have long-term stability, are not toxic to the cells, and do not affect cell function.
Here, we selected three different labels: CellTracker™ Green CMFDA, eGFP-mRNA (genetic pre-tag), and Molday ION Rhodamine B™ (nanoparticle-based fluorescent and magnetic label) and performed extensive analysis of their influence on in vitro expansion of human bone marrow-derived mesenchymal stem cells (hBM-MSCs), as well as potential of affecting therapeutic activity and the impact on the durability of staining.
Our study showed that basic hBM-MSC characteristics and functions might be affected by labeling. We observed strong alterations of metabolic activity and morphology after eGFP and CellTracker™ Green CMFDA hBM-MSC staining. Molday ION Rhodamine B™ labeling revealed superior properties relatively to other vital stains. The relative expression level of most of the investigated growth factors remained stable after cell labeling, but we have observed some changes in the case of EGF, GDNF, HGF, and IGF gene expression.
Taken together, we suggest performing similar to ours extensive analysis prior to using any cell label to tag MSC in experiments, as it can thoroughly bias results.
间充质干细胞（MSC）移植已被探索作为修复受损组织的一种新的临床方法。然而，为了评估 MSC 的治疗活性，需要细胞跟踪技术来确定临床前和临床研究中移植细胞的命运。在这些方面，不同的活体染料为体内标记和监测移植细胞提供了潜力。理想的跟踪剂应具有长期稳定性、对细胞无毒、且不影响细胞功能。
在这里，我们选择了三种不同的标记物：CellTracker™ Green CMFDA、eGFP-mRNA（遗传预标记）和 Molday ION Rhodamine B™（基于纳米颗粒的荧光和磁性标记），并对它们对人骨髓间充质干细胞（hBM-MSCs）体外扩增的影响进行了广泛分析，以及对治疗活性的潜在影响和对染色耐久性的影响。
我们的研究表明，基本的 hBM-MSC 特征和功能可能会受到标记的影响。我们观察到 eGFP 和 CellTracker™ Green CMFDA hBM-MSC 染色后代谢活性和形态发生强烈改变。Molday ION Rhodamine B™ 标记与其他活体染料相比具有优越的特性。在细胞标记后，大多数研究的生长因子的相对表达水平保持稳定，但我们观察到在 EGF、GDNF、HGF 和 IGF 基因表达的情况下发生了一些变化。
综上所述，我们建议在实验中使用任何细胞标记物标记 MSC 之前，像我们这样进行广泛的分析，因为它会严重影响结果。
