Defined Substrate by Aptamer Modification with the Balanced Properties of Selective Capture and Stemness Maintenance of Mesenchymal Stem Cells
Defined Substrate by Aptamer Modification with the Balanced Properties of Selective Capture and Stemness Maintenance of Mesenchymal Stem Cells
复制标题
通过适体修饰确定基质，具有间充质干细胞选择性捕获和干性维持的平衡特性
DOI：
10.1021/acsami.9b03333
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发表时间：
2019-04-24
影响因子：
9.5
通讯作者：
Gao, Changyou
中科院分区：
文献类型：
--
作者：
Wang, Xuemei;Zheng, Xiaowen;Gao, Changyou
内源性间充质干细胞（mesenchymal stem cells，MSCs）的募集作为一种诱人的原位组织再生方法，一直伴随着其他类型的细胞。因此，赋予基质选择性捕获MSC的性质具有巨大的价值。然而，据报道，当MSC在具有过度亲和性的基质上培养时，它们的干性减弱。因此，构建具有选择性捕获和干性保持平衡能力的基底成为一个很大的挑战。在这项研究中，通过将Apt19S接枝到聚乙二醇化的玻璃基底上来制造适体19S（Apt19S）修饰的基底。X射线光电子能谱结果证实，形成了聚乙二醇（PEG）层。椭圆偏振跟踪表明，PEG层的厚度随PEG浓度的增加而增加。石英晶体微天平的结果也验证了Apt19S的密度可以通过Apt19S溶液的浓度来调节。细胞粘附实验结果表明，Apt19S修饰后rBMSCs的粘附率和粘附面积明显增加。通过rBMSCs与巨噬细胞和NIH3T3细胞的共培养证实了选择性粘附，表明更高比例的rBMSCs粘附于Apt19S修饰的基底。通过模拟体液流动的流动模型进一步证实了特异性捕获的结果。逆转录聚合酶链反应、免疫荧光染色、增殖能力和分化能力的综合结果表明，在合适Apt19S浓度的基质上，rBMSCs的干细胞性保持较好。所有这些结果表明Apt19S修饰是赋予基质特异性捕获MSC能力的有效策略，并且可以通过精确调节适体密度来实现选择性捕获和干性维持之间的平衡。
The recruitment of endogenous mesenchymal stem cells (MSCs), as an alluring approach for in situ tissue regeneration, always accompanies with other types of cells. Therefore, it is of enormous value to bestow a substrate with the property of selective capture to MSCs. However, it was reported that when MSCs are cultured on a substrate with excessive affinity, their stemness diminished. Therefore, constructing a substrate with the balanced ability of selective capture and sternness maintenance becomes a big challenge. In this study, an Aptamer 19S (Apt19S)-modified substrate was fabricated by grafting Apt19S on a PEGylated glass substrate. The X-ray photoelectron spectroscopy results verified that the antifouling poly(ethylene glycol) (PEG) layer was created. Tracking by ellipsometry, the thicknesses of PEG layers were proved to increase with PEG concentration. The results of the quartz crystal microbalance also validated that the Apt19S densities could be modulated by the concentrations of the Apt19S solution. The results of the cell adhesion assay indicated that the modification of Apt19S caused a significant increase in the adhesion ratio and area of rBMSCs. Selective adhesion was confirmed by coculture of rBMSCs with macrophages and NIH3T3 cells, demonstrating that a higher proportion of rBMSCs adhered to the Apt19S-modified substrate. The results of specific capture were further confirmed by a flow model to simulate the body fluid flow. The comprehensive results of reverse transcription polymerase chain reaction, immunofluorescence staining, proliferation capacity, and differentiation assay showed that the sternness of rBMSCs was maintained better on a substrate with the appropriate Apt19S density. All of these results indicated that Apt19S modification is an effective strategy to endow a substrate with the specific capture ability of MSCs, and the balance between selective capture and sternness maintenance can be achieved by the precise regulation of the aptamer density.