Soft culture substrates favor stem-like cellular phenotype and facilitate reprogramming of human mesenchymal stem/stromal cells (hMSCs) through mechanotransduction
Soft culture substrates favor stem-like cellular phenotype and facilitate reprogramming of human mesenchymal stem/stromal cells (hMSCs) through mechanotransduction
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DOI：
10.1038/s41598-019-45352-3
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发表时间：
2019-06-24
影响因子：
4.6
通讯作者：
Graos, Mario
中科院分区：
文献类型：
--
作者：
Gerardo, Heloisa;Lima, Ana;Graos, Mario
生物物理线索影响细胞行为的许多方面。细胞外基质的硬度由细胞探测，并通过机械转导蛋白网络转导成生化信号，强烈影响干细胞的行为。细胞的干性与细胞的机械性质密切相关，如细胞内收缩性和刚度，而这些又受到微环境的影响。多能性与柔软和低收缩性细胞有关。因此，我们假设软的细胞培养基质，可能诱导低细胞收缩性和刚度，增加间充质干细胞/基质细胞（MSC）重编程为诱导多能干细胞（iPSC）的效率。我们证明，软基板（1.5或15千帕聚二甲基硅氧烷- PDMS）引起的几个细胞功能的MSC到一个表型更接近多能干细胞（PSC）的调制。在软基质上培养的MSC呈现出更松弛的细胞核，更低的粘着斑和F-actin组装成熟度，更多的常染色质和更少的异染色质核DNA区域，以及多能性相关基因的表达增加。这些变化与MSC的重编程相关，对集落形成的动力学、稳健性和重编程效率具有积极影响。此外，基质硬度影响iPS细胞和集落的几个表型特征，并且数据表明软基质有利于完全iPSC重编程。
Biophysical cues influence many aspects of cell behavior. Stiffness of the extracellular matrix is probed by cells and transduced into biochemical signals through mechanotransduction protein networks, strongly influencing stem cell behavior. Cellular stemness is intimately related with mechanical properties of the cell, like intracellular contractility and stiffness, which in turn are influenced by the microenvironment. Pluripotency is associated with soft and low-contractility cells. Hence, we postulated that soft cell culture substrates, presumably inducing low cellular contractility and stiffness, increase the reprogramming efficiency of mesenchymal stem/stromal cells (MSCs) into induced pluripotent stem cells (iPSCs). We demonstrate that soft substrates (1.5 or 15 kPa polydimethylsiloxane - PDMS) caused modulation of several cellular features of MSCs into a phenotype closer to pluripotent stem cells (PSCs). MSCs cultured on soft substrates presented more relaxed nuclei, lower maturation of focal adhesions and F-actin assembling, more euchromatic and less heterochromatic nuclear DNA regions, and increased expression of pluripotency-related genes. These changes correlate with the reprogramming of MSCs, with a positive impact on the kinetics, robustness of colony formation and reprogramming efficiency. Additionally, substrate stiffness influences several phenotypic features of iPS cells and colonies, and data indicates that soft substrates favor full iPSC reprogramming.