Das Ankita, Adhikary Shreya, Chowdhury Amit Roy, Barui Ananya
Centre for Healthcare Science and Technology, IIEST, Shibpur, Howrah, West Bengal 711103, India.
Biomed Mater. 2021 Mar 3;16(3):034102. doi: 10.1088/1748-605X/abce4e.
Stem-cell (SC) chirality or left-right (LR) asymmetry is an essential attribute, observed during tissue regeneration. The ability to control the LR orientation of cells by biophysical manipulation is a promising approach for recapitulating their inherent function. Despite remarkable progress in tissue engineering, the development of LR chirality in SCs has been largely unexplored. Here, we demonstrate the role of substrate stiffness on the LR asymmetry of cultured mesenchymal stem cells (MSCs). We found that MSCs acquired higher asymmetricity when cultured on stiffer PCL/collagen matrices. To confirm cellular asymmetry, different parameters such as the aspect ratio, orientation angle and intensity of polarized proteins (Par) were investigated. The results showed a significant (p < 0.01) difference in the average orientation angle, the cellular aspect ratio, and the expression of actin and Par proteins in MSCs cultured on matrices with different stiffnesses. Furthermore, a Gaussian support-vector machine was applied to classify cells cultured on both (2% and 10% PCL/Collagen) matrices, with a resulting accuracy of 96.2%. To the best of our knowledge, this study is the first that interrelates and quantifies MSC asymmetricity with matrix properties using a simple 2D model.
干细胞（SC）的手性或左右（LR）不对称是组织再生过程中观察到的一个基本属性。通过生物物理操作来控制细胞LR方向的能力是重现其固有功能的一种有前景的方法。尽管组织工程取得了显著进展，但干细胞中LR手性的发展在很大程度上仍未得到探索。在此，我们展示了底物硬度对培养的间充质干细胞（MSC）LR不对称性的作用。我们发现，当在更硬的聚己内酯/胶原蛋白基质上培养时，间充质干细胞获得了更高的不对称性。为了确认细胞的不对称性，我们研究了不同参数，如长宽比、取向角和极化蛋白（Par）的强度。结果显示，在不同硬度基质上培养的间充质干细胞，其平均取向角、细胞长宽比以及肌动蛋白和Par蛋白的表达存在显著差异（p < 0.01）。此外，应用高斯支持向量机对在两种（2%和10%聚己内酯/胶原蛋白）基质上培养的细胞进行分类，准确率达到了96.2%。据我们所知，本研究首次使用简单的二维模型将间充质干细胞的不对称性与基质特性相互关联并进行量化。
