Department of Physics, Cavendish Laboratory, University of Cambridge, Cambridge, UK.
J Phys Condens Matter. 2010 May 19;22(19):194114. doi: 10.1088/0953-8984/22/19/194114. Epub 2010 Apr 26.
Cells are able to detect and respond to mechanical cues from their environment. Previous studies have investigated this mechanosensitivity on various cell types, including neural cells such as astrocytes. In this study, we have carefully optimized polyacrylamide gels, commonly used as compliant growth substrates, considering their homogeneity in surface topography, mechanical properties, and coating density, and identified several potential pitfalls for the purpose of mechanosensitivity studies. The resulting astrocyte response to growth on substrates with shear storage moduli of G' = 100 Pa and G' = 10 kPa was then evaluated as a function of coating density of poly-D-lysine using quantitative morphometric analysis. Astrocytes cultured on stiff substrates showed significantly increased perimeter, area, diameter, elongation, number of extremities and overall complexity if compared to those cultured on compliant substrates. A statistically significant difference in the overall morphological score was confirmed with an artificial intelligence-based shape analysis. The dependence of the cells' morphology on PDL coating density seemed to be weak compared to the effect of the substrate stiffness and was slightly biphasic, with a maximum at 10-100 µg ml(-1) PDL concentration. Our finding suggests that the compliance of the surrounding tissue in vivo may influence astrocyte morphology and behavior.
细胞能够检测和响应来自其环境的机械线索。以前的研究已经在各种细胞类型上研究了这种机械敏感性，包括神经细胞如星形胶质细胞。在这项研究中，我们仔细优化了聚丙酰胺凝胶，通常用作顺应性生长基质，考虑了其表面形貌、机械性能和涂层密度的均匀性，并确定了几个潜在的陷阱，用于机械敏感性研究。然后，使用定量形态计量分析，评估了星形胶质细胞在剪切储能模量 G'=100 Pa 和 G'=10 kPa 的基质上生长时对涂层密度聚-D-赖氨酸的反应。与在顺应性基质上培养的星形胶质细胞相比，在刚性基质上培养的星形胶质细胞的周长、面积、直径、伸长率、分支数和整体复杂度显著增加。基于人工智能的形状分析证实了整体形态评分存在统计学上的显著差异。与基质刚度的影响相比，细胞形态对 PDL 涂层密度的依赖性似乎较弱，并且呈轻微双相性，在 10-100 µg ml(-1)PDL 浓度下达到最大值。我们的发现表明，体内周围组织的顺应性可能会影响星形胶质细胞的形态和行为。
