Substrate stiffness regulates extracellular matrix deposition by alveolar epithelial cells.
Substrate stiffness regulates extracellular matrix deposition by alveolar epithelial cells.
复制标题
DOI：
10.2147/rrb.s13178
复制
发表时间：
2011-01
期刊：
影响因子：
--
通讯作者：
Jones JC
中科院分区：
文献类型：
--
作者：
Eisenberg JL;Safi A;Wei X;Espinosa HD;Budinger GS;Takawira D;Hopkinson SB;Jones JC
该研究的目的是探讨肺纤维化模型--一种僵硬的底物是否导致肺泡上皮细胞(AEC)表型的改变，包括其细胞外基质(ECM)蛋白的沉积和组织。将新鲜分离的雄性SD大鼠肺AEC接种到不同硬度的聚丙烯酰胺凝胶基质上，用免疫印迹和共聚焦免疫荧光显微镜分析黏附、细胞骨架、分化和细胞外基质成分的表达和组织。我们观察到底物硬度影响细胞形态、局灶性粘连和肌动蛋白细胞骨架的组织。然而，令人惊讶的是，我们发现基质硬度对II型AEC向I型AEC的分化没有影响，也没有增加基质硬度导致上皮-间充质转化。相反，我们的数据表明，底物硬度调节血管内皮细胞α3层粘连蛋白亚单位的表达，以及纤维连接蛋白和层粘连蛋白在其细胞外基质中的组织。基质硬度的增加导致层粘连蛋白和纤维连接蛋白组装成纤维，这可能是纤维化肺的疾病表型之一。
The aim of the study was to address whether a stiff substrate, a model for pulmonary fibrosis, is responsible for inducing changes in the phenotype of alveolar epithelial cells (AEC) in the lung, including their deposition and organization of extracellular matrix (ECM) proteins. Freshly isolated lung AEC from male Sprague Dawley rats were seeded onto polyacrylamide gel substrates of varying stiffness and analyzed for expression and organization of adhesion, cytoskeletal, differentiation, and ECM components by Western immunoblotting and confocal immunofluorescence microscopy. We observed that substrate stiffness influences cell morphology and the organization of focal adhesions and the actin cytoskeleton. Surprisingly, however, we found that substrate stiffness has no influence on the differentiation of type II into type I AEC, nor does increased substrate stiffness lead to an epithelial–mesenchymal transition. In contrast, our data indicate that substrate stiffness regulates the expression of the α3 laminin subunit by AEC and the organization of both fibronectin and laminin in their ECM. An increase in substrate stiffness leads to enhanced laminin and fibronectin assembly into fibrils, which likely contributes to the disease phenotype in the fibrotic lung.