Institute for Biophysical Dynamics, University of Chicago, Chicago, IL 60637, USA.
Proc Natl Acad Sci U S A. 2011 Mar 22;108(12):4708-13. doi: 10.1073/pnas.1011123108. Epub 2011 Mar 7.
Cells in tissues are mechanically coupled both to the ECM and neighboring cells, but the coordination and interdependency of forces sustained at cell-ECM and cell-cell adhesions are unknown. In this paper, we demonstrate that the endogenous force sustained at the cell-cell contact between a pair of epithelial cells is approximately 100 nN, directed perpendicular to the cell-cell interface and concentrated at the contact edges. This force is stably maintained over time despite significant fluctuations in cell-cell contact length and cell morphology. A direct relationship between the total cellular traction force on the ECM and the endogenous cell-cell force exists, indicating that the cell-cell tension is a constant fraction of the cell-ECM traction. Thus, modulation of ECM properties that impact cell-ECM traction alters cell-cell tension. Finally, we show in a minimal model of a tissue that all cells experience similar forces from the surrounding microenvironment, despite differences in the extent of cell-ECM and cell-cell adhesion. This interdependence of cell-cell and cell-ECM forces has significant implications for the maintenance of the mechanical integrity of tissues, mechanotransduction, and tumor mechanobiology.
组织中的细胞与细胞外基质和相邻细胞都存在力学耦联，但细胞-细胞和细胞-细胞外基质黏附力的协调性和相互依赖性尚不清楚。在本文中，我们证明了一对上皮细胞之间细胞-细胞接触处维持的内源性力约为 100 nN，方向垂直于细胞-细胞界面，集中在接触边缘。尽管细胞-细胞接触长度和细胞形态有显著波动，该力仍能稳定维持。细胞在细胞外基质上的总牵引力与内源性细胞-细胞力之间存在直接关系，表明细胞-细胞张力是细胞-细胞外基质牵引力的恒定分数。因此，影响细胞-细胞外基质牵引力的细胞外基质特性的调节会改变细胞-细胞张力。最后，我们在组织的最小模型中表明，尽管细胞-细胞外基质和细胞-细胞黏附的程度存在差异，但所有细胞都从周围微环境中感受到相似的力。细胞-细胞和细胞-细胞外基质力的这种相互依赖性对组织的机械完整性、力学转导和肿瘤力学生物学的维持具有重要意义。
