Sander Leonard M
Randall Laboratory, Department of Physics, University of Michigan, Ann Arbor, MI 48109, USA.
J Biomech Eng. 2013 Jul 1;135(7):71006. doi: 10.1115/1.4024199.
Cells imbedded in biopolymer gels are important components of tissue engineering models and cancer tumor microenvironments. In both these cases, contraction of cells attached to the gel is an important phenomenon, and the nonlinear nature of most biopolymers (such as collagen) makes understanding the mechanics of the contraction a challenging problem. Here, we investigate a unique feature of such systems: a point source of contraction leads to substantial deformation of the environment, but large strains and large alignment of the fibers of the gel are confined to a small region surrounding the source. For fibroblasts in collagen-I, we estimate that the radius of this region is of order 90 μ. We investigate this idea using continuum estimates and a finite element code, and we point out experimental manifestations of the effect.
嵌入生物聚合物凝胶中的细胞是组织工程模型和癌症肿瘤微环境的重要组成部分。在这两种情况下，附着在凝胶上的细胞收缩都是一个重要现象，而大多数生物聚合物（如胶原蛋白）的非线性特性使得理解收缩力学成为一个具有挑战性的问题。在这里，我们研究了此类系统的一个独特特征：收缩点源会导致环境发生显著变形，但凝胶纤维的大应变和大排列局限于源周围的一个小区域。对于I型胶原蛋白中的成纤维细胞，我们估计该区域的半径约为90微米。我们使用连续介质估计和有限元代码来研究这一观点，并指出该效应的实验表现。
