Miller R Tyler
University of Texas, Southwestern Medical School, Dallas VAMC, Dallas, TX, USA..
Matrix Biol. 2017 Jan;57-58:366-373. doi: 10.1016/j.matbio.2016.07.001. Epub 2016 Jul 17.
Physical properties are differentiated characteristics of tissues that are essential to their function. For example, the function of bone depends on its rigidity, and the function of skin depends on its elasticity. The aggregate physical properties of tissues are determined by a collaborative relationship between their cells and matrix and are the product of genetic programs, circulating chemical signals, physical signals, and age. The mechanical properties of matrix and basement membranes in biologic systems are difficult to understand in detail because of their complexity and technical limitations of measurements. Matrix may contain fibrillary collagens, network collagens, other fibrillar proteins such as elastin, fibronectin, and laminins, proteoglycans, and can be a reservoir for growth factors. In each tissue and in different regions of the same tissue, matrix composition can vary. The goal of measuring the mechanical properties of matrix is to understand the physical environment experienced by specific cell types to be able to control cell behavior in vivo and for tissue engineering. At this time, such precise analysis is not possible. The general elastic properties of tissues are now better characterized, and model systems using limited numbers of matrix constituents permit improved understanding of the physical behavior of matrix and its effects on cells. This review will describe model systems for understanding problems of matrix elasticity, focus on a relatively new aspect of matrix mechanics, strain-stiffening, and the interactions of cells with matrix to produce overall tissue mechanical properties.
物理性质是组织的不同特征，对其功能至关重要。例如，骨骼的功能取决于其刚性，皮肤的功能取决于其弹性。组织的总体物理性质由其细胞与基质之间的协同关系决定，是遗传程序、循环化学信号、物理信号和年龄的产物。由于生物系统中基质和基底膜的复杂性以及测量的技术局限性，很难详细了解它们的力学性质。基质可能包含纤维状胶原蛋白、网络状胶原蛋白、其他纤维状蛋白质（如弹性蛋白、纤连蛋白和层粘连蛋白）、蛋白聚糖，并且可以是生长因子的储存库。在每个组织以及同一组织的不同区域，基质组成可能会有所不同。测量基质力学性质的目的是了解特定细胞类型所经历的物理环境，以便能够在体内控制细胞行为并用于组织工程。目前，这种精确分析是不可能的。现在对组织的一般弹性性质有了更好的表征，使用有限数量基质成分的模型系统有助于更好地理解基质的物理行为及其对细胞的影响。本综述将描述用于理解基质弹性问题的模型系统，重点关注基质力学的一个相对较新的方面，即应变硬化，以及细胞与基质的相互作用以产生整体组织力学性质。
