A theoretically-motivated biaxial tissue culture system with intravital microscopy
A theoretically-motivated biaxial tissue culture system with intravital microscopy
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DOI：
10.1007/s10237-007-0099-5
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发表时间：
2008-08-01
影响因子：
3.5
通讯作者：
Yeh, A. T.
中科院分区：
文献类型：
--
作者：
Humphrey, J. D.;Wells, P. B.;Yeh, A. T.
许多细胞类型在不同的刺激（包括机械负荷）下产生、重塑和降解细胞外基质。胶原蛋白是许多组织中细胞外基质的主要结构成分，关于胶原蛋白沉积和降解的分子生物学和生物化学已知很多，但相关的机械生物学模型却很少。例如，我们没有定量描述或规则，作为改变机械负荷的功能，胶原蛋白周转的动力学，我们不知道是什么决定了新纤维在现有组织中结合的方向和预拉伸。在本文中，我们使用约束混合理论来研究平面软组织的生长和重塑，以激发一种新的实验方法来研究相互竞争的假设，例如，合成细胞如何排列新的胶原蛋白。特别是，由于应力和应变场在双轴测试组织的中心区域可以是均匀的，并且因为双轴测试允许不同的方案，其中在不相等的应变存在时可以施加相等的应力，或者在没有应变的情况下可以保持应力，我们报告了说明双轴培养研究潜在效用的模拟。最后，我们描述了计算机控制系统的相关设计，该系统允许在天然组织适应或组织工程等效物发展的各个阶段对胶原密度、取向和交联进行活体显微定量，每个阶段都受到良好控制的双轴载荷。
Many cell types produce, remodel, and degrade extracellular matrix in response to diverse stimuli, including mechanical loads. Much is known about the molecular biology and biochemistry of the deposition and degradation of collagen, the primary structural constituent of the extracellular matrix in many tissues, yet there has been little modeling of the associated mechanobiology. For example, we do not have quantitative descriptions, or rules, for the kinetics of collagen turnover as a function of altered mechanical loading and we do not know what governs the orientation and pre-stretch at which new fibers are incorporated within extant tissue. In this paper, we use a constrained mixture theory for growth and remodeling of planar soft tissues to motivate a new experimental approach for investigating competing hypotheses on, for example, how new collagen is aligned by synthetic cells. In particular, because stress and strain fields can be homogeneous in a central region of a biaxially tested tissue, and because biaxial testing admits diverse protocols wherein equal stresses can be imposed in the presence of unequal strains or stresses can be maintained in the absence of strain, we report simulations that illustrate the potential utility of biaxial culture studies. Finally, we describe the associated design of a computer-controlled system that allows intravital microscopic quantification of collagen density, orientation, and cross-linking at various stages during the adaptation of a native tissue or the development of a tissue engineered equivalent, each subjected to well controlled biaxial loads.