Mechanics of oriented electrospun nanofibrous scaffolds for annulus fibrosus tissue engineering
Mechanics of oriented electrospun nanofibrous scaffolds for annulus fibrosus tissue engineering
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DOI：
10.1002/jor.20384
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发表时间：
2007-08-01
影响因子：
2.8
通讯作者：
Mauck, Robert L.
中科院分区：
文献类型：
--
作者：
Nerurkar, Nandan L.;Elliott, Dawn M.;Mauck, Robert L.
设计椎间盘纤维环（AF）的功能性替代物取决于AF结构、组成和机械性能的重现。在这项研究中，我们提出了一个新的范式AF组织工程，侧重于重建解剖纤维结构，并使用本构模型来评估结构功能。一种改进的静电纺丝技术被用来产生对齐的纳米纤维聚合物支架工程AF的基本功能单元，一个单一的薄片。支架在多个纤维方向上进行单轴拉伸试验，证明模量对纤维角度的非线性依赖性，模拟了天然AF的非线性和各向异性。以前应用于天然AF的均匀化模型成功地描述了支架的机械响应，参数研究表明，非纤维基质，沿着纤维连接，是工程化AF的拉伸力学的关键贡献者。我们证明了AF细胞沿着对齐的支架和存款矩阵，有助于在与体内环境相关的负载条件下构建力学自身沿着定向。均质化模型应用于细胞接种的结构，并提供定量措施的基质和纤维间相互作用的演变。最后，该模型表明，在AF的纤维角度（28度-44度）下，工程材料的行为与天然组织非常相似，表明工程结构复制了单个AF板的生理行为。本构建模为分析工程化AF新生组织和天然AF组织提供了强大的工具，突出了功能性AF组织工程的关键机械设计标准。(C)2007骨科研究学会。出版社：Wiley Periodicals，Inc.
Engineering a functional replacement for the annulus fibrosus (AF) of the intervertebral disc is contingent upon recapitulation of AF structure, composition, and mechanical properties. In this study, we propose a new paradigm for AF tissue engineering that focuses on the reconstitution of anatomic fiber architecture and uses constitutive modeling to evaluate construct function. A modified electrospinning technique was utilized to generate aligned nanofibrous polymer scaffolds for engineering the basic functional unit of the AF, a single lamella. Scaffolds were tested in uniaxial tension at multiple fiber orientations, demonstrating a nonlinear dependence of modulus on fiber angle that mimicked the nonlinearity and anisotropy of native AF. A homogenization model previously applied to native AF successfully described scaffold mechanical response, and parametric studies demonstrated that nonfibrillar matrix, along with fiber connectivity, are key contributors to tensile mechanics for engineered AF. We demonstrated that AF cells orient themselves along the aligned scaffolds and deposit matrix that contributes to construct mechanics under loading conditions relevant to the in vivo environment. The homogenization model was applied to cell-seeded constructs and provided quantitative measures for the evolution of matrix and interfibrillar interactions. Finally, the model demonstrated that at fiber angles of the AF (28 degrees-44 degrees), engineered material behaved much like native tissue, suggesting that engineered constructs replicate the physiologic behavior of the single AF lamella. Constitutive modeling provides a powerful tool for analysis of engineered AF neo-tissue and native AF tissue alike, highlighting key mechanical design criteria for functional AF tissue engineering. (C) 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.