Alterations in the Young's modulus and volumetric properties of chondrocytes isolated from normal and osteoarthritic human cartilage
Alterations in the Young's modulus and volumetric properties of chondrocytes isolated from normal and osteoarthritic human cartilage
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DOI：
10.1016/s0021-9290(98)00166-3
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发表时间：
1999-02-01
影响因子：
2.4
通讯作者：
Guilak, F
中科院分区：
文献类型：
--
作者：
Jones, WR;Ting-Beall, HP;Guilak, F
软骨细胞的力学环境是影响关节软骨细胞外基质维持的重要因素。先前的研究利用关节软骨内软骨细胞的理论模型来预测细胞周围的应力应变和流体流动环境，但目前对实施这些模型所需的细胞特性知之甚少。本研究的目的是表征原代人类软骨细胞的机械行为，并确定非骨关节炎（“正常”）和骨关节炎软骨的软骨细胞的杨氏模量。第二个目标是量化孤立软骨细胞体积因机械变形而发生的变化。微量移液器抽吸技术用于测量单个软骨细胞响应规定压力而进入玻璃微量移液器的变形。这项研究的结果表明，人类软骨细胞表现为粘弹性固体。正常的杨氏模量（0.65 +/- 0.63 kPa，n = 44）和骨关节炎软骨细胞（0.67 +/- 0.86 kPa，n = 69，p = 0.93）之间没有发现差异。在将细胞完全吸入移液管后立即和 600 秒观察到细胞体积的显着差异 (p < 0.001)，并且正常 (11 +/- 11%，ir = 40) 和骨关节炎 (20 +/- 11%，n = 41) 软骨细胞之间的体积变化幅度在两个时间点均显着不同 (p < 0.002)。这一发现表明，骨关节炎软骨的软骨细胞可能改变了响应机械变形的体积调节能力。本研究确定的机械和体积特性将用于软骨细胞-基质相互作用的分析和有限元模型，以便更好地预测细胞体内的机械环境。 (C) 1999 Elsevier Science Ltd. 保留所有权利。
The mechanical environment of the chondrocyte is an important factor that influences the maintenance of the articular cartilage extracellular matrix. Previous studies have utilized theoretical models of chondrocytes within articular cartilage to predict the stress-strain and fluid flow environments around the cell, but little is currently known regarding the cellular properties which are required for implementation of these models. The objectives of this study were to characterize the mechanical behavior of primary human chondrocytes and to determine the Young's modulus of chondrocytes from non-osteoarthritic ('normal') and osteoarthritic cartilage. A second goal was to quantify changes in the volume of isolated chondrocytes in response to mechanical deformation. The micropipette aspiration technique was used to measure the deformation of a single chondrocyte into a glass micropipette in response to a prescribed pressure. The results of this study indicate that the human chondrocyte behaves as a viscoelastic solid. No differences were found between the Young's moduli of normal (0.65 +/- 0.63 kPa, n = 44) and osteoarthritic chondrocytes (0.67 +/- 0.86 kPa, n = 69, p = 0.93). A significant difference in cell volume was observed immediately and 600 s after complete aspiration of the cell into the pipette (p < 0.001), and the magnitude of this volume change between normal (11 +/- 11%, ir = 40) and osteoarthritic (20 +/- 11%, n = 41) chondroctyes was significantly different at both time points (p < 0.002). This finding suggests that chondrocytes from osteoarthritic cartilage may have altered volume regulation capabilities in response to mechanical deformation. The mechanical and volumetric properties determined in this study will be of use in analytical and finite element models of chondrocyte-matrix interactions in order to better predict the mechanical environment of the cell in vivo. (C) 1999 Elsevier Science Ltd. All rights reserved.