Katakai D, Imura M, Ando W, Tateishi K, Yoshikawa H, Nakamura N, Fujie H
Biomechanics Laboratory, Department of Mechanical Engineering, Kogakuin University, 2665-1 Nakanomachi, Hachioji, Tokyo 192-0015, Japan.
Clin Biomech (Bristol). 2009 Jan;24(1):110-6. doi: 10.1016/j.clinbiomech.2008.07.003. Epub 2008 Nov 6.
It is crucial to develop an effective methodology for restoring adequate compressive properties to osteoarthritic cartilage. We have developed a scaffold-free tissue engineered construct cultured from synovium-derived mesenchymal stem cells. However, the compressive properties of cartilage-like tissues repaired with the construct have not been fully determined.
Synovium-derived mesenchymal stem cells were cultured in Dulbecco's modified Eagle's medium to produce the tissue engineered construct. Implantation of the construct into cylindrically-shaped partial defects in femoral cartilage in an experimental porcine model was performed. Six months after implantation, cartilage-like tissues repaired with the construct were subjected to static and cyclic compression tests using a micro-unconfined compression test apparatus developed in our laboratory.
The developed apparatus was validated in preliminary examinations. The repaired tissues exhibited rate-dependent viscoelastic properties; the compressive modulus was slightly lower than that of normal cartilage at a rate of 4 microm/s, while no difference was observed at a rate of 100 microm/s. In contrast, the repaired tissue without the construct exhibited rate-independent, non-viscoelastic properties. In the cyclic compression test, however, the compressive strain was significantly larger in both repaired tissues as compared with normal cartilage.
Although the quasi-static compressive properties of the repaired tissue with the construct, indicating rate-dependent and viscoelastic behaviors, are comparable to normal cartilage, the cyclic compressive strain increases more rapidly than in normal cartilage. It is suggested that the differences between the tissues and normal cartilage are attributable to the increased permeability of the extracellular matrix.
开发一种有效的方法来恢复骨关节炎软骨的足够压缩特性至关重要。我们已经开发了一种由滑膜来源的间充质干细胞培养的无支架组织工程构建体。然而，用该构建体修复的软骨样组织的压缩特性尚未完全确定。
将滑膜来源的间充质干细胞在杜尔贝科改良的 Eagle 培养基中培养以产生组织工程构建体。将该构建体植入实验猪模型的股骨软骨圆柱形部分缺损中。植入六个月后，使用我们实验室开发的微无侧限压缩试验装置对用该构建体修复的软骨样组织进行静态和循环压缩试验。
开发的装置在初步检查中得到验证。修复后的组织表现出速率依赖性粘弹性特性；在 4 微米/秒的速率下，压缩模量略低于正常软骨，而在 100 微米/秒的速率下未观察到差异。相比之下，未使用构建体的修复组织表现出与速率无关的非粘弹性特性。然而，在循环压缩试验中，与正常软骨相比，两种修复组织中的压缩应变均明显更大。
尽管用该构建体修复的组织的准静态压缩特性表明其具有速率依赖性和粘弹性行为，与正常软骨相当，但循环压缩应变比正常软骨增加得更快。提示组织与正常软骨之间的差异归因于细胞外基质通透性的增加。
