Modulation of the mechanical properties of tissue engineered cartilage.
Modulation of the mechanical properties of tissue engineered cartilage.
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DOI：
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发表时间：
2000
期刊：
影响因子：
1.1
通讯作者：
Ivan Martin;Bojana Obradovic;S. Treppo;A. Grodzinsky;R. Langer;L. Freed;G. Vunjak‐Novakovic
中科院分区：
文献类型：
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作者：
Ivan Martin;Bojana Obradovic;S. Treppo;A. Grodzinsky;R. Langer;L. Freed;G. Vunjak‐Novakovic
使用软骨细胞、可生物降解聚合物支架和组织培养生物反应器在体外培养软骨结构。在目前的工作中，我们研究了如何通过体外培养的条件和时间来调节工程软骨的组成和力学性能，使用三种不同的环境：静态烧瓶，混合烧瓶和旋转容器。4-6周后，静态培养产生小而脆弱的构建物，而混合烧瓶中的湍流诱导形成外部纤维囊；这两种环境都会导致结构的机械性能较差。在旋转血管的动态层流场中自由悬浮培养的构建体，其糖胺聚糖和胶原蛋白含量最高（分别为天然软骨的75%和39%），力学性能最佳（平衡模量、水力通透性、动态刚度和流动势均约为天然软骨测量值的20%）。软骨结构中的软骨细胞在旋转生物反应器中长时间培养后仍保持代谢活性和表型稳定。糖胺聚糖的湿重分数和7个月构建的平衡模量达到或超过了新鲜外植的天然软骨的相应值。综上所述，这些发现表明，可以通过优化组织培养生物反应器中的流体动力学条件和组织培养的持续时间来设计天然软骨的功能等效物。
Cartilaginous constructs have been grown in vitro using chondrocytes, biodegradable polymer scaffolds, and tissue culture bioreactors. In the present work, we studied how the composition and mechanical properties of engineered cartilage can be modulated by the conditions and duration of in vitro cultivation, using three different environments: static flasks, mixed flasks, and rotating vessels. After 4-6 weeks, static culture yielded small and fragile constructs, while turbulent flow in mixed flasks induced the formation of an outer fibrous capsule; both environments resulted in constructs with poor mechanical properties. The constructs that were cultured freely suspended in a dynamic laminar flow field in rotating vessels had the highest fractions of glycosaminoglycans and collagen (respectively 75% and 39% of levels measured in native cartilage), and the best mechanical properties (equilibrium modulus, hydraulic permeability, dynamic stiffness, and streaming potential were all about 20% of values measured in native cartilage). Chondrocytes in cartilaginous constructs remained metabolically active and phenotypically stable over prolonged cultivation in rotating bioreactors. The wet weight fraction of glycosaminoglycans and equilibrium modulus of 7 month constructs reached or exceeded the corresponding values measured from freshly explanted native cartilage. Taken together, these findings suggest that functional equivalents of native cartilage can be engineered by optimizing the hydrodynamic conditions in tissue culture bioreactors and the duration of tissue cultivation.