Graduate Institute of Biochemical and Biomedical Engineering, Chang Gung University, Taoyuan, Taiwan.
Biomed Microdevices. 2011 Aug;13(4):789-98. doi: 10.1007/s10544-011-9549-z.
Mammalian cells are sensitive to extracellular microenvironments. In order to precisely explore the physiological responses of cells to tensile loading, a stable and well-defined culture condition is required. In this study, a high-throughput perfusion-based microbioreactor platform capable of providing dynamic equibiaxial tensile loading to the cultured cells under a steady culture condition was proposed. The mechanism of generating tensile stimulation to cells is based on the pneumatically-driven deformation of an elastic polydimethylsiloxan (PDMS) membrane which exerts tensile loading to the attached cells. By modulating the magnitude and frequency of the applied pneumatic pressure, various tensile loading can be generated in a controllable manner. In this study, the microbioreactor platform was designed with the aid of the experimentally-validated finite element (FE) analysis to ensure the loading of tensile strain to cells is uniform and definable. Based on this design, the quantitative relationship between the applied pneumatic pressure and the generated tensile strain on the PDMS membrane was established via FE analysis. Results demonstrated that the proposed device was able to generate the tensile strain range (0~0.12), which covers the physiological condition that articular chondrocytes experience tensile strain under human walking condition. In this study, moreover, the effect of tensile loading on the metabolic, biosynthetic and proliferation activities of articular chondrocytes was investigated. Results disclosed that the dynamic tensile loading of 0.12 strain at 1 Hz might significantly up-regulate the synthesis of glycosaminoglycans while such stimulation was found no significant influence on the metabolic activity, the synthesis of collagen, and the proliferation of chondrocytes. Overall, this study has presented a high throughput perfusion micro cell culture device that is suitable for precisely exploring the effect of tensile loading on cell physiology.
哺乳动物细胞对外界微环境敏感。为了精确地研究细胞对拉伸载荷的生理响应，需要一个稳定且明确的培养条件。在这项研究中，提出了一种高通量基于灌注的微生物反应器平台，该平台能够在稳定的培养条件下向培养的细胞提供动态的双轴拉伸载荷。产生细胞拉伸刺激的机制基于气动驱动弹性聚二甲基硅氧烷（PDMS）膜的变形，该膜向附着的细胞施加拉伸载荷。通过调节施加气压的幅度和频率，可以以可控的方式产生各种拉伸载荷。在这项研究中，借助经过实验验证的有限元（FE）分析来设计微生物反应器平台，以确保向细胞施加的拉伸应变均匀且可定义。基于此设计，通过 FE 分析建立了施加气压与 PDMS 膜产生的拉伸应变成之间的定量关系。结果表明，该设备能够产生（0~0.12）的拉伸应变范围，涵盖了关节软骨细胞在人类行走条件下经历拉伸应变的生理条件。此外，本研究还研究了拉伸载荷对关节软骨细胞代谢、生物合成和增殖活性的影响。结果表明，0.12 应变、1Hz 的动态拉伸载荷可能会显著上调糖胺聚糖的合成，而这种刺激对代谢活性、胶原合成和软骨细胞增殖没有显著影响。总体而言，本研究提出了一种高通量灌注微细胞培养装置，适用于精确研究拉伸载荷对细胞生理学的影响。
