Tania Marshella, Hsu Myat Noe, Png Si Ning, Leo Hwa Liang, Toh Guoyang William, Birgersson Erik
Dept. of Biomedical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117575, Singapore.
Biotechnol Prog. 2014 Mar-Apr;30(2):418-28. doi: 10.1002/btpr.1867. Epub 2014 Jan 21.
Conventional two-dimensional cultures in monolayer and sandwich configuration have been used as a model for in vitro drug testing. However, these culture configurations do not present the actual in vivo liver cytoarchitecture for the hepatocytes cultures and thus they may compromise the cells liver-specific functions and their cuboidal morphology over longer term culture. In this study, we present a three-dimensional polydimethylsiloxane (PDMS) scaffold with interconnected spherical macropores for the culturing of rat liver cells (hepatocytes). The scaffolds were integrated into our perfusion enhanced bioreactor to improve the nutrients and gas supply for cell cultures. The liver-specific functions of the cell culture were assessed by their albumin and urea production, and the changes in the cell morphology were tracked by immunofluorescence staining over 9 days of culture period. N-Acetyl-Para-Amino-Phenol (acetaminophen) was used as drug model to investigate the response of cells to drug in our scaffold-bioreactor system. Our experimental results revealed that the perfusion enhanced PDMS-based scaffold system provides a more conducive microenvironment with better cell-to-cell contacts among the hepatocytes that maintains the culture specific enzymatic functions and their cuboidal morphology during the culturing period. The numerical simulation results further showed improved oxygen distribution within the culturing chamber with the scaffold providing an additional function of shielding the cell cultures from the potentially detrimental fluid induced shear stresses. In conclusion, this study could serve a crucial role as a platform for future preclinical hepatotoxicity testing.
传统的单层和夹心结构二维培养已被用作体外药物测试的模型。然而,这些培养结构并未呈现肝细胞培养的实际体内肝脏细胞结构,因此在长期培养中可能会损害细胞的肝脏特异性功能及其立方形态。在本研究中,我们提出了一种具有相互连接的球形大孔的三维聚二甲基硅氧烷(PDMS)支架,用于培养大鼠肝细胞。将支架整合到我们的灌注增强生物反应器中,以改善细胞培养的营养物质和气体供应。通过细胞培养物中白蛋白和尿素的产生来评估细胞培养的肝脏特异性功能,并在9天的培养期内通过免疫荧光染色追踪细胞形态的变化。使用N-乙酰对氨基酚(对乙酰氨基酚)作为药物模型,研究细胞在我们的支架-生物反应器系统中对药物的反应。我们的实验结果表明,灌注增强的基于PDMS的支架系统提供了一个更有利的微环境,肝细胞之间具有更好的细胞间接触,在培养期间维持了培养物的特定酶功能及其立方形态。数值模拟结果进一步表明,支架改善了培养室内的氧气分布,提供了额外的功能,可保护细胞培养物免受潜在有害的流体诱导剪切应力的影响。总之,本研究可作为未来临床前肝毒性测试的关键平台发挥重要作用。