Development of the hepatic toxicity evaluation test using a mini-bioartificial liver and ^<13>C stability isotope compounds

人类细胞的新生物评价方法是填补人类与实验动物之间代谢差异的一种技术。然而，传统的单层培养方法无法再现细胞在体内的功能。利用三维高密度培养方法制备的生物人工器官可以作为人体组织器官的替代器官。在本研究中，我们使用^<13>C稳定性同位素化合物在替代器官中进行代谢和毒性试验的开发，以进行敏感的代谢评估。与单层培养相比，生物反应器中的三维培养是一种大规模的培养。因此，操作大量的反应堆是困难的。因此，有必要建立一个系统来仔细判断一个反应堆的运行情况。为了维持简单的三维培养系统，我们首先制作了一个混合气供氧器，没有CO_2培养箱和大型控制器，供氧系统。开发了代谢排放^<13>C稳定同位素标记化合物的CO_2测定方法，对培养过程进行毒性评价和一定的特异性代谢评价。这种方法的优点是；1)我们可以通过使用特定的标记化合物来评估特定的代谢；2)我们可以很容易地从水库中获得作为废气的样品，而不需要打开反应器；3)我们可以很容易地用红外分光光度计测量^<13>CO_2，仅需2'30"。作为这项研究的结果，我们开发了代谢和毒性评估系统，用于使用生物人工器官和^<13>C稳定同位素标记化合物在体内进行代谢模拟。客观评价将采用代谢模型和计算机模拟。在动物和临床试验之前，利用生物人工器官和稳定同位素标记的化合物进行替代分析，将在未来评价药物和食品的毒性/代谢质量方面发挥重要作用。少

The xinobiotic evaluation method used by human cells is a technique to fill metabolic differences between Homo sapiens and experimental animals. However, conventional single-layered culture method cannot reproduce the functions of cell in the body. We can use the bioartificial organs which we made by three-dimensional high density culture method as a substitute organ of human tissue and organs. In the present study, we performed development of the metabolic and toxic test using ^<13>C stability isotope compounds for sensitive metabolic evaluation in a substitute organ.Three-dimensional culture in a bioreactor is a large-scaled culture compared to single-layered culture. Therefore it is difficult to operate a lot of reactors. On this account a system to carefully judge the operation situation of one reactor is necessary. At first we made a mixed gas feeder to maintain simply three-dimensional culture system, without a CO_2 incubator and a large-scaled controller, supplied oxygen of cult … More ure system. I also developed the metabolism discharge ^<13>CO_2 assay method using a ^<13>C stability isotope labeled compound to perform toxic evaluation and a certain specific metabolism evaluation on culture course. The advantages of this method are ; 1)We can evaluate a specific metabolism by using a specific labeled compound, 2)We can easily get samples as exhaust gas from a reservoir, and do not need to open a reactor, and 3) We can easily measure ^<13>CO_2 for only 2'30" by a infrared spectrophotometer.As a result of this study, we developed the metabolic and toxic evaluation system for performing metabolic simulation in the body using bioartificial organs and ^<13>C stability isotope labeled compounds. Objective evaluation will apply metabolism modeling and computer simulation. Before animal and clinical examinations, the substitute analysis using bioartificial organs and a stability isotope labeled compounds will become useful for evaluation of the toxicity/metabolism of quality of drugs and foods in future. Less