Conventional biomedical studies are carried out either in vivo or in vitro. In vivo research utilizing intact organisms can provide high resemblance to the real physiological conditions. However, the variations in experimental results are relatively high due to the high complication of organisms and the great diversity of entities. It is also difficult to observe the biological processes in whole organisms. On the other hand, in vitro research utilizing isolated cells can provide a purified environment and amplify the observed reactions in experiments. But it is unable to reflect the complex physiological responses found in vivo.
In this work, a liver labchip integrating a dielectrophoretic (DEP) cell patterning technique and a microfluidic system is developed for constructing an in vitro engineered liver tissue mimicking the base unit, hepatic lobule, of liver. The liver labchip is proposed not only to treat as a disease model to study hepatitis B, hepatitis C and liver cancer, but also to serve a platform for drug screening. DEP forces are utilized as the cell-patterning mechanism to manipulate heterogeneous cells for mimicking the inherent hepatic morphology and increasing the cell-cell interaction. The microfluidic system is designed for not only long-term culture of the engineered liver tissues in triplicate condition but also well control of the culture environment in vitro to mimic a real condition in vivo. The three important features of the proposed liver labchip are: (1) The designs of the microfluidic system which provide consistent flow velocity, consistent cell density, and uniform cell distribution. (2) About five hundred thousand and three hundred thousand of hepatocytes and fibroblasts are alternately organized into an array of multiple radial patterns to from a 92 mm2 precise lobule-mimetic engineered liver tissue by flourishing the DEP ability. (3) The experimental results reveal that the liver-specific functions such as, albumin secretion and P450-1A1 enzyme activity of DEP-engineered liver tissue show 32.49% and 68.41% of enhancement when compared with non-patterned liver cells, respectively.
This research results are quite remarkable and foresighted and we are the first in the world to demonstrate the large-area parallel manipulation of several hundred thousands of cells for constructing an engineered liver tissue. By the proposed liver labchip, the engineered liver tissue can serve as an excellent model for the investigation of liver physiology and pathophysiology. Meanwhile, this liver labchip is able to extract the bioinformation from the engineered tissues in response to various drugs, which will be useful for biomedical applications such as drug screening. Finally, the present gap between in vivo and in vitro studies can be bridged via this liver labchip.

系統晶片，以仿肝臟基本單元肝小葉為目標來體外重建肝組織，藉以當作B肝、C肝、癌症病理及藥物篩選的平台。晶片中利用介電泳力當作細胞排列的機制，以操控不同種類的細胞，建構仿真實肝組織的型態，以促進細胞與細胞的相互作用。另外，設計微流體系統，得以進行生醫檢測採用的三重覆實驗，並長期培養重建的肝組織與控制體外培養環境以近似真實體內環境。所提出的肝臟實驗室晶片展現了三個重要的特色：(1)設計的微流體系統能夠提供一致的流速、一致的細胞密度與均勻的細胞分佈；(2)藉由介電泳的能力，大約五十萬個肝細胞與三十萬個纖維母細胞能夠先後的排列成多重放射狀圖案陣列並形成約九十六豪米面積之仿肝小葉肝組織；(3)實驗結果顯示，對於介電泳排列的工程肝組織其特有的白蛋白分泌與P450-1A1酵素活性表現，各別有32.49% 與 68.41%的顯著提升。
本研究結果相當具前瞻與獨特性，展現世界上第一個有能力大面積平行的操控幾十萬顆細胞，並將異種細胞仿肝小葉結構排列，以體外重建工程的肝組織。藉由所提出的肝臟晶片，其工程肝臟組織可以當成研究肝臟的生理學與病理生理學模型。同時肝臟晶片亦能夠利用工程肝臟組織在不同的藥物情況下反映不同的結果，而有效的應用在藥物篩選。且現今體外與體內的研究亦能夠利用所提出的肝臟晶片而有所聯接。

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