温度応答性ポリマー高グラフト化表面によるラット培養肝細胞の長期機能維持（スフェロイド形成） ; Rat Hepatocyte Spheroids Formed on Temperature-Responsive PIPAAm Polymer-Grafted Surface Maintain Long-Term Differentiated Hepatocyte Function

Nagasaki University (長崎大学) ; 博士(医学) ; Background. Although the development of a practicable culture method to maintain long-term hepatocyte function is highly desirable, hepatocytes lose their liver-specific functions rapidly on regular collagen-coated dishes. In this study, we evaluated the efficacy of a special cell culture dish coated with the temperature-responsive polymer poly(N-isopropylacrylamide) (PIPAAm), and observed the morphological and functional changes of hepatocytes on changing the amount of polymer. Methods. Culture plates with varying amounts of PIPAAm polymer (1.5～3.5 times that in the commercially available temperatureresponsive polymer-containing dish (UpCellR, CellSeed, Tokyo, Japan)) were prepared. All dishes were enhanced by adding a layer of rat tail collagen I at a dose of 600 μg/dish for 3 hours. Hepatocytes isolated from Sprague-Dawley rats were cultured in these static culture systems. Morphologic changes and liver-specific functions were evaluated. Results. On day 7 of culture, spheroid formation of hepatocytes was observed in the high-polymer group, with the presence of glycogen and albumin in the spheroid. In the high-polymer group, the rate of albumin production was significantly higher than in the low-polymer group until day 14 of culture (P<0.001). Conclusion. The spheroid formation of hepatocytes cultured in the presence of a high level of PIPAAm showed the long-term maintenance of liver-specific functions in vitro. ; 長崎大学学位論文 学位記番号:博(医歯薬)甲第705号 学位授与年月日:平成26年9月3日 ; Author: Tomonaga Tetsuo, Soyama Akihiko, Yamanouchi Kosho, Takatsuki Mitsuhisa, Kuroki Tamotsu, Koji Takehiko, Eguchi Susumu ; Citation: Acta medica Nagasakiensia, 59(1), pp.1-6; 2014 ; Nagasaki University (長崎大学), 博士(医学) (2014-09-03) ; doctoral thesis