Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University, Osaka 565-0871, Japan.
Biomaterials. 2012 Jun;33(18):4526-34. doi: 10.1016/j.biomaterials.2012.03.011. Epub 2012 Mar 23.
Hepatocyte-like cells differentiated from human embryonic stem cells (hESCs) or human induced pluripotent stem cells (hiPSCs) are known to be a useful cell source for drug screening. We recently developed an efficient hepatic differentiation method from hESCs and hiPSCs by sequential transduction of FOXA2 and HNF1α. It is known that the combination of three-dimensional (3D) culture and co-culture, namely 3D co-culture, can maintain the functions of primary hepatocytes. However, hepatic maturation of hESC- or hiPSC-derived hepatocyte-like cells (hEHs or hiPHs, respectively) by 3D co-culture systems has not been examined. Therefore, we utilized a cell sheet engineering technology to promote hepatic maturation. The gene expression levels of hepatocyte-related markers (such as cytochrome P450 enzymes and conjugating enzymes) and the amount of albumin secretion in the hEHs or hiPHs, which were 3D co-cultured with the Swiss 3T3 cell sheet, were significantly up-regulated in comparison with those in the hEHs or hiPHs cultured in a monolayer. Furthermore, we found that type I collagen synthesized in Swiss 3T3 cells plays an important role in hepatic maturation. The hEHs or hiPHs that were 3D co-cultured with the Swiss 3T3 cell sheet would be powerful tools for medical applications, such as drug screening.
人胚胎干细胞（hESCs）或人诱导多能干细胞（hiPSCs）分化而来的肝细胞样细胞已被证实是一种用于药物筛选的有用细胞来源。我们最近通过连续转导 FOXA2 和 HNF1α 从 hESCs 和 hiPSCs 中开发了一种高效的肝分化方法。已知三维（3D）培养和共培养的组合，即 3D 共培养，可以维持原代肝细胞的功能。然而，3D 共培养系统对 hESC 或 hiPSC 来源的肝细胞样细胞（分别为 hEH 或 hiPH）的肝成熟作用尚未得到检验。因此，我们利用细胞片工程技术来促进肝成熟。与单层培养的 hEH 或 hiPH 相比，与瑞士 3T3 细胞片共培养的 hEH 或 hiPH 的肝细胞相关标志物（如细胞色素 P450 酶和结合酶）的基因表达水平和白蛋白分泌量显著上调。此外，我们发现瑞士 3T3 细胞中合成的 I 型胶原在肝成熟中起着重要作用。与瑞士 3T3 细胞片共培养的 hEH 或 hiPH 将成为药物筛选等医学应用的有力工具。
