Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University, Yoshida-Ushinomiya-cho, Sakyo-ku, Kyoto, 606-8501, Japan.
Ecole Normale Supérieure, CNRS-ENS-UPMC UMR 8640, 24 Rue Lhomond, 75005, Paris, France.
Biomed Microdevices. 2019 Jul 15;21(3):73. doi: 10.1007/s10544-019-0423-8.
Liver-on-a-Chip technology holds considerable potential for applications in drug screening and chemical-safety testing. To establish such platforms, functional hepatocytes are required; however, primary hepatocytes are commonly used, despite problems involving donor limitations, lot-to-lot variation, and unsatisfactory two-dimensional culture methods. Although human pluripotent stem cells (hPSCs) may represent a strong alternative contender to address the aforementioned issues, remaining technological challenges include the robust, highly efficient production of high-purity hepatic clusters. In addition, current Liver-on-a-Chip platforms are relatively complicated and not applicable for high-throughput experiments. Here, we develop a very simple Liver-on-a-Chip platform with mature and functional hepatocyte-like cells derived from hPSCs. To establish a method for hepatic differentiation of hPSCs, cells were first treated by inhibiting the phosphoinositide 3-kinase- and Rho-associated protein kinase-signaling pathways to stop self-renewal and improve survival, respectively, which enabled the formation of a well-defined endoderm and facilitated hepatocyte commitment. Next, a simple microfluidic device was used to create a three-dimensional (3D) culture environment that enhanced the maturation and function of hepatocyte-like cells by increasing the expression of both hepatic maturation markers and cytochrome P450. Finally, we confirmed improvements in hepatic functions, such as drug uptake/excretion capabilities, in >90% of 3D-matured hepatocyte-like cells by indocyanin green assay. These results indicated that the incorporation of hPSC-derived hepatocytes on our Liver-on-a-Chip platform may serve to enhance the processes involved in drug screening and chemical-safety testing.
芯片上肝脏技术在药物筛选和化学安全测试的应用中具有相当大的潜力。为了建立这样的平台,需要功能性肝细胞;然而,尽管存在供体限制、批次间差异和二维培养方法不理想等问题,通常还是使用原代肝细胞。虽然人多能干细胞 (hPSCs) 可能是解决上述问题的强有力的替代候选者,但仍存在技术挑战,包括高效、高纯度肝簇的稳健生产。此外,目前的芯片上肝脏平台相对复杂,不适用于高通量实验。在这里,我们开发了一种非常简单的芯片上肝脏平台,该平台使用源自 hPSCs 的成熟且功能齐全的肝样细胞。为了建立 hPSCs 肝分化的方法,首先通过抑制磷脂酰肌醇 3-激酶和 Rho 相关蛋白激酶信号通路来处理细胞,分别停止自我更新和提高存活率,从而形成定义明确的内胚层并促进肝细胞的分化。接下来,使用简单的微流控装置创建三维 (3D) 培养环境,通过增加肝成熟标志物和细胞色素 P450 的表达来增强肝样细胞的成熟和功能。最后,通过吲哚菁绿测定法,我们证实了 3D 成熟肝样细胞中超过 90%的药物摄取/排泄能力等肝功能得到了改善。这些结果表明,在我们的芯片上肝脏平台上整合 hPSC 衍生的肝细胞可能有助于增强药物筛选和化学安全测试过程。