生体様の代謝と輸送を再現する肝組織マイクロデバイス

为了实现具有多种生物学功能的基于肝细胞的分析，我们研究了微孔装置和微流控系统的特性，以更好地代谢和未来的胆汁回收。在微孔装置的情况下，我们制作了金字塔形微孔的蜂窝状网络以产生小聚集体。 此外，我们通过Matrigel或肝窦内皮细胞系的覆盖来优化微环境。虽然我们成功地形成了稳定附着的聚集体，但不幸的是，我们不能精确地控制微孔中心胆汁袋的形成。因此，我们决定将微孔改为“虚拟微孔”，即在PDMS表面上形成蛋白质图案。目前正在进行中。作为另一种方法，我们改变了我们以前的设备的设计（Nakao等人，Biomicrofluidics，5，22212，2011）以增加培养基和细胞之间的扩散。为了能够同时监测多个设备，我们设置了8个并行设备以降低流速。成功地实时检查了培养区域的细胞接种。我们尝试了不同的设计和条件，最终能够填充培养区域并获得两行固定的肝细胞。然而，当我们使用新鲜分离的细胞时，我们目前还没有完全成功。实验也在进行中。

To realize hepatocytes-based assays exhibiting many biological functions, we investigated the feasibilities of microwell device and microfluidic system for better metabolism and future bile recovery. In the case of the microwell device, we made a honeycomb network of pyramidal microwells to create small aggregates. In addition, we optimized the microenvironment by the overlay of Matrigel or a liver sinusoidal endothelial cell line. Although we successfully formed stably-attached aggregates, we were unfortunately not able to control precisely the formation of bile pocket in the center of the microwell. We therefore decided to change from microwell to "virtual microwell", namely proteins patterning on PDMS surface. It is on-going at this moment. As an another approach, we changed the design of previous our devices (Nakao et al., Biomicrofluidics, 5, 22212, 2011) to increase the diffusion between the culture medium and cells. To be able to monitor several devices at the time, we made a setup of 8 parallel devices to decrease the flow rate. Cell inoculation to the culture area was successfully checked in real-time. We tried different design and conditions and finally were able to fill the culture area and to get two lines of fixed hepatocytes. However, we have not yet succeeded completely when we use freshly-isolated cells at this moment. The experiments are also on-going now.