Ijima Hiroyuki, Matsuo Takeshi, Kawakami Koei
Department of Chemical Engineering, Faculty of Engineering, Graduate School, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
J Biosci Bioeng. 2008 Mar;105(3):226-31. doi: 10.1263/jbb.105.226.
Heterospheroids consisting of hepatocytes and bone marrow cells (BMCs) are formed by the mixed coculture of these cells and enhance the expression and maintenance of the liver-specific functions of hepatocytes. Not only the soluble factors derived from these cells, but also functional organoid (heterospheroid) formation, are considered to underlie this coculture effect. Therefore, in the present study, we aimed to clarify the mechanism of this co-culture effect. We performed hepatocyte monoculture with conditioned media prepared from hepatocyte cultures, BMC cultures and a coculture of hepatocytes and BMCs. When using any type of conditioned medium, no hepatocyte spheroids formed, and the hepatocytes formed a monolayer. In addition, an effect for these conditioned media was shown in terms of the albumin production and ammonia metabolism activities of the hepatocytes; conditioned medium from BMCs showed the strongest effect. The monocultured hepatocytes in the conditioned medium derived from BMCs showed equivalent albumin production and ammonia metabolism activities to the cocultured spheroids of hepatocytes and BMCs. Therefore, it was determined that the effect of the coculture of hepatocytes and BMCs was caused by soluble factors derived from BMCs.
由肝细胞和骨髓细胞（BMC）组成的异质球体是通过这些细胞的混合共培养形成的，可增强肝细胞肝脏特异性功能的表达和维持。不仅源自这些细胞的可溶性因子，而且功能性类器官（异质球体）的形成，都被认为是这种共培养效应的基础。因此，在本研究中，我们旨在阐明这种共培养效应的机制。我们用从肝细胞培养物、BMC培养物以及肝细胞与BMC的共培养物制备的条件培养基进行肝细胞单培养。当使用任何类型的条件培养基时，均未形成肝细胞球体，肝细胞形成了单层。此外，这些条件培养基在肝细胞的白蛋白产生和氨代谢活性方面显示出作用；来自BMC的条件培养基显示出最强的作用。在源自BMC的条件培养基中进行单培养的肝细胞显示出与肝细胞和BMC的共培养球体相当的白蛋白产生和氨代谢活性。因此，确定肝细胞与BMC共培养的效应是由源自BMC的可溶性因子引起的。
