Nahmias Yaakov, Casali Monica, Barbe Laurent, Berthiaume Francois, Yarmush Martin L
Center for Engineering in Medicine/Department of Surgery, Massachusetts General Hospital, Shriners Burns Hospital, Harvard Medical School, Boston, MA 02114, USA.
Hepatology. 2006 Feb;43(2):257-65. doi: 10.1002/hep.21016.
Low-density lipoprotein (LDL) is an important carrier of plasma cholesterol and triglycerides whose concentration is regulated by the liver parenchymal cells. Abnormal LDL regulation is thought to cause atherosclerosis, while viral binding to LDL has been suggested to facilitate hepatitis C infection. Primary hepatocytes quickly lose the ability to clear LDL during in vitro culture. Here we show that the coculture of hepatocytes with liver sinusoidal endothelial cells (LSEC) significantly increases the ability of hepatocytes to uptake LDL in vitro. LDL uptake does not increase when hepatocytes are cocultured with other cell types such as fibroblasts or umbilical vein endothelial cells. We find that LSECs induce the hepatic expression of the LDL receptor and the epidermal growth factor receptor. In addition, while hepatocytes in single culture did not take up hepatitis C virus (HCV)-like particles, the hepatocytes cocultured with LSECs showed a high level of HCV-like particle uptake. We suggest that coculture with LSECs induces the emergence of a sinusoidal surface in primary hepatocytes conducive to the uptake of HCV-like particles. In conclusion, our findings describe a novel model of polarized hepatocytes in vitro that can be used for the study of LDL metabolism and hepatitis C infection.
低密度脂蛋白（LDL）是血浆胆固醇和甘油三酯的重要载体，其浓度由肝实质细胞调节。LDL调节异常被认为会导致动脉粥样硬化，而病毒与LDL的结合被认为有助于丙型肝炎感染。原代肝细胞在体外培养过程中会迅速丧失清除LDL的能力。在此我们表明，肝细胞与肝窦内皮细胞（LSEC）共培养可显著提高肝细胞在体外摄取LDL的能力。当肝细胞与其他细胞类型（如成纤维细胞或脐静脉内皮细胞）共培养时，LDL摄取量不会增加。我们发现LSEC可诱导肝组织中LDL受体和表皮生长因子受体的表达。此外，虽然单独培养的肝细胞不摄取丙型肝炎病毒（HCV）样颗粒，但与LSEC共培养的肝细胞显示出高水平的HCV样颗粒摄取。我们认为，与LSEC共培养可诱导原代肝细胞出现有利于摄取HCV样颗粒的窦状表面。总之，我们的研究结果描述了一种体外极化肝细胞的新模型，可用于研究LDL代谢和丙型肝炎感染。
