Transdifferentiation of mature rat hepatocytes into bile duct-like cells in vitro
Transdifferentiation of mature rat hepatocytes into bile duct-like cells in vitro
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DOI：
10.1016/s0002-9440(10)62328-0
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发表时间：
2005-04-01
影响因子：
6
通讯作者：
Enomoto, K
中科院分区：
文献类型：
--
作者：
Nishikawa, Y;Doi, Y;Enomoto, K
我们研究了肝细胞在三维类器官培养系统中的表型可塑性机制，在该系统中，肝细胞球状体被嵌入胶原凝胶基质中。肝细胞;在培养后不久表达了几种胆管标记物，包括细胞角蛋白（CK）19，并在胰岛素和表皮生长因子的存在下在基质内经历了分支形态发生。培养的肝细胞不表达Delta样蛋白，这是卵圆细胞和成肝细胞的特异性标志物。此外，从c-kit突变大鼠（Ws/Ws），这是有缺陷的卵圆细胞的增殖分离的肝细胞，表现出基本上相同的表型变化，从对照组大鼠分离的。肝细胞的胆管样分化与Jagged 1、Jagged 2、Notch 1和几个Notch靶基因的表达增加相关。CK 19表达和分支形态发生受到地塞米松、促分裂原活化蛋白激酶激酶1（MEK 1）抑制剂（PD 98059）和磷脂酰肌醇3-激酶抑制剂（LY 294002）的抑制。在凝胶内培养超过3周后，肝细胞转化为被基底膜包围的管状结构。我们的研究结果表明，肝细胞可能有潜力转分化成胆管样细胞，而不获得干细胞样表型，这是通过特定的蛋白酪氨酸磷酸化途径介导的。
We investigated the mechanism of phenotypic plasticity of hepatocytes in a three-dimensional organoid culture system, in which hepatocytic spheroids were embedded within a collagen gel matrix. Hepatocytes; expressed several bile duct markers including cytokeratin (CK) 19 soon after culture and underwent branching morphogenesis within the matrix in the presence of insulin and epidermal growth factor. Cultured hepatocytes did not express Delta-like, a specific marker for oval cells and hepatoblasts. Furthermore, hepatocytes isolated from c-kit mutant rats (Ws/Ws), which are defective in proliferation of oval cells, showed essentially the same phenotypic changes as those isolated from control rats. The bile duct-like differentiation of hepatocytes was associated with increased expression of Jagged1, Jagged2, Notch1, and several Notch target genes. CK19 expression and branching morphogenesis were inhibited by dexamethasone, a mitogen-activated protein kinase kinase 1 (MEK1) inhibitor (PD98059), and a phosphatidyl inositol 3-kinase inhibitor (LY294002). After being cultured for more than 3 weeks within the gels, hepatocytes transformed into ductular structures surrounded by basement membranes. Our results suggest that hepatocytes might have the potential to transdifferentiate into bile duct-like cells without acquiring a stem-like phenotype and that this is mediated through specific protein tyrosine phosphorylationpathways.