Potentiality of endothelial to mesenchymal transition in ex-vivo rarely contribute to hepatic fibrogenesis in vivo

离体内皮向间质转化的潜力很少有助于体内肝纤维化

基本信息

批准号：
22591507
负责人：
TOMIKAWA Morimasa
金额：
$ 2.83万
依托单位：
Kyushu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2010
资助国家：
日本
起止时间：
2010 至 2012
项目状态：
已结题

项目摘要

BACKGROUND AND AIMS: Recent studies have reported the possibilities of endothelial to messenchymal transition (EndMT) in several tissues, which means endothelial cells migrating into fibrotic tissue exhibit a myofibroblast-like phenotype and may participate in the progression of tissue fibrosis. However, their contribution to fibrosis in liver has not been fully verified yet. We revisited this issue by using liver fibrosis models introduced into transgenic collagen reporter mice. METHODS: Bone marrow of Tie2-Cre, CAG-CAT, GFP double transgenic mice was replaced by cells obtained from wild-type mice harboring endothelial cell-specific Tie2 gene linked to enhanced green fluorescent protein (EGFP) gene. Liver fibrosis was introduce d into those mice by repeated carbon tetrachloride injections. EGFP expression was assessed by confocal microscopic examination.RESULTS: Endothelial cells performed mesenchymal transition during primary culture on plastic. In Tie2-Cre, CAG-CAT, GFP double transgenic mice, endothelial cells express EGFP, at the same time, a large number of EGFP-positive immunocompetent cells were observed. In contrast, Tie2-Cre, CAG-CAT, GFP double transgenic mice whose bone marrow was replaced by cells obtained from wild-type mice have no EGFP positive cells but endothelial cell. Though, double transgenic mice observed many EGFP-positive cells at liver fibrotic area, there were few EGFP-positive cell in double transgenic mice whose bone marrow was replaced by wild-type mice. CONCLUSIONS: By using a specific and sensitive experimental system, which detects cells whose roots were endothelial cells excrusively, we conclude an unexpectedly limited role of EndMT during CCl4induced liver fibrogenesis.

背景和目的：最近的研究报道了多种组织中内皮细胞向间质细胞转化（EndMT）的可能性，这意味着迁移到纤维化组织中的内皮细胞表现出肌成纤维细胞样表型，并可能参与组织纤维化的进展。然而，它们对肝脏纤维化的贡献尚未得到充分证实。我们通过使用引入转基因胶原蛋白报告小鼠的肝纤维化模型重新审视了这个问题。方法：Tie2-Cre、CAG-CAT、GFP 双转基因小鼠的骨髓被取自携带内皮细胞特异性 Tie2 基因（与增强型绿色荧光蛋白 (EGFP) 基因连接）的野生型小鼠的细胞替代。通过重复注射四氯化碳将肝纤维化引入这些小鼠中。通过共聚焦显微镜检查评估EGFP表达。结果：内皮细胞在塑料上原代培养期间进行间质转化。在Tie2-Cre、CAG-CAT、GFP双转基因小鼠中，内皮细胞表达EGFP，同时观察到大量EGFP阳性免疫活性细胞。相反，Tie2-Cre、CAG-CAT、GFP双转基因小鼠的骨髓被野生型小鼠细胞替代，没有EGFP阳性细胞，只有内皮细胞。虽然双转基因小鼠在肝纤维化区域观察到大量EGFP阳性细胞，但在骨髓被野生型小鼠替代的双转基因小鼠中，EGFP阳性细胞很少。结论：通过使用特异且灵敏的实验系统，仅检测根部为内皮细胞的细胞，我们得出结论，EndMT 在 CCl4 诱导的肝纤维形成过程中的作用出人意料地有限。