上皮型钙黏蛋白对小鼠胚胎干细胞向肝细胞分化的增强调控作用  

Roles of E-cadherin in enhancing the in vitro differentiation of hepatocytes from murine embryonic stem cells

作　　者：胡安斌[1] 商昌珍[2] 闵军[2] 蔡继业[3] 何晓顺[1] 

机构地区：[1]中山大学附属第一医院器官移植科,广州510080 [2]中山大学附属孙逸仙纪念医院肝胆外科 [3]暨南大学生命科学院

出　　处：《中华医学杂志》2012年第44期3143-3146,共4页National Medical Journal of China

基　　金：国家自然科学基金（81172831、30700398）;国家“863”计划专题课题（2007AA02Z117）;广东省科技攻关计划（20098030801126）;广东省自然科学基金（10151008901000200）;中央高校基本科研业务费专项资金.中山大学青年教师培育项目（09ykpy28）

摘　　要：目的观察上皮型钙黏蛋白（E-cad）对小鼠胚胎干细胞（ESC）在体外向肝细胞分化的增强调控作用。方法将E-cad转染入BALB／c小鼠ESC使其稳定表达，再利用肝细胞生长因子（HGF）等诱导其向肝细胞分化。然后用逆转录一聚合酶链反应（RT-PCR）检测肝细胞标记基因ALB、TAT、Cyp7a1的表达，用RIA法检测培养液ALB和尿素合成情况，显微镜观察分化细胞数量和黏附状态。结果（1）普通ESC在拟胚体（EB）形成后表达E-cad最强，其后表达降低至17d不再表达，而E-cad-ESC则稳定表达E-cad；（2）肝细胞标记基因ALB、TAT和Cyp7a1在E-cad—ESC组表达要早于或强于普通ESC组，ALB和尿素合成方面，E-cad-ESC组早于普通ESC组[普通ESC组，ALB最早出现于第11天，浓度为（0．20±0．03）mg／L，在17d达到最高为（3．71±0．45）mg／L；尿素最早出现于第12天，浓度为（8．01±1．21）μmol／L，在17d达到最高为（45．01±8．01）μmol／L。E-cad—ESC组，ALB最早出现于第9天，浓度为（0．19±0．03）mg／L，在17d达到最高为（5．52±0．82）mg／L；尿素最早出现于第10天，浓度为（5．90±1．21）μmol／L，在17d达到最高为（56．93±9．03）μmol／L]，差异有统计学意义；（3）普通ESC在分化后期表现为松散的细胞群落，分化细胞数量稀少，E—cad—ESC分化细胞数量明显增多，细胞黏附能力增强并呈紧密的多层生长。结论E—cad可增强ESC向肝细胞的分化作用，表现为分化细胞数量增多并呈多层生长，ALB及尿素合成能力增强，有望成为一种在ESC向肝脏方向分化研究中的重要调控因子。Objective To investigate the roles of E-cadherin （E-cad） in enhancing the in vitro differentiation of hepatocytes from murine embryonic stem cells （ESCs）. Methods Exogenous E-cad was transfected into BALB/c routine ESCs to enable its stable expression. Then hepatic differentiation from E- cad-ESCs was induced by such growth factors as hepatocyte growth factor （HGF）, fibroblast growth factor （FGF） and transforming growth factor （TGF）. And the expressions of hepatic markers ALB, TAT, Cyp7a1 and urea were detected. The morphology of hepatic differentiation was observed under microscopy. Results E-cad expression gradually decreased in normal ESC differentiation, but was stably expressed in E-ead- ESCs. In E-ead-ESC group, hepatic markers ALB, TAT and CYP7a1 were expressed earlier or higher than that in normal ESC group, and the concentrations of ALB and urea were significantly higher than that in normal ESC group. The adhesion of the differentiated E-ead-ESCs was significantly enhanced compared with the normal ESCs. They maintained close connections and multidimensional growth. Cell number of hepatocytes from ESC increased significantly in E-cad-ESC group. Conclusion E-cad enhances the hepatic differentiation of ESC by increasing the number of differentiated cells and increasing the synthetic capacity of ALB and urea.

关 键 词：胚胎干细胞 上皮型钙黏蛋白 细胞分化 肝细胞 

分 类 号：R329[医药卫生—人体解剖和组织胚胎学]