| 摘要: |
| 目的 明确小鼠肝脏中的细胞角蛋白19（cytokeratin 19，CK19）阳性（CK19+）细胞是否可分化为成熟肝细胞。方法 利用CK19CreERT小鼠和Rosa26-GFP小鼠杂交得到CK19CreERT/Rosa26-GFP双转基因小鼠，注射他莫昔芬（tamoxifen，TM）后检测小鼠肝脏中CK19+细胞的GFP标记情况。在此基础上分别构建3，5-二乙氧基羰基-1，4-二氢-2，4，6-三甲基吡啶和四氯化碳（carbon tetrachloride，CCl4）肝脏损伤模型，采用肝脏组织冰冻切片结合免疫荧光染色检测肝脏中GFP标记的CK19+细胞的分化情况。结果 获得CK19CreERT/Rosa26-GFP双转基因小鼠，免疫荧光染色结果显示CK19+细胞可被GFP标记。在DDC肝脏损伤模型小鼠中检测到增生性小胆管内有GFP+细胞，这些GFP+细胞表达胆管上皮细胞标志物CK19，且DDC肝损伤模型小鼠中GFP+胆管细胞比例高于未损伤对照组[（63.5±6.3）% vs （53.6±4.8）%，P<0.05]；在CCl4肝损伤模型组小鼠中检测到肝脏实质细胞中有GFP+细胞，这些GFP+细胞表达成熟肝细胞标志物白蛋白（ALB），且CCl4肝损伤模型组小鼠肝脏中GFP+细胞比例高于未损伤对照组[（0.15±0.02）% vs （0.008±0.003）%，P<0.01]。结论 小鼠肝脏内的CK19+细胞群体中存在具有肝向分化潜能的前体细胞，可能为真正的肝干细胞的识别鉴定提供一个新线索。 |
| 关键词: 肝干细胞 CK19 转基因小鼠 CK19CreERT Rosa26-GFP |
| DOI：10.16781/j.0258-879x.2017.05.0536 |
| 投稿时间：2017-03-24修订日期：2017-04-17 |
| 基金项目:国家自然科学基金（31401166，81670573），国家重点基础研究发展计划（“973计划”，2010CB945602）. |
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| Hepatic differentiation feature of cytokeratin 19 positive cells in mouse liver |
| LU Lian1,CHEN Fei1,YU Bing1,ZHAO Jian2,HU Yi-ping1* |
(1. Department of Cell Biology, College of Basic Medical Sciences, Second Military Medical University, Shanghai 200433, China;
2. International Joint Cancer Institute, Second Military Medical University, Shanghai 200433, China
*Corresponding author) |
| Abstract: |
| Objective To determine whether the cytokeratin 19 (CK19) positive (CK19+) cells in mouse liver have the potential of differentiation into mature hepatocytes. Methods The CK19CreERT/Rosa26-GFP double-transgenic mice were obtained by hybridizing CK19CreERT mouse with Rosa26-GFP mouse and the GFP-labeled CK19+ cells were observed in mouse liver after tamoxifen (TM) injection. Then we constructed the 3, 5-diethoxycarbonyl-1, 4-dihydrocollidine (DDC)-induced liver injury mouse model and carbon tetrachloride (CCl4)-induced liver injury mouse model in CK19CreERT/Rosa26-GFP double-transgenic mouse and determined the differentiation potential of GFP-labeled CK19+ cells by frozen sections and immunofluorescence staining of liver tissues. Results The CK19CreERT/Rosa26-GFP double-transgenic mice were obtained and the CK19+ cells were genetically labeled with GFP after TM injection. In DDC model, we detected GFP+ cholangiocytes in proliferating ductules, in which CK19, a marker for biliary epithelial cells was expressed, and the proportion of GFP+ cholangiocytes in the DDC model group ([63.5±6.3]%) was significantly higher than that in the control group ([53.6±4.8]%, P<0.05). In CCl4 model, we identified GFP+ hepatocytes in the liver parenchyma; we also found that the hepatocyte-specific marker albumin was expressed in the GFP+ hepatocytes; and the proportion of GFP+ hepatocytes in the CCl4 model group ([0.15±0.02]%) was significantly higher than that in control group ([0.008±0.003]%, P<0.01). Conclusion There are liver stem cells with a potential for hepatic differentiation in the CK19+ cells in mouse liver, which may provide a new clue for the identification of liver stem cells. |
| Key words: liver stem cells CK19 transgenic mouse CK19CreERT Rosa26-GFP |
