Expression and its significance of telomerase in rat hepatic oval cells
10.3760/cma.j.issn.1673-9752.2009.03.017
- VernacularTitle:端粒酶在大鼠肝卵圆细胞中表达的意义
- Author:
Wei ZHANG
;
Xiaoping CHEN
;
Shuai XIANG
;
Feng ZHANG
;
Hanhua DONG
;
Lei ZHANG
;
Lin CHEN
;
Wanguang ZHANG
- Publication Type:Journal Article
- Keywords:
Oval cell;
Telomerase;
Cell separation;
Identification
- From:
Chinese Journal of Digestive Surgery
2009;8(3):204-208
- CountryChina
- Language:Chinese
-
Abstract:
Objcctive To detect the telomerase activity in rat hepatic oval cells, and to explore the relationship between telomerase expression and the proliferation and differentiation of oval cells. Methods The 2-acetamidofluorene/partial bepatectomy (2-AAF/PH) rat model was used to induce the proliferation of oval cells. Oval cells were isolated by modified collagenase perfusion and gradient centrifugation. Electron microscope exami-nation and immunofluorescence were adopted to identify oval cells. Immunohistochemistry, RT-PCR and fluores-cence quantitative PCR were used to detect the expression of telomerase in oval cells. All the data collected were analyzed by t test. Results The proliferatiun of oval cells was successfully induced by 2-AAF/PH rat model. Freshly isolated oval cells showed a large and ovoid nuclei, a small proportion of cytomplasm and a cobblestone appearance. When viewed by electron microscopy, there were few and immature organelles, and the nucleus/ cytoplasm ratio was high. Immunofluorescence staining showed that oval cells expressed OV-6, alpha-fetoprotein, cytokeratin-19, albumin and c-kit. Telomerase reverse transcriptase (TERT) was located in the nuclei of oval cells which were around the portal areas. As oval cells differentiated into small hepatocytes, the number of TERT-positive cells decreased significantly. The expression level of TERT mRNA in normal rat liver tissue was 2.27 times higher than that in LE-6 oval cells; the expression level of TERT mRNA in the isolated oval cells was 1.26 times higher than that in LE-6 oval cells. The telomerase activity decreased gradually (from △A=1.05, 1.15 to △A=0.25, 0.45) as the increase of oval cells passage (from passage 24 to passage 40) (t=17.74, 12.38, P<0.05). Conclusions Oval cells have telomerase activity. Telomerase may be indispensable for maintaining the proliferative and multi-directional differentiation abilities of oval cells.
