Objective To study a simple and practical method of isolation, culture and identification of hepatic oval cells from adult rat. Methods Wistar adult rats were fed by 2-acetaminofluorere （AAF） and were stimulated by partial hepatectomy to activate the proliferation of hepatic oval cells. After operation 12 days, the livers were resected for isolating oval cells. Hepatic tissue was digested by 0.10% collagenase Ⅳ and the obtained heterogeneous liver cells were then isolated and purified by density gradient centrifugation. The expressions of albumin and CK19 mRNA in hepatic oval cells were analyzed by immuno-fluorescence and RT-PCR. Results The survival rate of the newly isolated oval cells was more than 90%. The hepatic stem cells were shown by immuno-fluorescence of stem cell’s antigen c-kit. The expressions of mRNA CK19 and albumin of the oval cell were also detected by PCR. The proliferation activity of the newly isolated oval cells was significantly high and they could be induced to differentiate into both hepatic and bile ductal cells by some growth factors. Conclusion The successful development of the simple and feasible isolation and purification procedure as well as the identification method for hepatic oval cells may provide a fundamental for further studies about bionomics of the hepatic stem cell and the relation between stem cells and hepatic carcinoma.
Objective To make a comparative study on the effects of whole bone marrow culture method and density gradient centrifugation method in isolating hBMSCs. Methods hBMSCs were obtained from healthy adult volunteers and isolated by whole bone marrow culture method and density gradient centrifugation method. Primary cell morphology was observed using inverted phase contrast microscope and the cells in the 2nd passage were stained with HE after being cultured for 7 days. And then, the generation time of the primary, 2nd and 3rd passage hBMSCs was comparedbetween two methods and the surface markers were detected by flow cytometer. In addition, the ALP expression inosteoinductive hBMSCs were evaluated by ALP activity kit at 3, 6 and 9 days and ALP staining was used for osteoinductivehBMSCs with Kaplow method at 9 days. Results Primary cells isolated with whole bone marrow culture method showedaggregation growth while cells isolated with density gradient centrifugation method showed diffusion growth. HE stainingshowed no significant difference in the morphology of the 2nd passage cells between these two methods. The generationtime of primary cells isolated by whole bone marrow culture method (15.36 ± 1.67) days was significantly shorter than that of cells isolated by density gradient centrifugation method [(18.57 ± 1.05) days] (P lt; 0.01), while the generation time of the 2nd and 3rd passage cells showed no statistically significant differences between these methods (P gt; 0.05). The concent of positive surface markers (CD29, CD44, CD71, CD105, CD166) and negative surface marker CD34 in the 2nd cells showed no significant difference between these two isolation methods (P gt; 0.05); however, negative markers CD14 and CD45 showed significant difference (P lt; 0.01). The ALP expression in osteoinductive cells showed no statistical significant (P gt; 0.05) at 3, 6 and 9 days; and the ALP staining positive cell ratio of whole bone marrow culture method was basically in accordance with that of density gradient centrifugation method at 9 days. Conclusion hBMSCs could be isolated by whole bone marrow culture method, and the cell isolation effects of whole bone marrow culture method are equivalent with density gradient centrifugation method.
Objective To explore a simple, effective and stable method for the isolation and purification of Kupffer cells from rat liver, enabling further study on the structure and function of these cells in vitro. Methods After laparotomy, a catheter was inserted into the portal vein and secured with artery clamp. Then, the rat liver was perfused and digested with solution Ⅰ and solution Ⅱ containing 0.05% collagenase Ⅳ respectively. The cell suspension was centrifuged with isopycnic sedimentation in a two-step Percoll gradient to harvest Kupffer cells. The isolated Kupffer cells were purified by selective adherence after 30 min of cultivation, and identified by evaluation of phagocytosis of India ink and peroxidase staining with DAB through light and electron microscopy. Results It was verified that the viability of isolated Kupfffer cells was more than 90% through Trypan blue staining. Those Kupffer cells could attach to plastic quickly and phagocytose ink, and had the appearance of “fried eggs” in positive peroxidase staining with a purity of 95%. Under the light microscopy, the appearance of newly isolated Kupffer cells was round with uniform shape and size. After two days of culture, Kupffer cells appeared to distend with irregular or stellate shape. The typical features were observed in the transmission electron micrographs. There were numerous pseudopods and occasional cup-like indentations in the cell membrane of Kupffer cells. The cytoplasm contained numerous types of lysosomes and other phagocytotic vesicles. Conclusion The method for isolating and culturing Kupffer cells in this study is effective and stable, and the biological characters are preserved in the cultured cells.