| Background It has be shown that Liver function failure,Hepatitis and Hepatocarcinoma threaten human health, hepatocytes transplatation and the whole-liver transplantation can help patien to get through the crucial period temporarily , but its application is still limited for organ availability, immunologic rejection and expensive operation cost . The new field of Engineering Liver Regeneration brings together for the first time the scientific disciplines of biology, materials science and biomedical engineering directed towards long-term repair and replacement of failing human liver, to inaugurate a new aera for the treatment of liver diseases . Living cells are harvested, grown in the laboratory, and stimulated to form liver tissues that mimic the complex structures and physiological behaviour of natural tissues. The study of Liver Tissue Engineering is including the study of seed cells, extracellular matrix and the rebuild of organ. To select ideal seed cells is the basic work of all researches. More and more scientists are paying close attention to select stem cell as seed cells, especially self-stem cells. It has been indicated that bone marrow has multipotential progenitor cells which can differentiate into skeletal muscl, cartilage, bone, liver, lung, brain, spleen ,cardiac muscle and tenden. It is well-known that there are two major kinds of stem cell in the bone marrow : Hematopoietic stem cell (HSCs)and Mesenchymal stem cells(MSCs).Msenchymal stem cells are a population of pluripotent cells,they can differentiate into bone , cartilage, lipocyte, skeletal myscle and liver.The multipotential of MSCs,the easy isolation and culture property,as well as their high ex vivo expansive potential makes these cells become an attractive seed cells of Engineering Liver Regeneration. Mesenchymal stem cells (MSCs) are a type in marrow, similar to fibroblast cells. There is no MSCs specificability monoclonal antibody so far, and so, MSCs can be isolated single marrow cell with 1.073g/mL Percoll, removed the suspending blood cells in the culturing medium. The MSCs are prone to be attached to the wall. Further expanded culturing on MSCs makes high purity and uniform morphology MSCs. Checking by flow cytometry found that MSCs didn't express CD34, CD11b, CD11a, CD71,CD31and CD45. The attached molecules CD44(HCAM) and CD29 , CD90 were positive, hinting that MSCs were marrow non-hematopoietic stem/progenitor cells, not hematopiesis stem cells, which were similar with previous study[7]. There has been a deeper research in using MSCs repairing the injury of bone , cartilage and tendon. For studying the condition and mechanism of MSCs differentiating into hepatocyte just begin,there are a series of difficulties in it. Such as :how to mimic microenvironment to induce MSCs differentiating into hepatocytes; how to improve the differentation rate;and how to set up perfect system of amplification. In addition, hepatocytes need to combine the material of Membrane to exert physiological function fully. In order to provide the cells the basic condition to exert physiological function,to select an ideal extracellular matrix to replace the Membrane ex vivo is a crucial problem. In this experiment,we study the condition and mechanism of MSCs differentiating into hepatocytes,to discuss the possibility of MSCs as seed cells of tissueengineering,on the other hand, we use different extracellular matrix to mimic Membrane,to observe the effect of extracellular matrix to differentiation rate, we also investigated the effect of partial hepatectomy to mesenchymal stem cells differentiating into hepatocytes, and the final aim is to discuss the mechanism of improving the differentiation rate Objective â‘ To explore the method for isolation, cultivation and expansion of mesenchymal stem cells from mouse bone marrow for offering an experimental foundation for the further differentiation and actual application. â‘¡ To explore whether mouse bone marrow mesenchymal stem cells has the potential ability to induced into hepatocytes. â‘¢ To study the...
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