| Valve replacement is a effective therapeutic procedure for Cardiac valvular disease in human being,however the presentive bioprosthetic valve have no ignoriable shortcoming: Mechanical valves associated with a potential risk of thromboembolism require life-long anticoagulation;. Bioprosthetic valves are far less durable and are subject to calcification and progressive tissue deterioration. Homograft valves also have a limited resources and durability. None of available valve replacements has the capacity for growth and repair. the tissue engineered heart valve (TEHV ) is an new ideal valvular substitute that plants autologous seed cells on degradiable scaffords and seeds can grow and produce extracellular matrix(ECM) and formimg a alive valve day by day accroding to the principles and methods of engineering and the life science.It can restore and maintain the the valvular function. Tissue engineered heart valve have good histocompatibility, long durability, no immunogenecity and no need for anticoagulation. They have the ability for growth and repair.Seed cells is the first of all of tissue engineered heart valves.Vascular interstitial cells was investigated firstly owning to its circumstance similarity to heart valve interstitial cells,however its primary cell culturing is rather complex and need to sacriface a whole vessel.Bone- marrow mesenchymal stem cells(BMSCs) whose obtaining is easy ,proliferation quickly and immunogenecity little are applied to construct tissue engineered heart valve as a seed cells. In this study,the feasibility of inducement and differentiation of BMSCs to heart valve interstitial cells and those of using both induced BMSCs and vascular interstitial cell as seed cells were investigated.Part 1: Adult canine bone marrow mononuclear cells were separated by gradient centrifugation on Percoll methods , the BMSCs were obtained when mononuclear cellsh have been adheresive incubated and cell phenotype were identified by immuohistochemistry staining. BMSCs were commitedly induced by conditioning culture medium , The induced-BMSCs were freezed and preserved and resuscitated after 7 days to observe the cell growth, proleferation and function. Results : BMSCs obtain from The bone marrow mononuclear cells separated by Percoll after attached culture which were positive expression of α-SMA, Vimentin, and Negative expression of CD34, and laminine.About (50 ± 3)% induced BMSCs were positive expression of Laminin. Approximately (85 ± 3) % freezed induced-BMSCs could be resuscitated and preservedits capacity of growth, proleferation and function were well.it was demostrated that BMSCs induced which have already character of heart valve interstitial and higher resuscitation rate were a suitable seed cells.Part2: The canine saphenous was sectioned and its interstitial cells were cultued by tissue piller.the biological characteristic and cell phenotype of vascular interstitial cells were observed. The induced BMSCs were investigated in cell morphology, proliferation capability,collagen-synthesized capability and adherance to detergent acellularized porcine valves compared to venous mesenchymal cells.At the same time,the capability of cell resuscitating was studied between two kinds of mesenchymal cells. Results: both kinds of cells were uniformly adhensive growth, spindle-like cells.the double time of induced BMSCs was about 38h and that of venous mesenchymal cells was about 36h.There were no significant difference in collagen-synthesized capability and cell resuscitating rate however there were...
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