人骨髓基质干细胞构建组织工程心脏瓣膜的研究

Creation of tissue engineering heart valve from human mesenchymal stem cells

目的探讨人骨髓基质干细胞种植在去细胞猪主动脉瓣叶上体外构建组织工程心脏瓣膜的可行性。方法经1%TritonX100、0.01%胰酶0.02%EDTA、DNaseI及RNaseI处理制备去细胞猪主动脉瓣叶支架,测定瓣叶去细胞前、后的生物力学特性;人骨髓基质干细胞体外分离、培养、扩增后种植在去细胞瓣叶表面,观察细胞生长情况。结果猪主动脉瓣叶去细胞后获得完整无细胞的纤维网状支架,瓣叶去细胞前、后的断裂强度和断裂伸长率差异无统计学意义(P>0.05);体外培养的人骨髓基质干细胞(MSCs)在去细胞瓣叶表面形成一层基本连续的细胞层。结论去除细胞成分的猪主动脉瓣叶组织是一种良好的纤维支架,可以用于构建组织工程心脏瓣膜;人骨髓基质干细胞种植在去细胞猪主动脉瓣叶上构建组织工程心脏瓣膜是可行的。

Objective To investigate the feasibility of creating tissue engineering heart valve from human mesenchymal stem cell (MSCs) as an alternative cell source.Methods The porcine aortic valve leaflets were acellularized by using 1% Triton-X 100,0.01% trypsin-0.02% EDTA,DNase I,RNase I.Biomechanical characteristics of fresh valves and acellularized valves were tested.Human MSCs were isolated,cultured and expanded in vitro,frequently seeded onto the acellularized scaffolds.Their growth was observed.Results The acellularization procedure resulted in complete removal of the cells in valve leaflets while there was no significant difference in destroying stress (g/mm^2) and destroying stress ratio (%) between them (642± 125 vs 636±130, 54±12 vs 57±13, P> 0.05).The matrix could be successfully seeded with expanded human MSCs in vitro,which formed a continuous monolayer on the surface.Conculsion Acellularized porcine aortic valve can be applied as a scaffold to creat tissue engineering heart valve.Generation of functional tissue engineering heart valve from human MSCs was feasible.