利用人骨髓基质干细胞构建组织工程心脏瓣膜的体外实验

Reconstruction of tissue-engineered heart valve with human bone marrow stromal stem cells in vitro

BACKGROUND:Nowadays, mechanical or biological valve recipients used in the clinic are still at the risk of infection, hemorrhage, thrombosis and reoperation owing to valve stenosis. Tissue-engineered heart valve with biological activity can overcome the disadvantages above. While, the optimal choice of scaffolds and seeding cells remains disputable.OBJECTIVE:To explore the feasibility to construct tissue-engineered heart valve with acellularized porcine aortic valve scaffold and human bone marrow stromal stem cells in vitro.METHODS:The porcine aortic valves were decellularized with the detergent and enzymatic extraction process to remove the cellular components. Human bone marrow stromal stem cells were aspirated from sternum of the patients with simple congenital heart malformation, and then the cells were seeded on the acellularized porcine aortic valve scaffold and cultured for 5 days.RESULTS AND CONCLUSION:Flow cytometry identified that the characteristics of surface antigen of the inoculated seed cells were in line with those of human bone marrow stromal stem cells. Light microscopy and electron microscopy confirmed that the cellular components in the porcine aortic valves could be removed to obtain the complete acellular fiber mesh stent. There was no significant difference in biomechanical property between before and after acellularization. The human bone marrow stromal stem cells implanted on the acellularized porcine aortic valve scaffold could form a continuous cell layer on the surfaces of the scaffold. The inoculated bone marrow stromal stem cells could be differentiated into fibroblasts. The implantation of human bone marrow stromal stem cells on the acellularized porcine aortic valve scaffold can construct the tissue-engineered heart valve.