组织工程心脏瓣膜体外脉动反应器的初步研制

目的:探讨自行研制的体外脉动反应器应用于组织工程心脏瓣膜应力预适应的可行性.方法:根据流体力学原理,采用特殊材料自行设计制作了体外脉动反应器和预适应应力培养系统;将生物瓣置于反应器中运转,观察生物瓣的工作状态和系统的稳定性.以脱细胞猪主动脉瓣作支架,新生牛主动脉内皮细胞作种子细胞构建组织工程心脏瓣叶,静态培养4 d后,置入反应器内进行预适应处理24 h(流量由30 ml/min调至400 ml/min,频率30次/min),观察内皮细胞残留情况,并与静态培养的瓣膜相比较.结果:预适应应力培养系统能产生搏动性液体流,生物瓣正常工作,运转7 d,系统状态稳定.静态培养成功构建组织工程心脏瓣膜,内皮细胞与瓣叶支架黏附紧密,沿瓣叶表面形成单层细胞层,生长状态良好;动态培养的瓣叶内皮细胞部分被冲刷脱落,但仍有少部分细胞(6.26％)残留黏附.结论:自行设计和构建的体外脉动反应器基本能模拟体内心脏瓣膜的血流动力学,用于组织工程心脏瓣膜预适应研究具有可行性.

Preliminary development of pulsatile reactor for tissue-engineered heart valve in vitro

Objective:To investigate the feasibility of applying self-developed pulsatile reactor in vitro in stress precondition of tissue-engineered heart valve. Methods:According to the principle of the hydrodynamics,we developed the pulsatile reactor with special materials and culturing system of precondition, then a bioprosthetic heart valve was put into the reactor to verify the working state and stability of precondition system. The tissue-engineered heart valve leaflet,developed by seeding newborn bovine aortic endothelial cells on decellularized porcine aortic valve leaflet,was subjected to precondition treatment for 24 h to observe the remnant endothelial cells(flows from 30 ml/min to 400 ml/min,frequency:30 beats/min). A tissue-engineered heart valve leaflet created in static condition was taken as control. Results: The system created the pulsatile flow through the valve. The bioprosthetic valve worked continuously for 7 d. In the static condition, a tissue-engineered heart valve leafket was created successfully. The endothelial cells expanded well, and formed a continuous monolayer on the surface. In the pulsatile condition, however,most endothelial cells on leaflet was brushed off. Conclusion:The pulsatile reactor in vitro can simulate the hydrodynamics of heart valve in vivo, and it is feasible for precondition study of the tissue-engineered heart valve.