脱细胞猪主动脉瓣膜与可降解聚合材料共同构建复合组织工程瓣膜

目的对新型复合组织工程瓣膜进行体外生物力学和动物体内移植试验，为临床应用过渡提供依据。方法以脱细胞猪主动脉瓣作为支架，用可降解聚合材料3-羟基丁酸与3-羟基己酸共聚酯（3一hydroxybutyrate—co-3-hydroxyhexanoate，PHBHHx）涂层，构建新型复合组织工程瓣膜。（1）复合组织工程瓣膜、新鲜猪主动脉瓣和脱细胞猪主动脉瓣各12枚，用单轴生物拉伸机进行体外生物力学测试；（2）小尾寒羊10只，其中5只在全身麻醉非体外循环下接受复合组织工程瓣膜，移植到羊的肺动脉瓣位；其余接受脱细胞猪主动脉瓣作为对照。术后18周处死动物，取出移植瓣膜，进行组织学、免疫荧光染色、扫描电子显微镜检查和钙含量测定。结果复合组织工程瓣膜保持了自然瓣形态，抗拉强度显著提高（P〈0．05）；瓣膜柔软，表面光滑无血栓；免疫荧光染色检测，瓣膜新生内膜中内皮细胞呈CD31阳性反应，沿瓣表面连续排列，间质细胞呈现单克隆鼠抗人平滑肌actin（sMA）阳性反应；复合组织工程瓣膜钙含量明显低于脱细胞猪主动脉瓣（P〈0．05）。结论复合组织工程瓣膜具有自然瓣膜的三维形态结构，良好的生物力学特性、生物相容性和细胞引导性，初步具备组织工程瓣膜雏形。

Decellularized Xenogenic Valve Scaffolds Coated with Biodegradable Polymer for Heart Valve Tissue Engineering

Objective To study and test novel hybrid valves in vitro and in vivo, and provide basis for clinical use in future. Methods The hybrid valves were fabricated from decellularized porcine aortic valves coated with poly (3-hydroxybutyrate-co-3-hydroxyhexanoate, PHBHHx).(1)In the mechanical test in vitro, the uniaxial tensile biomechanics test of the fresh (n=12), uncoated (n=12) and hybrid valve leaflets (n=12) were investigated. (2)In study in vivo, hybrid valves(n=5) implanted in pulmonary position in sheep ...