生物反应器的设计与组织工程肌腱的构建

Bioreactor design and construct tissue engineered tendon

目的设计一套生物反应器,能构建具有较好形态和机械力学性能的肌腱组织。方法根据肌腱细胞体内的生物和力学环境,建立了细胞和可降解材料复合物的力学模型,设计了一套能够模拟体内力学环境的生物反应器,采用鸡肌腱为种子细胞培养扩增后接种于聚羟基乙酸(PGA)材料上,形成细胞-材料复合物并置于反应器中培养。设静态培养对照组,通过实验取材进行大体观察、组织学和生物力学检测。结果生物反应器能够构建出具有一定组织结构和机械强度的肌腱。检测结果显示恒定交变应力作用下培养的肌腱优于静态培养的肌腱组织。结论细胞和可降解材料复合物的力学模型具有一定的正确性,通过分析也存在某些局限性;应力作用下可以促进肌腱细胞基质的分泌,蠕变特性成为促进胶原定向排列的重要因素。

Objective TO design a set of bioreactor which can construct well morphological and mechanical performance tissue engineered tendons. Methods According to the biomechanics and environment of tendon exist in vivo, a model for compound of cells and biodegradable material was set up and a set of bioreactor which can simulate biomechanical environment was designed. Avian tendon celI-PGA sheets were cultured in dishes during the first two weeks. The constructs that received cyclical stretch served as experimental group, while unloaded constructs served as control group. Specimens were harvested for gross examination, H＆E staining and biomechanical test. Results Tendon like tissue can be got under continuous and pulsatile mechanical during the cell culture in vitro. From evaluations better results was proved in experimental group than control group. Conclusions mechanical model has both correctness and some limits. Stress can accelerate cell matrix secret. Viscoelastic material, such as compound of cell and biodegradable material, has instantaneous deformation by unvarying stress and strain increase linearly with time. Creep play an important role in collagen fibril parallel arrangement.