摘要
目的通过流体力学模型分析三维灌注培养条件下载体内细胞增殖与流场变化的关系。方法利用灌注型生物反应器对复合骨髓基质干细胞的β-TCP载体进行动态灌注培养,对不同时间段的载体行组织形态学观察和计量,建立灌注系统的流体力学模型,比较载体不同区域细胞增殖速度与流场的关系。结果细胞在β-TCP载体内增殖速度随培养时间的延长而增加。培养1周,大部分区域细胞大多呈单层排列;培养2周,部分孔道已填满了细胞。培养4周,大部分孔道被细胞填满,有些区域细胞数量减少。建立载体随机孔道结构的流体分析模型发现,细胞生长较快区域对应的流速大多在0.14～0.64 mm/s,剪切应力在0.0029～0.017 Pa。结论载体内流体环境(流体剪切应力和流速)影响细胞在载体各个部位的生长,细胞生长导致载体内连通流道的结构和大小发生变化,其流体微环境亦随着发生变化,设计有利于成骨转化的载体结构要考虑这一因素。
Objective To analyze the relationship between the cell proliferation and flow fields inside the β-tricalcium phosphate （β-TCP） scaffold with the computational fluid dynamics. Methods The β-TCP scaffolds combined with mesenchymal stem cells were perfused dynamically with a bioreactor for several weeks. The histological and morphometric studies were performed. The CFD modeling was established to reveal the relationship between the cell proliferation and the flow field. Results Histological study showed that the cells proliferated through the whole scaffold along with the time. The cells formed a continuous monolayer in the first week. Some pores were fully filled with cells after 2 weeks＇ culture. Most of pores were fully filled after 4 weeks＇ culture, while in some areas the cell coverage decreased. The CFD modeling showed that the optimal fluid velocity and shear stress for the cell proliferation were 0.14-0.64 mm/s and 0.0029--0.017 Pa respectively. Conclusion The microenvironment including the fluid velocity and shear stress had the effect on the cell proliferation inside the scaffold. The size of the interconnecting passages of the pores inside the scaffold changed during the cell proliferation. So did the microenvironment. These factors should be taken into account during the design of scaffold for bone tissue engineering.
出处
《医用生物力学》
EI
CAS
CSCD
2008年第1期52-56,共5页
Journal of Medical Biomechanics
基金
国际科技合作重点项目(2005DFA30120)
国家自然科学基金项目(30600629)
上海市科委资助项目(05DJ14005；054119564)
关键词
生物反应器
计算流体力学
骨髓基质干细胞
流场
Bioreactor
Computational fluid dynamics
Bone mesenchymal stem cells
Flow field
