完全脱钙松质骨的生物学特性(英文)

Biological characteristics of fully demineralized cancellous bone matrix

背景：脱钙松质骨被认为是一种“理想”的软骨组织工程支架材料已被广泛应用，但对其某些生物学特征目前仍不是十分清楚。目的：体外观察脱钙骨基质的降解性能、孔隙率以及骨髓间充质干细胞和脱钙骨基质的黏附性。设计、时间及地点：体外观察实验，分别于2005-01-08/04-15在兰州大学骨科研究所和2007-08-01/11-15在桂林医学院中心实验室进行。 材料：取青紫兰兔四肢骨干骺端及椎体松质骨，采用Urist提供的方法制作脱钙骨基质。方法：将脱钙骨基质置于磷酸盐缓冲溶液中测定其降解率；用液体置换法测其孔隙率；用细胞计量法测定生长良好的浓度为1× 108 L-1的第3代骨髓间充质干细胞与脱钙骨基质的黏附率。主要观察指标：脱钙骨基质的降解率、孔隙率及骨髓间充质干细胞与脱钙骨基质的黏附率。结果：脱钙骨基质的降解随时间的延长逐渐加速，完全降解需要10-12周；所测孔隙率为（77.15±3.44）%；浓度为1×108 L-1的第3代骨髓间充质干细胞与脱钙骨基质具有较高的黏附率（平均为71.25%）。结论：脱钙骨基质的降解曲线和骨髓间充质干细胞的增殖曲线相一致，具备良好的孔隙率和黏附率，提示脱钙骨基质可能为软骨组织工程比较理想的生物支架材料。

BACKGROUND： As an ideal scaffold of cartilage tissue engineering, demineralized bone matrix （DBM） has been widespread used. But some of biological characters remain poorly understood. OBJECTIVE： To determine the degradation capacity, interval porosity and adhesion rate of mesenchymal stem cells （MSCs） onto DBM in vitro. DESIGN, TIME AND SETTING： An observation experiment in vitro was complicated in Institute of Orthopedics, Second Hospital of Lanzhou University from January 8th to April 15th in 2005 and Central Laboratory of Guilin Medical University from August 1st to November 15th in 2007. MATERIALS： One chinchilla rabbit was killed under anesthesia. Referring to the method described by Urist, DBM was made by cancellated bone harvested from metaphysis and vertebral body METHODS： DBM was soaked into phosphate buffered solution to determine its degradation capacity; liquid replacement method was used to test its interval porosity; The 3rd passage MSCs at a concentration of 1×108/L were cocultured with DBM in vitro and adhesion rate of MSCs onto DBM was tested using cytometry. MAIN OUTCOME MEASURES： The degradation capacity, interval porosity and adhesion rate of MSCs onto DBM. RESULTS： The degradation rate of DBM was accelerated with the prolonging of time, and the complete degrading time was about 10-12 weeks; The holing rate tested was （77.15±3.44）%; The 3rd passage cells had a higher adhesive rate of 71.25% onto DBM. CONCLUSION： DBM degradation curve is consistent with MSCs proliferation curve, indicating a satisfactory adhesion capacity and interval porosity and DBM is an ideal biological scaffold material for cartilage tissue engineering.