骨形态发生蛋白-2活性多肽修饰的重组胶原矿化骨对骨髓基质干细胞生物学行为的影响

Effect of mineralized recombinant collagen bone modified with BMP-2-derived peptide on biological behavior of bone marrow stromal cells

目的探讨骨形态发生蛋白-2（BMP-2）活性多肽修饰的重组胶原矿化骨复合材料对骨髓基质干细胞（BMSCs）增殖、黏附及分化等生物学行为的影响。方法制备重组胶原矿化骨支架材料，将BMP-2活性多肽通过交联剂共价结合到材料上，扫描电镜观察支架材料表面微观形貌；取第3代BMSCs接种到材料上，以未结合多肽的重组胶原矿化骨作为对照，采用MTT法检测BMSCs在材料表面的增殖；沉淀法检测BMSCs在材料表面的黏附率；扫描电镜观察比较BMSCs在材料表面的生长形态；通过检测细胞中的碱性磷酸酶活性及钙含量，观察BMSCs在材料表面的分化情况。结果扫描电镜结果显示：支架材料呈多孔状；X射线光电子能谱法证实BMP-2活性多肽成功共价结合到材料表面；BMP-2活性多肽修饰的重组胶原矿化骨复合材料表面BMSCs的黏附和向成骨细胞方向分化能力均高于对照组，差异有统计学意义（P〈0．05），而BMSCs的增殖能力与对照组相比，差异无统计学意义（P〉0．05）。结论BMP-2活性多肽可以显著改善重组胶原矿化骨复合材料的细胞相容性和生物活性，经BMP-2活性多肽修饰的重组胶原矿化骨复合材料是一种理想的骨组织工程支架材料。

Objective To explore the effect of mineralized recombinant collagen bone modified with BMP-2-derived peptide on the adhesion, proliferation and osteogenic differentiation of bone marrow stromal cells （BMSCs）. Methods The mineralized recombinant collagen bone was prepared and the BMP-2-derived peptide was immobilized on the surface of scaffolds through a method of cross-linker. The microcosmic appearance of the scaffolds was observed by scanning electron microscopy. The third generation of BMSCs was seeded onto the scaffolds, using the unmodified mineralized recombinant collagen bone as control. The adhesion and proliferation of BMSCs were analyzed. The alkaline phosphatase activities and calcium content were measured. Results The scanning electron microscopy showed that the surface of scaffolds was porous. X-ray photoelectron spectrometry （XPS） confirmed that the BMP-2-derived peptide was immobilized on the surface of scaffolds successfully. The adhesion and differentiation into osteoblasts of the BMSCs were significantly greater than those in the control group （P 〈 0. 05 ）, but there was no significant difference between the experimental group and the control group in proliferation of the BMSCs （P 〉 0. 05 ） . Conclusion Since BMP-2-derived peptide can improve the biocompatibility and bioactivity of mineralized recombinant collagen bone, the mineralized recombinant collagen bone modified with BMP-2-derived peptide is a kind of ideal scaffold material for bone tissue engineering.