仿生支架材料骨形态发生蛋白7多肽/壳聚糖/纳米羟基磷灰石/胶原的制备及其细胞相容性

Preparation of bone morphogenetic protein-7 peptide/chitosan/nanometer hydroxyapatite/collagen biomimetic composite and its cytocompatibility

背景：目前骨组织工程常用的支架材料主要有无机材料、有机高分子材料及天然衍生材料等,上述材料各有优缺点,为了充分发挥各类材料的优势,弥补其不足,目前多采用联合材料制备复合支架。目的：制备新型仿生支架材料骨形态发生蛋白7多肽/壳聚糖/纳米羟基磷灰石/胶原,并观察其对骨髓间充质干细胞增殖、黏附及分化的影响。方法：制备壳聚糖/纳米羟基磷灰石/胶原复合支架材料,扫描电镜观察支架材料表面微观形貌;采用真空吸附法将骨形态发生蛋白7多肽与支架材料复合,高效液相色谱仪检测骨形态发生蛋白7多肽在体外的释放规律;将骨髓间充质干细胞接种到复合骨形态发生蛋白7多肽的仿生支架材料上,以未复合多肽的支架材料作为对照,检测支架材料表面细胞增殖、黏附率、生长形态及碱性磷酸酶活性。结果与结论：壳聚糖/纳米羟基磷灰石/胶原支架材料呈多孔状,孔径10~100μm;骨形态发生蛋白7多肽可以从支架材料中缓慢释出;在复合多肽的仿生支架材料表面,骨髓间充质干细胞的黏附及向成骨细胞方向分化能力均明显强于对照组（P〈0.05）,而增殖能力与对照组差异无显著性意义（P〉0.05）。说明新型仿生支架材料骨形态发生蛋白7多肽/壳聚糖/纳米羟基磷灰石/胶原是一种理想的骨组织工程支架材料,具有良好的细胞相容性。

BACKGROUND：The commonly used scaffold materials in bone tissue engineering are inorganic materials,organic polymer materials and natural derived materials,these materials have their advantages and disadvantages.In order to give full play to the advantages of various materials and make up for its shortcomings,composite materials are currently applied for the preparation of composite scaffold.OBJECTIVE：To prepare bone morphogenetic protein-7（BMP-7） peptide/chitosan/nanometer hydroxyapatite/collagen biomimetic scaffold,and to explore the effect of it on the adhesion,proliferation and differentiation of bone marrow stromal cells（BMSCs）.METHODS：The chitosan/nanometer hydroxyapatite/collagen composite scaffold was prepared,and the microcosmic appearance of the composite was observed by scanning electron microscope.The BMP-7 peptide was introduced into the composite by vacuum adsorption.The in vitro release of BMP-7 peptide from the scaffold was detected by using high performance liquid chromatography.The BMSCs were seeded onto the composite scaffold loaded BMP-7 peptide and the unloaded composites served as controls.The BMSCs proliferation,adhesion,growth morphology and alkaline phosphatase activities on the scaffold surface were analyzed.RESULTS AND CONCLUSION：The scaffold of chitosan/nanometer hydroxyapatite/collagen composite was porous at the pore size of 10-100 μm.The releasing character of BMP-7 peptide belonged to slow release.There was no significant difference on the proliferation of the BMSCs between the experimental group and the control group（P 0.05）,but the abilities of adhesion and osteogenic differentiation of the BMSCs in the experimental group were significantly greater than those in the control group（P 0.05）.BMP-7 peptide/chitosan/nanometer hydroxyapatite/collagen biomimetic composite scaffold is a kind of ideal scaffold materials for bone tissue engineering and has good biocompatibility.