生物活性玻璃修饰聚对苯二甲酸乙二醇酯对骨愈合的影响

Bioactive glass modified polyethylene terephthalate promotes bone healing

背景:聚对苯二甲酸乙二醇酯人工韧带材料具备优良的力学性能,但其生物相容性有待提高。目的:观察生物活性玻璃修饰聚对苯二甲酸乙二酯对骨愈合的影响。方法:1体外实验:将聚对苯二甲酸乙二酯(对照组)、生物活性玻璃-聚对苯二甲酸乙二酯复合物(实验组)分别与MC3T3-E1细胞共培养,培养3 d后,观察细胞形态;培养1,3,5 d后,检测细胞增殖及碱性磷酸酶活性;2体内实验:取24只新西兰大白兔,制备单侧膝关节韧带断裂模型,随机分为2组,实验组置入生物活性玻璃-聚对苯二甲酸乙二酯复合物,对照组置入聚对苯二甲酸乙二酯。置入后6,12周,对比移植部位生物力学及组织学变化。结果与结论:1体外实验:培养3 d后,实验组细胞密度显著高于对照组;实验组培养3,5 d的细胞增殖及碱性磷酸酶活性显著性高于对照组(P<0.05);2体内实验:实验组置入后6,12周的最大轴向拔出力显著大于对照组(P<0.05)。置入后6周,对照组存在明显缺损,且缺损部位存在大量炎性细胞;实验组新骨形成界面形成骨小梁,瘢痕组织较少,界面宽度狭小。置入后12周,对照缺损部位模糊,存在明显炎性细胞,骨面上存在新骨;实验组缺损部位存在较多的新生组织,缺损部位可见少许炎性细胞;3结果表明:生物活性玻璃修饰的聚对苯二甲酸乙二醇酯具有良好的细胞相容性、生物力学,可促进骨愈合。

BACKGROUND： Polyethylene terephthalate（PEA） holds good mechanical properties, but its biocompatibility needs to be improved.OBJECTIVE： To investigate the effect of bioactive glass modified PEA on bone healing. METHODS： In vitro experiment： PEA（control group） and bioactive glass modified PEA（experimental group） were respectively co-cultured with MC3T3-E1 cells. The cell morphology was observed at 3 days of culture, and the cell proliferation and alkaline phosphatase activity were detected at 1, 3 and 5 days of culture. In vivo experiment： 24 New Zealand white rabbits were enrolled, modeled into unilateral knee ligament rupture, and then randomly allotted to two groups. Bioactive glass modified PEA and PEA were implanted into experimental and control groups, respectively. Biomechanics and histological changes were compared between groups at 6 and 12 weeks after transplantation. RESULTS AND CONCLUSION： In vitro experiment： the cell density in the experimental group was significantly higher than that in the control group after 3-day culture（P〈0.05）; the cell proliferation and alkaline phosphatase activity were significantly higher than those in the control group at 3 and 5 days of culture（P〈0.05）. In vivo experiment： the maximum axial pull-out strength in the experimental group was significantly greater than that in the control group at 6 and 12 weeks after implantation（P〈0.05）. In the control group, the defect was obvious and there were a large number of inflammatory cells at 6 weeks after implantation; the defect region became fuzzy, abundant inflammatory cells existed and new bone formed on the surface at 12 weeks after implantation. In the experimental group, there were newly formed bones and trabeculae formed on the interface, the scar tissue became less, and the interface width was narrow at 6 weeks after implantation; numerous new tissues were observed, and only a few inflammatory cells observed in the defect region at 12 weeks after implantation. These results indicate that the modified PEA with bioactive glass possesses good biocompatibility and biomechanics, which can promote bone healing.