纳米羟基磷灰石/壳聚糖/聚丙交酯支架的体外生物相容性和成骨活性

Biocompatibility and osteoinductive activity of nano-hydroxyapatite/chitosan/ poly(lactide-co-glycolide) scaffolds in vitro

背景:研究发现将聚丙交酯、纳米羟基磷灰石或聚丙交酯两两复合后可在一定程度上改善支架的机械性能、生物相容性和对细胞的成骨诱导分化,但离理想的骨组织工程支架材料尚有一定的距离。目的:对比不同配比纳米羟基磷灰石/壳聚糖/聚丙交酯支架的体外生物相容性及生物活性。方法:采用粒子沥滤法制备纳米羟基磷灰石、壳聚糖、聚丙交酯的质量比分别为10∶10∶80、10∶20∶70、20∶10∶70的复合支架。将3组复合支架与人骨髓间充质干细胞进行体外复合培养,绘制细胞在支架上的生长曲线,以RT-PCR检测细胞碱性磷酸酶活性和骨钙素的表达。结果与结论:配比为20∶10∶70复合支架的细胞黏附率明显高于其他两复合支架组(P<0.01),并且复合培养9-27 d的细胞碱性磷酸酶活性、复合培养15-27 d的骨钙素表达明显高于其他两复合支架组(P<0.01),3组细胞的增殖趋势相似。说明配比为20∶10∶70的纳米羟基磷灰石/壳聚糖/聚丙交酯支架具有良好的生物相容性及骨诱导活性。

BACKGROUND：Studies have found that combination of two of chitosan （CS）, nano-hydroxyapatite （nHA） and poly（lactide-co-glycolide） （PLGA） can improve the mechanical properties and biocompatibility of the composite stent in certain extent as wel as improve osteogenic differentiation of the cels, but there is a certain distance from the ideal bone tissue engineering scaffolds. OBJECTIVE：To study biocompatibility and osteoinductive activity of nHA/CS/PLGA scaffolds with different proportions in vitro. METHODS： nHA/CS/PLGA scaffolds were prepared at mass ratio of 10：10：80, 10：20：70, 20：10：70 respectively by particle leaching method. And human bone marrow stem cels （hBMSCs） were co-cultured with these scaffolds in vitro. Adhesion, proliferation, and osteoinductive activity of these scaffolds were examined qualitatively and quantitatively by growth curve of hBMSCs on scaffolds. Gene expression of alkaline phosphatase activity and osteocalcin was detected by RT-PCR. RESULTS AND CONCLUSION： hBMSCs could be attached, proliferated, and osteoinduced better on the nHA/CS/PLGA scaffold with the mass ratio of 20：10：70, compared to the other two groups of scaffolds. The differences were significant statisticaly （P〈 0.05）. Alkaline phosphatase and osteocalcin expressions were respectively higher in the scaffold with the mass ratio of 20：10：70 after 9-27 days of co-culture and 15-27 days of co-culture, in comparison with the other two groups of scaffolds. These findings indicate that the nHA/CS/PLGA scaffolds with the mass ratio of 20：10：70 demonstrated preferable biocompatibility and osteogenic inductivity, which is expected to be a promising scaffold material for bone tissue engineering.