中文摘要：

目的：探索RGD多肽修饰的改性PLGA支架材料上骨髓基质细胞的增殖、粘附及分化情况。方法用异型双功能交联剂Sulfo-LC-SPDP将GRGDSPC多肽共价结合到改性PLGA支架材料上，以未接多肽的改性PLGA材料做对照，取第三代MSC接种到材料上，培养1d、2d、3d、4d后比较材料上的细胞密度来反映细胞的增殖程度；取第三代MSC接种到材料上，培养4h、12h后沉淀法定量检测粘附的细胞数，培养24h后摄光镜图像比较粘附细胞的数量和形态，并用FITC连接的鬼笔环肽对细胞骨架染色，在荧光显微镜下观察细胞骨架的组织情况；取第三代MSC接种到材料上，用成骨性培养基培养7d、14d、21d，检测细胞中ALP活性来了解MSC分化情况。结果：培养1d、2d、3d、4d后细胞的增殖程度无显著性差异；培养4h、12h后实验组细胞粘附率均显著高于对照组，且24h后细胞的粘附质量、细胞骨架的组织情况也较对照组为好；培养14d后实验组细胞表达显著高的ALP活性。结论：RGD多肽修饰对细胞增殖无明显促进作用，但能提高改性PLGA支架材料对骨髓基质细胞的粘附性，对MSC向成骨细胞分化有显著促进作用。

英文摘要：

Objective： PLGA modified with RGD peptide was prepared, the proliferation, adhesion and differentiation of MSC on the scaffold was investigated. Methods A heterobifunctional cross-linker, Sulfo-LC-SPDP was used to immobilize GRGDSPC on the surface of PLGA. The third generation of MSC was seeded onto the RGD modified PLGA, incubated for 1d, 2d, 3d and 4d, the cell density was calculated and was used as index of cell proliferation. MSC was seeded onto the RGD modified PLGA, and incubated far 4h and 12h at standard condition, in each experiment the number of adhesive cells was counted to evaluate the efficiency of cell adhesion, and the photo of adhesive cells cultured for 24h was taken, then FITC-conjugated phalloidin was used to stain the cytoskeleton. The third generation of MSC was cultured on the RGD modified PLGA for 7d, 14d and 21d with osteogenic supplements, then their ALP activity was measured. Results： We found no significant difference in cell density between modified and unmodified PLGA for the culture of 1-4d. After 4h and 12h culture the efficiency of cell adhesion in the modified PLGA was higher than the unmodified PLGA. After 24h culture the quality of cell adhesion in modified PLGA was better than the control, and their cytoskeleton was more robust. At the end of 14d the cultured MSC on modified PLGA expressed higher ALP activity than that cultured on unmodified PLGA. Conclusion： RGD peptide enhanced cell adhesion to PLGA and promoted MSC differentiate to osteoblast, but no obvious effects were observed in cell proliferation.