中文摘要：

目的 探讨新型含精氨酸-甘氨酸-天冬氨酸（RGD）肽K16RGDSPC修饰聚丙交酯-CO-乙交酯（PLGA）-[ASP-PEG]支架材料对骨髓基质干细胞（BMSCs）在其表面黏附、增殖及成骨分化的影响。方法 固相合成法合成K16GRGDSPC并通过质谱仪和高压液相色谱进行鉴定。用交联剂Sulfo-LC-SPDP将K16GRGDSPC接枝到PLGA-[ASP-PEG]支架材料上，通过XPS图谱检测接枝反应的发生。将改性后的PLGA-[ASP-PEG]支架材料与兔BMSCs在成骨诱导培养基中复合培养，以未改性的支架材料作对照。通过沉淀法、微管吮吸法、MTT法和考马斯亮蓝法分别检测BMSCs的黏附和增殖性能的变化；应用碱性磷酸酶（ALP）试剂盒检测BMSCs的ALP表达水平并通过RT-PCR检测细胞ALP、骨钙素（OCN）、骨桥蛋白（OPN）和Ⅰ型胶原的表达，通过免疫荧光染色检测核心结合因子a1（Cbfal）表达，观察BMSCs向成骨细胞方向分化的情况。结果 XPS图谱证实含RGD肽K16GRGDSPC被成功地接枝到PLGA-[ASP-PEG]表面。复合BMSCs培养结果表明，改性后的PLGA-[ASP-PEG]表面BMSCs的黏附性能和增殖能力明显提高，而且其成骨标志物（ALP、OCN、OPN、Ⅰ型胶原和Cfba1）的表达均显著高于对照组（P〈0．05）。结论 含RGD肽K16GRGDSPC能促进BMSCs在骨基质材料表面的黏附、增殖并诱导其向成骨方向分化。

英文摘要：

Objective To explore the effects of synthetic RGD-eontaining peptide K16GRGDSPC covalent bonding with PLGA-[ ASP-PEG ] scaffold materials on the adhesion, proliferation and osteogenic differentiation of rabbit bone marrow stromal cells （BMSCs）. Methods The peptide was synthesized by solid-phase synthesis method and characterized by mass spectrometry and high pressure liquid chromatography. PLGA-[ ASP-PEG] scaffold materials were modified with the piptide by cross linker Sulfo- LC-SPDP and detected by XPS. The BMSCs obtained from rabbit were cultured on PLGA-[ ASP-PEG] modified with the peptide and those cultured on unmodified PLGA-[ ASP-PEG] were also observed as control group. The adhesion and proliferation behaviors of the cells were analyzed by conventional precipitation method, micropipette aspiration technique, MTT assay and Coomassie Brilliant Blue dyes. The osteogenic differentiation of the cells was showed by the activity of alkaline phosphatase （ALP） assayed by ALP Assyay Kit and the mRNA levels of ALP, osteocalcin（ OCN）, osteopontin（OPN） and collagen Ⅰ assessed by realtime PCR（RT-PCR）. Immunofluorescence stain was also used to detect the expression of core binding factor al （CAbal） which was an osteogenic maker as well. Results The peptide was successfully manufactured and linked to the surface of the PLGA-[ ASP-PEG ] by the cross-linker. The abilities of adhesion and proliferation and the expressions of osteogenic makers of the cells were significantly higher than those of control group （P 〈 0. 05 ）. Conclusion RGD-containing peptide K16GRGDSPC could promote the adhesion, proliferation and osteogenic differentiation of BMSCs on the biomimetic bone-matrix materials.