骨形态发生蛋白-2与碱性成纤维细胞生长因子在异位和原位成骨中的作用

摘要

Objective We ascertained the effect of bone morphogenetic protein-2 (BMP-2) and basic fibroblast growth factor (bFGF) by a series of experiments: Proliferation and differentiation of bone marrow stromal cells (BMSCs) in vitro, ectopic and in situ bone formation and loaded porous calcium phosphate cement (CPC) on the repair of bone defects around dental implants. Methods BMSCs from Beagle dogs were cultured in vitro with basic culture medium containing BMP-2, bFGF, and BMP-2+bFGF. Proliferation and differentiation of BMSCs were quantified using methyl thiazolyl tetrazolium (MTT) and alkaline phosphatase GVLP) test. The CPC seeded with BMSCs and BMP-2, bFGF, com-bined BMP-2 with bFGF were implanted subcutaneously into nude rats in ectopic bone formation, and were implanted into critical-sized bone defects of Beagle dogs in the in situ bone formation. The hone formation was detected by his-tology examination and quantified using an image analysis system. Polychrome sequential fluorescent labels and fluores-cence histological examinations of undecalcified sections were performed post-operatively. Results It was determined that BMP-2+bFGF promoted BMSCs statistically significant proliferation and differentiation compared to either BMP-2 or bFGF in vitro. The CPC with BMP-2+bFGF group yielded more bone than those with either BMP-2 or bFGF in ectopic bone formation test. The percentages of newly ectopic formed bone were higher in the BMP-2+bFGF group(48/79%±1131%) than those in other groups (BMP-2 group, 30.71%±10.85%; bFGF group, 27.33%±9.67%; and the control group, 10.65%±6.05%). Undecalcified sections showed that new bone was actively formed in the BMP-2+bFGF group after 12 weeks in the in situ bone formation test. The bone mineralization apposition ate (MAR) was better in the BMP-2+bFGF group than in other groups (P<0.01). Conclusion BMP-2 combined with bFGF are more effective than one alone in promoting the formation of new bone.%目的 通过骨髓基质细胞(BMSCs)的体外增殖和分化、异位成骨和原位成骨实验来观察骨形态发生蛋白-2(BMP-2)和碱性成纤维细胞生长因子(bFGF)在成骨过程中的作用.方法 分别用含BMP-2、bFGF和BMP-2+bFGF的培养液体外培养Beagle犬的BMSCs,通过甲基噻唑基四唑(MTT)比色法测定细胞增殖水平,通过测定碱性磷酸酶(ALP)活性观察细胞的分化情况.将BMSCs与多孔磷酸钙(CPC)分别在含BMP-2、bFGF和BMP-2+bFGF的培养液中复合培养,制成复合材料,一部分植入裸鼠皮下,观察异位成骨情况,另一部分植入Beagle犬的种植体周围骨缺损区,经过荧光标记观察原位成骨情况.结果 含有BMP-2+bFGF的培养液促进BMSCs增殖和分化的能力最强.异位成骨情况:BMP-2+bFGF组的成骨量较其他组明显增加,其新骨形成百分比为48.79％±11.31％,高于单一BMP-2组(30.71％±10.85％)和bFGF组(27.33％±9.67％)以及对照组(10.65％±6.05％).原位成骨术后12周,BMP-2+bFGF组的矿化沉积率高于其他组,其差异有统计学意义(P＜0.01).结论 在促进成骨方面,BMP-2和bFGF共同作用优于单一因子.