联合应用重组人骨保护素和阿伦膦酸钠抑制成熟破骨细胞的体外实验研究

目的研究联合应用重组人骨保护素(rhOPGFc)和阿伦膦酸钠(ALN)对破骨细胞抑制作用。方法进行人类OPGFc融合蛋白毕赤酵母表达株的构建和鉴定。酶消化法获取新生小鼠颅骨成骨细胞,与破骨细胞前体细胞RAW264.7按照4∶1比例混合,培养于96孔板中。9d后,重酒石酸盐抗酸性磷酸酶染色(TRAP染色)鉴定后,分别使用10-5g/LrhOPGFc、10μmol/LALN、10-5g/LrhOPGFc+10μmol/LALN、5×10-6g/LrhOPGFc+5μmol/LALN作用于混合细胞体系,并设空白对照。加药后3、7d观察破骨细胞数目和形态,计算单位面积内TARP阳性细胞个数,并行骨磨片吸收陷窝计数。结果重组人骨保护素(rhOPGFc)分子量与预期结果相符合,蛋白印迹检测(Westernblotting)显示,该条带可被抗免疫球蛋白IgG抗体别显色。小鼠成骨细胞与破骨细胞前体细胞RAW264.7混合培养后9d,体系中出现大量多核成熟破骨细胞,TARP染色证实为成熟破骨细胞。加药3、7d后,与对照组相比,其余各组破骨细胞TARP阳性细胞个数,骨磨片吸收陷窝计数均明显减少,以10-5g/LrhOPGFc+10μmol/LALN组减少最为显著。结论重组人骨保护素(rhOPGFc)可以有效减少成熟破骨细胞数目并抑制其功能。联合应用rhOPGFc和阿伦膦酸钠可以交互抑制成熟破骨细胞功能。

In vitro study of combination rhOPG-Fc and alendronate on inhibition osteoclast

OBJECTIVE: To study the effect of combination rhOPG-Fc and alendronate on mature osteoclasts. METHODS: Recombinant human osteoprotegerin secretory expression in P. pastoris was performed. Osteoblasts were got from new born mouse skeletal bone and proved by ALP staining and incubated together with osteoclasts precursor cell line Raw 264.7 in 96 well plate. After 9 d, 10 micromol/L ALN, 10(-5) g/L rhOPG-Fc, 10 micromol/L ALN + 10(-5) g/L rhOPG-Fc, 5 micromol/L ALN + 5 x 10(-6) g/L rhOPG-Fc were added to these coculture systems. Osteoblasts cultured without the drugs mentioned above served as controls. TRAP stain positive cells counting and cortical bone pit formation counting were preformed in the following the 3rd and 7th d. RESULTS: SDS-PAGE and Western blot showed that molecular weight of the expressed protein was about 55 KD, and it could reach specifically with anti-IgG antibody. Many multi-nuclear TRAP stain positive cells were found in the coculture control group after 9 d incubation, and proved to be mature osteoclasts by TRAP stain. In the 3rd and 7th d after the addition of rhOPG-Fc, ALN or both, TRAP stain positive cells counting and cortical bone pit formation counting decreased significantly in the rhOPG-Fc, ALN or both groups than in the control group, and the combine group (10(-5) g/L rhOPG-Fc + 10 micromol/L ALN) decreased most significantly when compared with rhopG-FC or ALN single. CONCLUSIONS: rhOPG-Fc can decrease the number of osteoclasts and inhibit their function. The combination of both rhOPG-Fc and ALN shows the significant inhibition effect on mature osteoclasts.