人重组白细胞介素-6对成牙骨质细胞的生长及分泌骨钙素能力的影响

Effect of recombinant human interleukin-6 on growth and osteocalcin producing ability of cementoblasts

目的 :了解rhIL 6对成牙骨质细胞 (cementoblasts,CBs)增殖活性及分泌骨钙素 (osteocalcin ,OC)能力的影响。方法 :试验所用的CBs为用组织块法联合酶消化法培养所得的新生牛CBs。实验组培养液为 10 % (体积分数 )FCS +RPMI16 40加不同 (质量 )浓度的rhIL 6 ,对照组不加rhIL 6。采用四甲基偶氮唑盐 (MTT)法观察CBs生长及存活状态 ;放射免疫分析法测定CBs培养上清液中OC的含量。结果 :rhIL 6对CBs的生长有抑制作用 ,并呈剂量依赖趋势 ,但无统计学意义 (P >0 .0 5 ) ;同一 (质量 )浓度rhIL 6在不同的培养时间段对CBs分泌OC的影响不同 ,除 0 .1μg·L- 1 IL 6组外 ,1、10、10 0 μg·L- 1 组上清液中的OC浓度在最初的 5d内有明显增高 ,以 10 0 μg·L- 1 组最显著 ,呈浓度依赖性 ,但在第 7天时 ,10 0 μg·L- 1 组的OC浓度明显下降至仅略高于第 3天的水平。 0 .1、1和 10μg·L- 1 组在第 3天和第 7天时 ,OC浓度均低于空白对照组。结论 :IL 6可能通过调节CBs的生长和OC的分泌而在CBs的代谢及牙骨质的形成、修复中发挥一定的作用。

Objective: To study the effect of rhIL 6 on the growth and osteocalcin (OC) production of cementoblasts (CBs). Methods:Cementum of newborn bovine teeth were harvested,cultured,and manually dissected, fragmented, and digested twice with 1 g·L -1 typeⅠcollagenase, CBs were harvested cultured,and identified as CBs by the positive staining to cementum attatchment protein (CAP) monoclonal antibody, which is specific to bovine CBs. The CBs in the experiment group were grown in 10% (volume fraction) fetal calf serum (FCS)+RPMI1640, supplemented with various concentrations of rhIL 6. The control groups were grown in 10%FCS+RPMI1640. To assess the growth and OC producing ability, the CBs were grown in 96 well and 24 well plates, respectively. The growth of CBs was assessed by MTT method. The OC producing ability of CBs was examined with radioimmunoassay by measuring the osteocalcin (OC) in the supernatant liquid of CBs cultures. Results: The rhIL 6 displayed a trend of suppressing the growth of CBs in a dose dependent manner. However, this did not reach a significant level ( P >0.05). In addition, rhIL 6 at concentrations above 1 μg·L -1 , especially 100 μg·L -1 induced significantly more secretion of OC by CBs in a dose dependent manner during the first 5 days ( P <0.05). After that stage the concentration of OC decreased dramatically. An inhibition of OC production was observed at 3rd and 7th day when CBs were cultured in the presence of rhIL 6 at concentrations between 0.1, 1 and 10 μg·L -1 . Conclusion: These results suggested that IL 6 may be involved in the process of cementum formation and repair by influencing the growth and OC producing ability of CBs.