BMP对异种骨移植局部TNF-α和IL-6基因表达的调节

The modulation of BMP on expression of TNF-α and IL-6 gene in the area of implanted xenogeneic bone

目的 观察骨形态发生蛋白 (BMP)在异种骨移植局部对 TNF-α和 IL - 6 m RNA表达的调节作用 .方法 将含有一定抗原性的牛松质骨载体与不同剂量的牛 BMP复合 ,植入小鼠股部肌袋 ,于术后 5 ,1 0和 2 0 d取材 ,制备石蜡切片 ,采用核酸分子原位杂交的方法 ,定性定位检测植骨局部 TNF-α和IL - 6 m RNA表达情况 ,通过图像分析 ,确定 TNF-α和 IL - 6m RNA表达强度 ,分析植骨局部不同计量 BMP对 TNF- α和IL- 6 m RNA表达的影响 .结果 植骨术后 5 ,1 0和 2 0 d,各组植骨局部均检测到 TNF-α和 IL - 6 m RNA阳性表达 ,以单纯载体组表达最强 ,高剂量 BMP组表达最弱 ,P<0 .0 1 ;牛松质骨载体中复合的 BMP对植骨局部 TNF- α和 IL- 6 m RNA表达有抑制作用 ,其表达抑制程度与 BMP呈剂量依赖关系 .结论 外源性 BMP在异种骨移植局部对 TNF-α和 IL - 6 m R-NA表达有抑制作用 ,提示 BMP在植骨局部具有诱导成骨和免疫调节双重作用 .

AIM To investigate the effect of Bone morphogenetic protein (BMP) on tumor necrosis factor α (TNF α) and interleukin 6 (IL 6) mRNA expression in the area of implanted xenogeneic bone. METHODS The particles of bovine cancellous bone with some antigenicity were combined with different amount of bovine BMP and implanted in the mouse's muscle pouch. Harvested 5, 10, and 20 days after implantation, the specimens were processed to determine the mRNA expression of TNF α and IL 6 by a nonradioactive in situ hybridization technique. The influence of BMP on the gene expression of the two cytokines was analyzed. RESULTS 5, 10 and 20 days after implantation, the expressions of TNF α and IL 6 gene were positive in the surrounding tissues. It was found that the expressions were markedly lower in the group combined with higher BMP content compared with the group combined with lower BMP content and the group with no combined with BMP ( P <0.01). Bovine cancellous bone carrier in combination with BMP exerted an inhibitory effect on the expression of TNF α and IL 6 at the site of implantation, showing a dose dependent curve of inhibition in relation to BMP content in the composite graft. CONCLUSION: Our findings indicate that the exogenous BMP possesses an inhibitory effect on the expression of TNF α and IL 6 mRNA, suggesting that BMP may be involved in both the modulation of cellular immunity and the induction of osteogenesis in the region of implanted xenogeneic bone.