中文摘要：

目的：研究Rab7过表达及失活突变（Rab7T22N）对CpG刺激的RAW264.7巨噬细胞中分泌细胞因子的影响。方法：采用RT-PCR和Real-time PCR检测RAW264.7细胞中Rab7在CpG刺激下表达模式。将Rab7真核表达质粒及失活突变质粒Rab7T22N通过脂质体法转染RAW264.7细胞,G418稳定筛选,Western法鉴定表达效果。用CpG刺激稳定表达Rab7的RAW264.7细胞系,RT-PCR和Real-time PCR检测细胞因子IL-6、IL-1β、IFN-β的表达量变化。结果：CpG刺激RAW264.7后,Rab7 mRNA表达水平逐渐增高,在8小时达到高峰,表达增高近4倍。Rab7过表达后,CpG刺激后产生的IL-6、IL-1β、IFN-β显著降低。巨噬细胞中Rab7失活突变后,在CpG刺激后IL-6、IL-1β、IFN-β的表达又显著增加。结论：CpG促进RAW264.7巨噬细胞中Rab7 mRNA的表达,Rab7抑制了CpG刺激的巨噬细胞中IL-6、IL-1β、IFN-β的表达,该抑制作用的发挥与其酶活性的GTP结合有关。该研究为进一步阐明Rab7在CpG/TLR9信号通路中的作用奠定了基础。

英文摘要：

Objective：To analyze the effect of Rab7 overexpression or overexpression of dominant negative mutant form of Rab7（Rab7T22N） on the production of cytokines in RAW264.7 macrophages induced by CpG.Methods：RT-PCR and Real-time PCR was used to measure the induced expression pattern of Rab7 in RAW264.7 cells stimulated by CpG.The eukaryotic expression vector of Rab7 and Rab7T22N were transfected into RAW264.7 cells by the methods of liposome,and screened by G418.The constant overexpression of Rab7 was verified by Western blot.The production of IL-6,IL-1β and IFN-β were measured with RT-PCR and Real-time PCR after transfected RAW264.7 cells were stimulated by CpG.Results：The Rab7 mRNA expression in RAW264.7 cells was gradually increased after stimulated with CpG,and the peak expression was at 8h,with about 4 times as much as the base expression.Overexpression of Rab7 inhibited CpG induced expression of IL-6,IL-1β and IFN-β in RAW264.7 cells.However,overexpression of Rab7T22N significantly promoted the expression of the above cytokines in RAW264.7 macrophages induced by CpG.Conclusion：CpG induced the expression of Rab7 mRNA in RAW264.7 cells.Rab7 inhibits the expression of IL-6,IL-1β and IFN-β in CpG stimulated Raw264.7 cells.The inhibition effect of Rab7 is associated with the enzyme activity of GTP-binding.The experiments may lay a foundation for further study of the role of rab7 in CpG/TLR9 signaling pathways.