小鼠巨噬细胞内表达结核分枝杆菌CFP10-ESAT6融合蛋白对细胞增殖和凋亡的影响  

Effects of intracellular expression of Mycobacterium tuberculosis CFP10-ESAT6 fusion protein on proliferation and apoptosis of mouse macrophages

作　　者：任琳[1] 李轶[1] 王山梅[1] 师娟[1] 郭思[1] 

机构地区：[1]河南省人民医院感染控制科、细菌室,河南郑州450000

出　　处：《中国病理生理杂志》2013年第10期1809-1814,共6页Chinese Journal of Pathophysiology

基　　金：河南省医学科技攻关计划普通项目(No.201203094)

摘　　要：目的:建立培养滤液蛋白10-早期分泌性抗原靶6(CFP10-ESAT6)真核表达质粒并转染RAW264.7巨噬细胞,观察胞内表达CFP10-ESAT6对细胞活性及凋亡的影响,并初步探讨其机制。方法:将CFP10-ESAT6融合基因插入真核表达质粒pEGFP-N1,构建重组质粒,转染RAW264.7巨噬细胞。采用MTT的方法测定CFP10-ESAT6融合蛋白对RAW264.7巨噬细胞活性的影响,采用结核分枝杆菌19 kD脂蛋白和十字孢碱(staurosporine)处理RAW264.7巨噬细胞,并以流式细胞术检测细胞凋亡率以及Toll样受体2(TLR2)的表达。结果:成功构建了重组质粒pEGFP-N1/CFP10-ESAT6并转染至RAW264.7巨噬细胞;与对照组相比,胞内表达CFP10-ESAT6不能影响巨噬细胞的活性,但可以明显抑制结核分枝杆菌19 kD脂蛋白所造成的凋亡(P<0.05),并显著抑制了TLR2的表达(P<0.05)。结论:巨噬细胞内表达的CFP10-ESAT6融合蛋白不具有细胞毒性作用,但可以通过下调TLR2的表达来抑制结核分枝杆菌19 kD脂蛋白所造成的凋亡。AIM：To establish Mycobacterium tuberculosis culture filtrate protein 10 （CFP10）-early secretory antigenic target 6 （ESAT6） eukaryotic expression vector and investigate the effect of intracellular expression of CFP10-ESAT6 fusion protein on the proliferation and apoptosis of mouse macrophages （RAW264.7 cells）. METHODS：The recombinant plasmid pEGFP-N1/CFP10-ESAT6 was constructed by inserting CFP10-ESAT6 fusion gene into eukaryotic expression vector pEGFP-N1, and then transfected into RAW264.7 cells to express CFP10-ESAT6 fusion protein. The viability of RAW264.7 cells was measured by MTT assay. Flow cytometry was applied to measure the apoptotic rate and Toll-like receptor 2 （TLR2） expression in RAW264.7 cells treated with Mycobacterium tuberculosis 19 kD lipoprotein or staurosporine. RESULTS：The recombinant plasmid pEGFP-N1/CFP10-ESAT6 was successfully constructed and transfected into RAW264.7 cells. Compared with the control cells, intracellular expression of CFP10-ESAT6 fusion protein did not affect the viability of RAW264.7 cells, but could inhibit the apoptosis of RAW264.7 cells treated with Mycobacterium tuberculosis 19 kD lipoprotein. Moreover, CFP10-ESAT6-expressing macrophages had markedly lower expression of TLR2 on the surface. CONCLUSION：Intracellular expression of CFP10-ESAT6 fusion protein has no cytotoxicity on mouse macrophages, but can inhibit the apoptosis of the macrophages treated with Mycobacterium tuberculosis 19 kD lipoprotein through down-regulating the expression of TLR2.

关 键 词：结核分枝杆菌 培养滤液蛋白10 早期分泌性抗原靶6 巨噬细胞 细胞增殖 细胞凋亡 

分 类 号：R363[医药卫生—病理学]