A族链球菌感染小鼠巨噬细胞初期大量诱生SOCS-1蛋白的机制研究  

Study on group A streptococcus induced initial expression of SOCS-1 protein in murine macrophages

作　　者：吴景华[1] 郭佳培 王海欣[2] 李玉华 王志刚 

机构地区：[1]河北联合大学附属医院检验科,河北唐山063000 [2]唐山中医医院口腔科,河北唐山063000 [3]唐山协和医院口腔科,河北唐山063000 [4]唐山丰润区第二人民医院检验科,河北唐山063000

出　　处：《现代预防医学》2015年第16期2993-2996,共4页Modern Preventive Medicine

基　　金：唐山科技局课题(13130211b)

摘　　要：目的本研究利用A族链球菌(GAS)感染小鼠巨噬细胞,来分析SOCS-1的表达情况,以此探索GAS进行免疫逃逸的可能机制。方法同时培养RAW264.7巨噬细胞和C57小鼠骨髓巨噬细胞(BMDMs),以感染复数(MOI)100∶1加入对数生长期GAS及经热灭活处理的GAS(70℃加热处理60 min)刺激RAW264.7及BMDMs巨噬细胞1 h,弃去细菌后,继续培养2,4,6,8,10 h,分别收集细胞,通过RT-PCR及Western blot方法检测JAK/STAT通路的活化及SOCS-1的表达情况。结果 GAS感染RAW264.7及BMDMs细胞4 h后p-STAT1的水平明显高于热灭活组(P<0.05),6 h达到高峰,8 h后开始降低;同时,两组细胞SOCS-1基因的表达,GAS组4 h开始明显升高,6 h达到高峰,8 h开始降低;而热灭活GAS组SOCS-1基因在感染后6 h后开始升高,且升高的幅度明显小于GAS组(P<0.05)。SOCS-1蛋白在GAS感染后6 h可以检测到,而热灭活GAS刺激细胞10h检测不到SOCS-1的表达。结论GAS感染小鼠初期通过快速活化JAK/STAT通路引起SOCS-1的表达,以此来逃避机体的免疫攻击。Objective The aim of this study was to explore the expression of SOCS-1 in GAS-infected murine macrophages for further understanding of GAS strategy in the evasion from macrophages. Methods The RAW264.7 cells and BMDMs cells derived from C57 mice were cultured. GAS in the log phase and inactivated GAS（heated 60 min at 70℃） were used to infect macrophage RAW264.7 and BMDMs（MOI 100： 1）. After one hour, the bacterial was discarded and the treated cells were collected at 2h, 4h, 6h,8h and 10 h. The activation of JAK/STAT and the expressions of SOCS-1 on treated cells were detected by RT-PCR and western blot. Results The levels of p-STAT were significantly higher in GAS infected cells than in nonviable infected cells（P〈0.05）. And it peaked at 6h and decreased in 8h. SOCS-1 m RNA level was elevated at 4h after GAS infection and peaked at 6h. After eight hours,SOCS-1 expression began to decline, whereas peak levels of SOCS-1 m RNA in non-viable GAS-treated cells were delayed（elevated at 6-8h） and were reduced when compared with GAS-induced infection（P〈0.05）. The SOCS-1 protein was detected after six hours in GAS-infected macrophages, but macrophages infected with non-viable GAS did not show any apparent increase in SOCS-1 protein expression within ten hours of stimulation. Conclusion GAS-induced infection induced rapid activation of JAK/STAT signal and expression of SOCS-1 protein in the early infection stage.

关 键 词：GAS 巨噬细胞 JAK/STAT通路 SOCS-1 

分 类 号：R117[医药卫生—公共卫生与预防医学]