Th17细胞在小鼠巨细胞病毒感染急性期的作用研究  

The role of Th17 cells in murine cytomegalovirus infection during the acute stage

作　　者：李旭芳[1] 刘玲玲[1] 刘兴楼[1] 舒赛男[1] 李革[1] 方峰[1] 

机构地区：[1]华中科技大学同济医学院附属同济医院儿科,武汉430030

出　　处：《中华微生物学和免疫学杂志》2012年第2期178-182,共5页Chinese Journal of Microbiology and Immunology

基　　金：基金项目：教育部博士点基金资助项目（20090142110076）

摘　　要：目的整体水平观察Th17细胞在小鼠巨细胞病毒（MCMV）播散性感染急性期的作用。方法建立MCMV播散性感染模型，病毒接种后第3、7、14和28天各处死3只小鼠；同时设模拟感染鼠作为对照。应用real—timePCR法检测MCMV感染鼠脏器MCMVDNA载量；HE染色观察MCMV感染后脾组织病理损伤变化；流式细胞术检测脾细胞中CD4＋IL-17A＋T细胞比率；ELISA法检测脾细胞培养上清中IL-17A蛋白浓度。结果感染急性期唾液腺组织中MCMVDNA于感染后14d最高；脾组织病理损伤也于感染后14d最严重；与模拟感染对照鼠相比，MCMV感染鼠脾细胞中CD4＋IL-17A＋T细胞比率呈升高趋势（均P〈0．01），且于感染后14d达峰值[（1．14±0．09）％VS（0．19±0．04）％，t=17．551，P=0．000]；病毒特异性IL-17A浓度也于感染后14d达峰值[（81．98±12．37）pg／mlVS（44．96±8．44）pg／ml，t=4．281，P=0．006]；脾细胞培养上清中病毒特异性IL-17A水平与唾液腺组织中MCMVDNA载量呈正相关（r=0．54，P〈0．05）；脾组织病理损伤越重，脾细胞培养上清中IL-17A浓度越高。结论Th17细胞主要通过IL-17A参与MCMV播散性感染急性期免疫应答，直接或间接的促进病毒复制或脾组织局部病理损伤，可能是MCMV持续性感染的重要原因之一。Objective To investigate the nature of Th17 cells in murine cytomegalovirus（MCMV） infection during the acute stage, we characterized the frequency of IL-17A-producing CD4 T cells and the level of Th17 cytokines, IL-17A, in MCMV-infected mice. Methods BALB/c mice were randomly divided into two groups. One was infected with MCMV Smith for establishing disseminative infection; the other was sham-inoculated control. On day 3, 7, 14 and 28 of the experiment, three mice of each group were randomly chosen to be killed separately. Real-time PCR was used to detect MCMV loads in organs of MCMV-infected mice, the pathology of spleen was observed by HE staining. The frequency of CD4＋IL-17A＋ T cells in total splenocytes of mice was detected by flow cytometry. The level of IL-17A in culture supematants of spleno- cytes was measured by double antibody sandwich ELISA. Results MCMV loads in salivary gland reached the peak on day 14 after MCMV infection, the most severe spleen injury was also shown on day 14, the fre- quencies of CD4＋IL-17A~ T cells in total splenocytes increased significantly（ all P〈0.01 ） in MCMV-infected mice than those in controls, and reached the peak on day 14 （ 1.14% ±0.09% vs 0. 19% ±0.04%, t = 17. 551, P=0.000）. The levels of MCMV-specific IL-17A in culture supernatants were increased dramatic- ally in MCMV-infected mice than those in controls on day 14 [ （81.98±12.37） pg/ml vs （44.96±8.44） pg/ml, t = 4. 281, P= 0.006 ]. In MCMV-infected mice, correlation was positive between the levels of M C- MV-specific IL-17A in culture supernatants and MCMV loads in salivary gland tissues （r = 0. 54, P〈 0. 0 5 ） , the levels of IL - 1 7 A in culture supernatants were higher in more severe spleen injury. Conclusion Thl7 cells and IL-17A were involved in the immunity response during acute MCMV infection. They may cor- relate with the persistence of MCMV and the pathology of spleen in infected mice.

关 键 词：小鼠巨细胞病毒 TH17细胞 IL-17A 

分 类 号：R[医药卫生]