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Objective:By comparing the expression levels of retinoic acid-related orphan nuclear receptorγt( RORγt) and in-terleukin-17 ( IL-17 ) in newborn rats′spleen tissue with cytomegalovirus infection with normal newborn to provide experimental evidence for the pathogenesis of CMV infection.Methods:Forty-eight newborn BALB/c mice were randomly divided into control group and MCMV group.Mice in virus group was given intraperitoneal injection of MCMV virus suspension,while the control group were given the same dose of normal saline as controls.Eight mice in the two groups were killed at day 3,7 and 14.The animal were sacrificed at day 3,7 and 14( n=8 for each interval) and spleens were obtained from the two groups.MCMV DNA,RORγt mRNA,IL-17 mRNA and protein of RORγwere detected by using RT-PCR and Western blot between the two groups.Results:Expression of MCMV DNA was in-creased in the MCMV group but absent in the control group.RORγt mRNA, IL-17 mRNA and protein expression of RORγt were significantly higher than the normal control group,with the extension of the infection time gradually increased( P<0.05 ) .Conclusion:The IL-17 and RORγt in spleen tissue may take part in the inflammatory response induced by MCMV, and may be involved in the pathogeneses of MCMV injury.
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ObjectiveTo observe the changes of AIM2 ( absent in melanoma 2) inflammasome during early murine cytomegalovirus (MCMV) infection.MethodsBALB/c mice were randomly divided into two groups.One was infected with MCMV Smith for establishing disseminated infection,the other was sham-inoculated control.On days 1,3,5 and 7 of the experiment,three mice of each group were randomly chosen to be killed separately.The expression of AIM2,ASC and caspase-1 in splenic macrophages was detected by Western blot,the levels of IL-1β and IL-18 in sera were measured by double antibody sandwich ELISA,and the viral titers in salivary gland tissues were quantified by a standard plaque assay.Results The MCMV titers in salivary gland tissues were gradually increased in MCMV-infected mice on days 3,5 and 7,while the expressions of AIM2 in macrophages were began to increase on day 1 and significantly increased and reached the highest level on day 3 but gradually decreased afterwards.The relative intensity of AIM2 on day 3 differed significantly between the MCMV-infected mice and the controls (1.121±0.243 vs 0.240±0.046,P＜0.01,t test),as did ASC ( 1.318±0.333 vs 0.248±0.090,P＜0.01 ) and caspase-1 ( 1.085±0.243 vs 0.247±0.064,P＜0.01 ).Meanwhile,the levels of IL-1β and IL-18 in MCMV-infected mice were (112.72±5.20) pg/ml and (42.74±4.23) pg/ml,and the levels were significantly higher (P＜0.01 ) than those in controls [ (47.86±4.35) pg/ml and (22.60±2.82) pg/ml].ConclusionThese results demonstrate that AIM2 inflammasome is activated in macrophages during early MCMV infection and could be as a therapeutic target for CMV-induced diseases.
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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 supernatants of splenocytes 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 frequencies 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 dramatically 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 MCMV-specific IL-17A in culture supernatants and MCMV loads in salivary gland tissues (r=0.54,P＜0.05 ),the levels of IL-17 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 correlate with the persistence of MCMV and the pathology of spleen in infected mice.
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Summary: In order to study the expression of IL-1β and TNF-α in the myocardium of MCMV myocarditis and their role in the myocardial damages, 60 BALB/C mice of 4 weeks were randomly divided into two groups: 36 were injected intraperitoneally with MCMV and 24 served as control group. Immunohistochemistry was used to detect IL-1β and TNF-α expression in the myocardium, and myocardial lesions were observed histopathologically. Histopathological study on the myocardium from infected mice revealed focal or diffuse lesions characterized by inflammatory cells and degeneration or necrosis of myocytes. The myocardial lesion score showed the degree of inflammatory cell infiltration was slight in MCMV myocarditis.The positive staining signals for IL-1β and TNF-α proteins which mainly located in the infiltrating inflammatory cells and degenerative or necrotic myocytes were markedly detectable whereas there were no positive findings in the myocardium of control mice. IL-1β and TNF-α was expressed in the myocardium of viral myocarditis murine model induced by MCMV. IL-1β and TNF-α may play an important role in the pathogenesis of viral myocarditis.