IL-17A is involved in spleen damage during acute murine disseminated MCMV infection / 中华微生物学和免疫学杂志

ABSTRACT

Objective To explore the correlation between the expression of IL-17A and the degree of spleen damage in acute mouse cytomegalovirus(MCMV) disseminated infection in vivo and to understand the mechanism about how IL-17A involved in the pathological damage of the spleen in MCMV infection.Methods An acute disseminated MCMV infection model was established in mice.BALB/c mice were randomly divided into two groups.Mice in group one were infected with MCMV Smith to establish disseminated infection.Mice in another group were sham-infected control.Three mice from each group were randomly chosen to be sacrificed on days 3,7,14 and 28 after the infection.Viral titers in spleen tissues were determined using a standard plaque assay.The expression of IL-17A mRNA and MCMV mRNA in the splenocytes were measured by RT-PCR.The expression of IL-17A in spleen tissues was observed by immunohistochemical staining.The pathology of the infected mice was assessed by histological examination of H&E stained spleen sections.Results Viral titers and MCMV mRNA in the spleen peaked on day 3,but quickly diminished on day 7.Virus was no longer detectable in the spleen on day 14 after the infection.The expression of IL-17A mRNA was significantly increased during the acute infection and reached the highest level on day 14,then decreased on day 28.It is significantly higher than that of the mock infection group.Immunohistochemistry assay also indicated that the expression of IL-17A in spleen tissue gradually increased to climax on day 14,then decreased on day 28.Accordingly,the pathological damages of spleen tissue in the infected mice deteriorated until day 14,then showed signs of recovery on day 28.The most severe pathological injury of spleen tissue and the highest expression of IL-17A appeared in the same period of time.Conclusion Our results showed a close correlation between IL-17A and the pathological damage in spleen.Thus,IL-17A may contribute to the spleen pathological damage during the acute disseminated MCMV infection.