Expression and clinical significance of miRNA-146a and IRF-3 in children with infectious mononucleosis

Objective:To investigate the expression levels of interferon regulatory factor 3(IRF-3)and miRNA146a in peripheral blood of children with infectious mononucleosis and the effect of miRNA146a on IRF-3 expression.Methods:In an in vivo experiment,the expression levels of IRF-3 and miRNA146a in peripheral blood of 45 children with infectious mononucleosis and 34 healthy controls were detected by real-time PCR.The in vitro experiment was performed to examine the effect of miRNA146a on IRF-3 expression levels by transfecting miRNA146a mimics and their inhibitors.Results:There was significant difference in IRF-3 gene expression in peripheral blood between healthy controls and children with infectious mononucleosis(t=30.340,P<0.001)while miRNA146a expression was significantly increased compared with healthy controls(t=34.659,P<0.001),and there was a negative correlation between the two groups(r=-0.960,P<0.05).In HeLa cells,transfection with miRNA146a mimics significantly decreased the expression of IRF-3 mRNA(t=8.270,P<0.001)and protein(t=46.170,P<0.001),while miRNA146a inhibitor significantly up-regulated the expression of IRF-3 mRNA(t=8.582,P<0.001)and protein(t=25.891,P<0.001).Conclusion:miRNA146a may be involved in the down-regulation of IRF-3 gene expression by Epstein-Barr virus in children with infectious mononucleosis and then involved in the pathogenesis of infectious mononucleosis.