Epstein-Barr virus (EBV) encoded latent membrane protein 1 (LMP-1) triggered inflammatory response through NFκB p65 signaling pathway in tonsils

Tonsils, which exposed continually to antigens, are the important site for recurrent inflammation in the pediatric population. The purpose of this study was to investigate the presence of Epstein-Barr virus (EBV) in children’s tonsils, and to reveal the potential infection mechanism correlation with latent membrane protein 1 (LMP-1) encoded by EBV in human tonsil epithelial cell (HTEpiC). Polymerase chain reaction (PCR) was used to examine the presence of EBV in tonsil tissues which from children aged between 2 and 14 years diagnosed with recurrent tonsillitis. Then the LMP-1 encoded by EBV was overexpressed in HTEpiCs. The mRNA and protein levels of LMP-1 were detected after transfecting for 48 h. Western blot and ELISA were adopted to detect the expression of NF-κB p65, TNF alpha, IL-1 beta and IL-8 in LMP-1 overexpressed HTEpiCs. Of all the 30 patients, PCR products amplified from EBV DNA were detected in the tonsils from the 17 patients (56.67%). And there were no direct relationship between EBV infection and age (P>0.05), gender (P>0.05) or nationality (P>0.05). Overexpression of LMP-1 gene enhanced the expression of inflammatory factors such as TNF alpha, IL-1 beta and IL-8 in HTEpiCs. The level of NF-κB p65 also showed a statistically significant increase in this model. These results suggested that EBV was associated with recurrent tonsils of children. The LMP-1 gene which encoded by EBV could trigger inflammatory response through NF-κB p65 signaling pathway.