Abstract:OBJECTIVE: This study examined the expression of Toll-like receptors (TLR) in peripheral blood mononuclear cells (PBMC) and serum levels of IL-6, IL-10 and TNF-α in children with recurrent herpes simplex, in order to investigate the role of TLR2 and TLR9 in recurrent herpes simplex. METHODS: The expression of TLR2 and TLR9 in PBMC was examined by flow cytometer, and serum levels of IL-6, IL-10 and TNF-α were detected using ELISA in 22 children with recurrent herpes simplex and in 13 age-matched healthy volunteers. RESULTS: The expression of both TLR2 and TLR9 obviously increased in children with recurrent herpes simplex compared with that in healthy controls (P<0.01). Serum levels of IL-6 and IL-10 increased, while serum TNF-α levels decreased significantly in children with recurrent herpes simplex compared with those in healthy controls (P<0.01). There were positive correlations between TLR2 and TLR9 expression and serum IL-6 and IL-10 levels in children with recurrent herpes simplex (P<0.01). CONCLUSIONS: TLR2 and TLR9 in PBMC may participate in the recognition of herpes simplex virus and activate the signal pathway of TLR in children with recurrent herpes simplex. The production and release of IL-6 and IL-10 might be mediated by TLR2 and TLR9.[Chin J Contemp Pediatr, 2009, 11 (9):722-724]