Dexamethasone Reduces IL-17 and Tim-3 Expression in BALF of Asthmatic Mice

摘要

This study investigated the expression of interleukin-17 (IL-17) and T cell immunoglobulin mucin and domain-containing molecule-3 (Tim-3) in bronchoalveolar lavage fluid (BALF) of asthmatic mice and the effect of dexamethasone (DEX) on these factors.Thirty-six mice were randomly divided into three groups:normal group,asthmatic group and DEX group.The mouse model of asthma was established by sensitization with ovalbumin in both the asthmatic and DEX groups.The levels of IL-6,IL-10,IL-17 and TGF-β were measured in BALF by enzyme-linked immunesorbent assay (ELISA).The mRNA expression level of Tim-3 was detected by reverse transcription polymerase chain reaction (RT-PCR).The ratio of Tim-3+CD4+ cells to total CD4+ cells in BALF was determined by flow cytometry.Differential inflammatory cells in BALF were detected.The correlations among IL-17,IL-6,IL-10,Tim-3 and inflammatory cells were analyzed.The results showed that the levels of IL-17,IL-6 and Tim-3 were substantially increased and the IL-10 level decreased in BALF in the asthmatic mice,which was significantly reversed by DEX treatment.IL-17 expression was positively correlated with IL-6 and Tim-3 expression and the number of inflammatory cells but negatively with IL-10 expression.These results indicate that the increased expression of IL-17 and Tim-3 in BALF may be implicated in the occurrence and development of asthmatic inflammation;the mechanism by which DEX suppresses asthmatic airway inflammation involves down-regulation of IL-17 and Tim-3 levels.