THU0077 MIR-155 Facilitate the Differentiation of Th17 Cells by Inhibiting the Gene Expression of Ets-1

Background MiR-155, an essential molecule in normal immune function, which is known to be a central regulator in the immune system, plays an important role in the development and differentiation of Th17 in recent studies. Ets-1 is a significant negative regulative factor of IL-17 generated by Th17 subset. Bioinformatics analysis and experiments as well verify that Ets-1 is also the target gene of miR-155. Objectives To elucidate the function way of miR-155 in the differentiation of Th17 cells. Methods CD4+T cells were separated from mice spleens and cultured with interleukins which can induce CD4+T cells differentiate into Th17 cells. IL-17 was detected by flow cytometry and ELISA after transfected with miR-155 mimics or inhibitor lentviral vectors. The expression levels of miR-155, IL-17A mRNA and Ets-1 mRNA were detected using quantitative reverse transcription PCR (qRT-PCR). The effect of si-Ets and miR-155 co-function for Th17 differentiation was analyzed. Results The CD4+T cells were divided into four groups (control untreat group, control treat group, miR-155 minics group and miR-155 inhibitor group). IL-17 was scarcely expressed and secreted in the control untreat group. IL-17 was expressed and secreted higher in the miR-155 minics group than that in the miR-155 inhibitor group and in the control treat group (P (P (P Conclusions miR-155 can induce CD4+T cells differentiate into Th17 cells by inhibiting the gene expression of Ets-1. Disclosure of Interest None declared