MicroRNA-181a对日本血吸虫童虫抗原刺激巨噬细胞的免疫应答起负调节作用

MicroRNA-181a plays a negative immune regulation role in macrophages stimulated with soluble schistosomula antigens of Schistosoma japonicum

用日本血吸虫童虫抗原SSA和miR-181a模拟物分别或共同刺激/转染RAW264.7巨噬细胞,再用实时定量PCR技术或流式细胞术分析细胞miR-181a和TNF-α等细胞因子及M1型和M2型巨噬细胞标记分子的表达变化。结果显示,日本血吸虫童虫抗原SSA刺激RAW264.7细胞后,miR-181a及IL-1β、IL-4、TNF-α、IL-10、IL-6等促炎因子上调表达,IL-13下调表达;miR-181a模拟物单独转染RAW264.7巨噬细胞后,细胞因子IL-6、IL-1β、TNF-α和M1型巨噬细胞标记分子INOS等下调表达,IL-4和M2型巨噬细胞标记分子arg-1上调表达。巨噬细胞先用SSA刺激后再转染miR-181a模拟物,IL-1β、IL-4、TNF-α、IL-10、IL-6等促炎因子都下调表达。流式细胞术分析结果显示,miR-181a对M1型标记物CD16/32的表达起到下调作用,对M2型标记分子CD206的表达起上调作用。本研究提示miR-181a对日本血吸虫SSA抗原刺激的巨噬细胞的免疫应答可能起负调节作用,并促进巨噬细胞向M2型细胞转化。

Macrophages RAW264.7 were stimulated and/or transformed with soluble schistosomula antigens（SSA） of Schistosoma japonicum and/or miR-181a mimics. The expression level of miR-181a, TNF-α and other cytokines,as well as M1 and M2 cell marker molecules were analyzed by real-time quantitative PCR or flow cytometry. The results showed that the expression of miR-181α,IL-1β,IL-4, TNF-α,IL-10 and IL-6 was up-regulatedwhen the cells were stimulated with SSA. While IL-6 and IL-β, TNF-α and INOS were down-regulated,IL-4 and arg-1 were up-regulated after RAW264.7 macrophages were transfected with miR-181a mimics alone. And the expression of IL-1β,IL-4,TNF-α,IL-10 and IL-6 was all down-regulated when the macrophages were first stimulated with SSA then transformed with miR-18la mimics. The results of flow cytometry showed that miR-181a mimics could down-regulate the expression of CD16/32,and up-regulate the expression of CD206. This study suggests that miR-181a may play anegative immune regulation role in macrophages stimulated with SSA,and promote the transformation of M1 to M2 macrophages.