多房棘球绦虫分泌的emu-miR-10对中间宿主免疫应答调控的研究

Alveolar echinococcosis (AE) is caused by Echinococcus multilocularis metacestodes in the liver of humans, posing a great threat to human safety and health. An Emu-miR-10 secreted by E. multilocularis were indentified from the E. multilocularis-infected mouse sera, but the biological functions of emu-miR-10 remain unclear. In this study, the relative abundance of emu-miR-10 in immune cells will be observed by using intravital imaging and qPCR, and the effect of emu-miR-10 mimics on the levels of cytokines and NO, cell polarization, apoptosis, as well as the activities of destruction will be detected in host immune cells. This results will be revealed whether the emu-miR-10 has an immunomodulatory effect. The target genes of emu-miR-10 in Toll-like receptor signaling pathway will be screened and the intercation between emu-miR-10 and the target genes will be verified. The effect of emu-miR-10 on the proteins in Toll-like receptor signaling pathway, regulated by the target genes, will be analyzed. These results could elucidate the molecular mechnism of E. multilocularis may secreted own miRNAs into host immune cells by exosomes, thus regulating host immune response by ‘miRNA-target gene-protein’ regulatory network, and enrich the knowledge of interaction between pathogen and host. It has implications in providing experimental proof for development of novel anti-tapeworm approaches.

多房棘球绦虫可寄生于人的肝脏引起泡球蚴病，对人类安全、健康造成巨大威胁。多房棘球绦虫能将emu-miR-10分泌到小鼠血液中，但emu-miR-10的生物学功能目前还不清楚。本项目拟通过活体成像、qPCR等方法检测注射了多房棘球绦虫外泌体小鼠免疫细胞中emu-miR-10的相对丰度；并利用miRNA模拟物检测emu-miR-10对宿主免疫细胞分泌细胞因子、释放NO、及其极化、凋亡、杀伤等活性的影响，探究其对宿主免疫细胞的调节作用；筛选和验证emu-miR-10的靶基因并分析转染其模拟物对受靶蛋白调节的Toll样受体信号通路中关键蛋白的含量、定位及活性的变化情况。此研究将揭示多房棘球绦虫能通过外泌体将其携带的miRNAs运送到宿主免疫细胞中，并通过‘miRNA-靶基因-蛋白’的调控网络调节宿主免疫应答、拓展了对病原与宿主相互作用的认识，对于开发棘球病的新型防治手段提供实验依据。

多房棘球绦虫可寄生于人的肝脏引起泡球蚴病，对人类安全、健康造成巨大威胁。多房棘球绦虫能将emu-miR-10分泌到小鼠血液中，血清中emu-miR-10主要富集在外泌体中。多房棘球绦虫分泌性miR-10能明显促进小鼠巨噬细胞IL-10的表达，却抑制IL-12b的表达。进一步研究发现分泌性miR-10通过抑制干扰素调节因子5来影响小鼠巨噬细胞分泌IL-10和IL-12b，进而调节宿主免疫应答。这些研究结果表明棘球蚴分泌的miRNA在寄生虫逃避宿主免疫应答中发挥一定的作用，为创制新型棘球蚴病防治手段提供重要的实验依据。