lncRNA调控免疫代谢在牛结核分枝杆菌诱导肺泡巨噬细胞自噬中的作用机制研究

Pulmonary tuberculosis of bovine is a chronic fatal zoonotic infectious disease caused by an infection of Mycobacterium bovine (M. bovine，Mb), which has significantly hampered a normal and stable development of animal production industry, as well as negatively impacted on the safety of products of milk and meats, and public health. Alveolar macrophages are main targets and immun effectors for Mb infections. Immunometablism and autophagy of Mb-infected alveolar macrophages has a significant impacts on the immune responses of immune cells and immune evasion of intracellular bacteria in macrophages, in which long non-coding RNAs are one of the most important regulatory mechanisms. In the present proposal, we aim to elucidate the underlying molecular mechanism of immunometabolisms of immune responses and autophagy of bovine alveolar macrophages inesponse to M. bovis infections by accomplishing following five special aims, using an alveolar epithelium/macrophage co-culture infection model, in which alveolar epithelia will be cultured under an air-liquid interface state: 1) transcriptome analysis of bovine alveolar macrophages infected with M. bovis using RNA-Seq technology; 2) evaluating the impact of glucose metabolism of bovine alveolar macrophages in immune responses and autophagy aginst M. bovis infection; 3) interrogating roles of lncRNAs of bovine alveolar macrophages in the immunomebolism and autophagy of host cells in response to Mb infections. An accomplishment of this proposal will lay a foundation for understanding the immunometabolism of macrophages induced by Mb infections, and provide a novel strategy for preventing bovine tubuculosis by target ing host metabolism pathways.

牛结核病是由牛结核分枝杆菌(Mb)引起的严重影响畜牧业健康发展和公共卫生安全的一种慢性致死性人兽共患传染病。肺脏巨噬细胞(AM)是Mb感染的主要靶细胞和免疫效应细胞，研究发现，免疫代谢和细胞自噬在AM抗Mb感染和阻止胞内菌逃避宿主细胞免疫监视中发挥重要作用，而长片段非编码RNA(lncRNA) 是调控细胞代谢和自噬的主要模式之一，但其参与调控的机制尚一无所知。本项目拟采用牛肺泡上皮细胞/AM气液相共培养感染模型，通过实施①利用RNA-Seq技术分析牛AM感染Mb过程中转录组的动态变化; ②研究细胞糖代谢对牛AM抗Mb感染免疫反应及细胞自噬的调控机制；③探讨代谢相关lncRNA在AM抗Mb感染中细胞自噬的调控作用机制等研究内容，以期阐明lncRNA调控免疫代谢在Mb感染牛AM过程中细胞自噬的分子调控机制，对进一步揭示Mb的免疫逃逸机制和基于代谢途径的牛结核病免疫机制相关研究具有重要意义。

牛结核病是由牛结核分枝杆菌（Mb）引起的严重影响畜牧业健康发展和公共卫生安全的一种慢性致死性人兽共患传染病。免疫代谢和自噬在肺泡巨噬细胞抗Mb感染和阻止胞内菌逃避宿主细胞免疫监视中发挥重要作用。因此，本项目在建立牛肺泡上皮细胞/巨噬细胞气液相共培养感染模型的基础上，利用RNA-Seq转录组分析技术，剖析lncRNA调控免疫代谢在牛结核分枝杆菌感染牛肺泡巨噬细胞过程中细胞自噬的分子调控机制，对进一步揭示牛结核分枝杆菌的免疫逃逸机制和基于代谢途径的牛结核病免疫机制相关研究具有重要意义。通过项目实施，在分离和培养牛原代肺泡上皮细胞和巨噬细胞的基础上，成功建立了气液相共培养感染模型。完成了牛结核分枝杆菌感染共培养模型及RNA-Seq和lncRNA转录组学差异分析。筛选出功能基因lncRNA SIGLEC6并完成表达谱功能富集，揭示了牛结核分枝杆菌介导lncRNA SIGLEC6调控巨噬细胞炎性反应的分子机制；探索了游离糖通过调控细胞内葡萄糖转运抑制牛结核分枝杆菌感染后宿主细胞自噬发生的现象，揭示了牛结核分枝杆菌介导糖代谢诱发自噬逃避宿主细胞免疫监视的分子机制；进一步发现胆钙化醇类（维生素D3）通过促进自噬和Ca2+释放抑制牛结核分枝杆菌引起小鼠糖代谢紊乱导致肺损伤的分子机制。以上研究，为进一步揭示Mb的免疫逃逸机制和基于代谢途径的牛结核病免疫机制相关研究具有重要意义。