以线粒体转移为作用机制的iPSC-MSC对呼吸道变应性炎症上皮细胞的作用探讨

The airway epithelium is considered an essential activator and controller of allergic rhinitis (AR) and asthma. Mitochondrial dysfunction plays an important role in the activity of epithelial cells. However, there is no effective treatment to AR and asthma via improving the function of epithelial cells and mitochondria. Bone marrow derived mesenchymal stem cells (MSC) protect against acute lung injury by mitochondrial transfer to injured epithelial cells through Cx43-dependent gap junctional channels. We have reported that induced pluripotent stem cell (iPSC)-derived MSC prevents allergic airway inflammation in mice. However, the mechanism is unclear. Using coculture model of iPSC-MSC and epithelial cell line (16HBE), we observed formation of tunneling nanotubes (TNTs) between MSC and epithelial cell, and there was exchange of mitochondria between two types of cells via TNTs. We next hypothesize that (1) iPSC-MSC has the potential to protect epithelial cells and mitochondria in AR and asthma; (2) iPSC-MSC protects epithelial cells via mitochondrial transfer; (3) Cx43 transfection to iPSC-MSC improves the above effects of iPSC-MSC and has better effects on allergic inflammation of AR and asthma. In this project, we induce a coculture model of iPSC-MSC and epithelial cell from normal cell lines, AR patients, asthma patients and healthy volunteers, and a mice model of AR and asthma. We aim to investigate the protection of iPSC-MSC on epithelial cells and mitochondrial in allergic disease; to investigate whether iPSC-MSC protects epithelial cells via mitochondrial transfer; to examine whether Cx-43-transfected iPSC-MSC improves the above effects and further prevents allergic inflammation. The project will provide a new therapy to AR and asthma. The scientist who first reported iPS won the Nobel Prize in Physiology or Medicine in 2012. This study is timely and may provide useful information to the mechanism of immunomodulation of iPSC-MSC on airway allergic diseases.

上皮细胞是变应性鼻炎（AR）和哮喘的启动及调控者，而线粒体异常是其产生致病作用的关键环节，目前尚无针对此靶点的有效干预措施。在肺损伤模型中，间充质干细胞（MSC）可通过Cx43蛋白形成的连接通道向上皮细胞转移线粒体而发挥疗效。我们报道了诱导性多能干细胞（iPSC）来源的MSC可抑制AR及哮喘炎症但机制尚不清楚。我们前期发现iPSC-MSC与正常上皮细胞间可形成连接通道并存在线粒体的交流，那其是否通过向受损上皮细胞提供新鲜线粒体而防治变应性炎症且能否因上调Cx43蛋白的表达而强化呢？本课题拟通过细胞共培养及小鼠AR及哮喘模型系统探讨iPSC-MSC对上皮细胞、线粒体的作用，是否通过线粒体转移而恢复上皮细胞功能及转染Cx43能否增强上述作用及更强地抑制炎症。iPS是个突破性的科学发现，iPSC-MSC具有强大的应用优势，本研究有助阐明其调节变应性炎症的机制，也为其向临床应用的转化提供理论依据。

项目背景：呼吸道变应性炎症是全球公共健康问题, 其患病率居高不下。呼吸道上皮细胞是变应性鼻炎（AR）和哮喘的启动及调控者，而线粒体异常是其产生致病作用的关键环节，目前尚无针对此靶点的有效干预措施。我们前期报道了诱导性多能干细胞（iPSC）来源的MSC可抑制小鼠AR及哮喘炎症，且发现iPSC-MSC与上皮细胞间可形成连接通道并存在线粒体的交流，但其是否通过向受损上皮细胞提供新鲜线粒体而防治变应性炎症，而细胞间连接蛋白Cx43在其中的作用还不清楚。.主要研究内容：.1）.iPSC-MSC细胞建立及其功能验证、免疫学属性研究；.2）.iPSC-MSC对呼吸道变应性炎症及上皮细胞的作用探讨；.2）线粒体转移在其中的作用；.3）CX43在呼吸道变应性炎症发病过程中的作用。..重要结果：.1）.建立了稳定的iPSC-MSC细胞的诱导分化鉴定平台，并证明其较骨髓来源MSC具有更低的免疫原性，且增殖能力更强、寿命更长等；.2）.证明了iPSC-MSC可与上皮细胞形成缝隙连接并可通过转移线粒体保护上皮细胞；.3）.证明了MSC可通过miRNA-21/ACVR2A、lncRNA信号轴防治呼吸道变应性炎症及呼吸道上皮细胞损伤；..科学意义：. 本项目的实施阐明了iPSC-MSC可通过线粒体转移、调节非编码RNA表达防治呼吸道变应性炎症及呼吸道上皮细胞损伤，为呼吸道变应性炎症的防治提供了新的治疗方案和研究基础。