红霉素作用于TLR3/NF-κB通路影响烟草烟雾暴露下树突状细胞活化的研究

In the development of chronic obstructive pulmonary disease (COPD), the accumulation and activation of large numbers of dendritic cells in the lungs were found, cigarette smoke extracts（CSE） can promote dendritic cells to maturation and activation and increase costimulatory molecules expression, erythromycin can regulate function of dendritic cells, the specific mechanism is unknown. In this study, we investigate the TLR3/NF-κB pathway in dendritic cells treated with CSE, on the condition of activating or blocking TLR3/NF-κB pathway. Then we use mice knocked out the TLR3 and NF-κB genes, to observe the effect of CSE on the activation of their dendritic cells, the degree of emphysema and the airway inflammation without TLR3/NF-κB. Finally, we use erythromycin on the CSE pretreating dendritic cells in vitro, and the smoke inducing emphysema mice model in vivo, to study the anti-inflammatory effect of erythromycin in COPD via TLR3 /NF-κB pathway. This study is helpful to explore the mechanism of immune inflammatory of COPD and to find a new effective drug target.

慢性阻塞性肺疾病（COPD）的发展过程中肺部大量树突状细胞聚集、活化，烟草烟雾的刺激可促进树突状细胞成熟活化和共刺激分子的表达，红霉素对树突状细胞功能有一定调控作用，具体机制不明。结合我们前期研究和工作基础，本项目分别激活和阻断在烟草烟雾暴露下树突状细胞的TLR3/NF-κB通路，观察对树突状细胞活化和功能的影响，并采用敲除TLR3、NF-κB基因的肺气肿小鼠模型，研究缺失TLR3、NF-κB对小鼠树突状细胞活化、肺气肿的程度和气道炎症产生的影响，最后研究红霉素对TLR3/NF-κB通路的干预作用，以阐明烟草烟雾暴露诱导肺气肿形成的相关免疫机制，进一步认识COPD的免疫炎症机制及寻找治疗的新靶点。

红霉素可以抑制烟草烟雾暴露下引起的树突状细胞活化，但是具体机制不明。本课题围绕红霉素作用于TLR3/NF-κB通路影响烟草烟雾暴露下树突状细胞活化进行研究。研究结果：1.体外实验：a. 烟草烟雾刺激可促进小鼠骨髓来源的mDC活化（CD40,CD86表达上调），同时促进TLR3、NF-κB及通路上TRAF3表达增多，此外使得细胞上清炎症因子IFN-α、IFN-β、IL-1β的浓度量升高。b.红霉素干预可以抑制烟草烟雾刺激所致的树突状细胞活化，及上述TLR3/NF-κB通路、炎症因子的升高。2.体内实验：a.烟草烟雾暴露后，小鼠脾脏及肺脏内的mDC活化，TLR3、NF-κB及通路上TRAF3表达增多，此外使得血清炎症因子IFN-α、IFN-β、IL-1β的浓度量升高。b.TLR3激动剂poly（I:C）刺激后同样可使上述指标升高。C.予红霉素干预后，不论烟草烟雾暴露小鼠还是TLR3激动剂刺激小鼠体内树突状细胞活化程度、TLR3/NF-κB通路指标表达量及血清炎症因子浓度均被抑制，同时肺气肿改善。本研究阐明红霉素通过树突状细胞TLR3/NF-κB通路调节COPD/肺气肿免疫炎症的发生，为治疗COPD/肺气肿提供新的思路和靶点。