NCR-ILC3细胞在小鼠COPD中的作用及机制

Chronic obstructive pulmonary disease (COPD) is cigarette-induced and immune-related inflammatory disease, which leads to airway remodeling and pulmonary damage. Recent study found an increased number of NCR negative innate lymphoid cells 3 (ILC3), a novel innate immunocyte that secrets IL-17, in the pulmonary of COPD patients when compared with controls. Moreover, in our pilot study, we found that the number of NCR-ILC3 in pulmonary was higher in cigarette-induced COPD mice than that in control, which was positively correlated with alveolar destruction. Thus, we suppose that NCR-ILC3 may contribute to COPD/emphysema development. This present study will investigate the relationship between NCR-ILC3 number and pathologic change of lung based on cigarette-induced COPD mice. The primary NCR-ILC3 will be isolated from mice lung and stimulated with cigarette smoke extract (CSE), aiming to study the effect of CSE on NCR-ILC3. We will further isolate primary airway epithelial cells and culture them with the primary NCR-ILC3, and then inhibit the downstream of IL-17 receptor, namely Act1/TRAF6/NF-kB and Act1/TRAF6/p38MAPK signaling by inhibitors, in order to explore the effect of NCR-ILC3 on airway epithelial cells and its potential mechanism in the microenvironment with both cells coexisting. The present study will provide further understanding on mucosal and innate immune responses of lung in COPD, which may contribute to inhibit immune damage of lung.

慢性阻塞性肺疾病（COPD）是香烟诱发持续的免疫炎症导致气道重塑和肺部损伤的疾病。新近研究发现COPD患者肺部分泌IL-17的NCR阴性天然淋巴细胞亚群3（NCR-ILC3）数量增多；我们的预实验发现在香烟诱导COPD小鼠肺部该细胞增多，并与肺气肿程度正相关。由此我们假设NCR-ILC3参与COPD/肺气肿的发生，拟通过香烟诱导COPD小鼠研究NCR-ILC3对COPD肺部病理改变的影响；分离原代NCR-ILC3细胞与香烟提取物共培养，研究香烟对NCR-ILC3的影响；分离原代气道上皮细胞与NCR-ILC3共培养，并阻断上皮细胞内IL-17受体下游的Act1/TRAF6/NF-kB和Act1/TRAF6/p38MAPK通路，探讨在两种细胞共存的微环境下NCR-ILC3对气道上皮细胞的影响及机制。本研究能更深入了解肺部黏膜固有免疫在COPD发生中的作用，有助于阻止COPD肺部免疫损伤的发生。

慢性阻塞性肺疾病（COPD）是香烟诱发持续的免疫炎症导致气道重塑和肺部损伤的疾病。COPD持续的气流受限与气道发生结构性的改变有关。本课题通过香烟诱导建立COPD小鼠模型，检测到COPD小鼠肺部的NCR阴性天然淋巴细胞亚群3（NCR-ILC3）数量增多，并且与肺部病理损伤和支气管上皮间质转变(EMT)有关。分离原代NCR-ILC3细胞与香烟提取物共培养，发现香烟可以刺激NCR-ILC3分泌IL-17的功能。分离原代支气管上皮细胞与NCR-ILC3共培养，并阻断上皮细胞内IL-17受体下游的NF-kB、MAPK信号，发现在两种细胞共存的微环境下，NCR-ILC3可以促进支气管上皮细胞EMT，其机制与NF-kB、MAPK信号活化有关。分离原代支气管上皮细胞与IL-17和/或香烟提取物共培养，并阻断NF-kB、MAPK和C-EBPβ信号，进一步证实NCR-ILC3分泌的IL-17可以通过激活支气管上皮细胞内的NF-kB、MAPK和C-EBPβ信号，促进支气管上皮发生EMT。综上所述，NCR-ILC3细胞在香烟诱导下活化，分泌IL-17通过支气管上皮细胞的IL-17受体，激活上皮细胞内的NF-kB、MAPK和C-EBPβ信号，促使支气管上皮细胞发生EMT。本研究有助于更深入了解肺部黏膜固有免疫在COPD发生中的作用，有助于阻止COPD肺部免疫损伤的发生，有助于针对阻止COPD患者小气道结构发生病态改变，从免疫调节的角度，开发新型的治疗方法。