IL-27在肺纤维化发病机制中的作用

IL-27 is a member of the IL-6/IL-12 family of cytokines, plays a role in immune regulation, especially in T cell differentiation.But the role and possible mechanism of IL-27 in pulmonary fibrosis have remained unexplored.The project intends to study:① By using the model of bleomycin-induced pulmonary fibrosis ,we clarify the expression,location,cell origin of IL-27 in pulmonary fibrosis;by in vivo injection of IL-27 and IL-27 antibody,the formation of lung fibrosis,T lymphocyte differentiation and secretory function were observed. ② Spleen lymphocytes were co-cultured with IL-27, we confirmed that the role of IL-27 on T lymphocyte differentiation and secretory function. ③ Primary lung fibroblasts ,alveolar type II epithelial cells, NIH/3T3 cell lines, and p3×FLAG-CMV-14/WSX-1cDNA transfected NIH/3T3 cell lines were cultured,the role of IL-27 on the proliferation ,differentiation and secretion of lung fibroblast and the epithelial-mesenchymal transition of the alveolar epithelial cells were observed. ④ We confirmed that IL-27 were involved in the formation of pulmonary fibrosis via the JAK /STAT,TGF-β/Smad signaling pathways in vivo and in vitro. The completion of this project will promote the mechanism of pulmonary fibrosis, and will help to seek the new strategies and targets of drug treatment in the pulmonary fibrosis.

IL-27是IL-6/IL-12家族细胞因子，具有广泛的免疫调节功能。IL-27在肺纤维化形成及其机制尚不清楚。本项目拟研究：① 通过博来霉素诱导肺纤维化模型，阐明IL-27在肺纤维化组织中的表达、定位和细胞来源，通过体内注射IL-27和IL-27抗体，观察对肺纤维化形成、T淋巴细胞分化及分泌功能的影响。② 分离脾淋巴细胞与IL-27共培养，证实IL-27对T淋巴细胞分化及分泌功能的影响。③ 原代培养肺成纤维细胞和肺泡II型上皮细胞，NIH/3T3细胞株，p3×FLAG-CMV-14/WSX-1cDNA转染NIH/3T3细胞株，观察IL-27对肺成纤维细胞增殖、分化、胶原分泌和肺泡上皮细胞转化作用。④在肺组织及细胞上证实IL-27通过JAK/STAT、TGF-β/Smad信号通路参与肺纤维化的形成。本项目的完成可为临床防治肺纤维化提供新的策略和药物干预作用的新靶点。

肺纤维化是一种难治性、高死亡率的肺间质性疾病，早期研究虽然在肺纤维化形成机制取得了许多进展，但是临床治疗面临巨大困难。IL-27是多功能细胞因子，但在肺纤维化形成中的具体机制并不清楚。.本项目通过博来霉素诱导肺纤维化模型及肺纤维化形成中关键的肺泡II型上皮细胞和肺成纤维细胞为主要研究对象，证实如下结论：.1、采用免疫组化和定量PCR的方法检测IL-27参与了肺纤维化的形成，给予IL-27抗体治疗后抑制了肺纤维化形成的程度，降低了小鼠的死亡率。.2、运用流式细胞技术、定量PCR和Western Blot分析IL-27或IL-27抗体与脾淋巴细胞共培养对T淋巴细胞分化和炎症因子分泌，结果证实IL-27抑制了CD4+ IL-17+, CD4+ IL-4+ T和 CD4+ Foxp3+细胞的分化及IL-17, IL-4, IL-6和TGF-ß分泌，促进了CD4+ IL-10+， CD4+ INF- γ+ T细胞的分化。.3、运用MTT法、免疫荧光、定量PCR和Western Blot方法证实IL-27抑制肺成纤维细胞增殖、分化（ɑ-SMA）作用和分泌功能。IL-27抑制TGF-ß诱导肺泡II型上皮细胞向间充质细胞转化。.4、在博来霉素诱导肺纤维化的肺组织、肺成纤维细胞和肺泡II型上皮细胞中证实IL-27调节JAK/STAT和TGF-β/Smad信号通路相关信号蛋白参与了肺纤维化的形成.为此，从体内到体外、细胞到整体多个角度来阐明IL-27在肺纤维化形成中的作用机制，为肺纤维化的防治提供新的理论基础。