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目的:利用生物信息学方法挖掘呼吸机相关性肺损伤（VILI）小鼠的差异表达基因（DEG），并通过构建VILI小鼠模型对关键基因进行验证。方法:①实验1（生物信息学分析）：从基因表达数据库（GEO）下载VILI与自主呼吸对照组小鼠的肺组织基因芯片数据GSE9368和GSE11662，通过统计分析获得DEG，运用韦恩图获得两个数据的共同DEG，然后使用DAVID在线数据库对共同DEG进行基因本体（GO）功能注释和京都基因与基因组百科（KEGG）通路富集分析，最后利用基因与蛋白质相互作用检索在线数据库（STRING）对共同DEG进行基因编码蛋白相互作用（PPI）分析，并运用CytoScape软件、分子复合物检测分析插件（MCODE），以及CytoHubba插件中最大团中心性（MCC）、最大邻居连通度（MNC）与度（degree）算法进行拓扑分析，筛选出关键基因。②实验2（相关基因编码蛋白验证）：构建C57BL/6小鼠大潮气量（20 mL/kg）VILI模型，并设自主呼吸对照组。取小鼠肺组织进行苏木素-伊红（HE）染色，观察肺组织病理学改变；并对实验1中筛选出的关键基因编码蛋白进行免疫组化验证。结果:①实验1结果：GSE9368数据中筛选出114个DEG，其中上调99个，下调15个；GSE11662数据中筛选出258个DEG，其中上调188个，下调70个；获得共同DEG 66个，其中上调61个，下调5个。GO功能注释结果表明，共同DEG参与炎症反应、免疫应答、白细胞及中性粒细胞趋化浸润等过程；KEGG通路富集分析提示共同DEG主要富集于细胞黏附、细胞因子-细胞因子受体相互作用及肿瘤坏死因子（TNF）信号通路等。通过STRING及CytoScape构建差异基因PPI网络图和重要子模块，并获得拓扑分析MCC、MNC及degree算法得出的交集基因，分别为细胞因子信号转导抑制因子3（SOCS3）、白细胞介素-1β（IL-1β）、基质金属蛋白酶-9（MMP-9）、整合素Itgam、CXC型趋化因子配体2（CXCL2）、CXC型趋化因子受体2（CXCR2）、L-选择素Sell及CC型趋化因子受体1（CCR1）。②实验2结果：构建大潮气量VILI小鼠模型结果显示，与自主呼吸对照组相比，机械通气结束后0 h小鼠肺组织有所损伤；通气结束后6 h肺组织结构受损明显，肺泡腔可见不同程度出血和塌陷，肺泡壁明显增厚，肺泡腔及间质还可见炎症细胞浸润。对拓扑分析交集前3位基因IL-1β、SOCS3、MMP-9的编码蛋白进行免疫组化染色，结果显示，随通气时间延长，小鼠肺组织中IL-1β、SOCS3、MMP-9蛋白表达逐渐上调，6 h时与自主呼吸对照组比较差异均有统计学意义〔IL-1β（积分n A值）：8.40±2.67比5.10±0.94，SOCS3（积分n A值）：9.74±1.80比5.95±1.31，MMP-9（积分n A值）：11.45±6.20比5.36±1.28，均n P<0.05〕。n 结论:基于GSE9368和GSE11662数据的生物信息学分析发现，VILI与炎症损伤、细胞因子及免疫细胞浸润相关；IL-1β、SOCS3、MMP-9蛋白可能为VILI生物标志物。“,”Objective:To investigate differential expression gene (DEG) in mice with ventilator-induced lung injury (VILI) by bioinformatics analysis, and to verify the key genes by reproducing the VILI mouse model.Methods:① Experiment 1 (bioinformatics analysis): the microarray dataset of GSE9368 and GSE11662 regarding VILI mice and those in the spontaneous breathing control group were downloaded from the gene expression omnibus (GEO) database. DEG obtained by R and Venn map was further used to obtain common DEG. DAVID online database was used to obtain gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Finally, the protein-protein interaction (PPI) analysis of common DEG was carried out by using Search Tool for the Retrieval of Interacting Genes Database (STRING) and the key genes were screened out by using CytoScape software, molecular complex detection (MCODE) analysis plug-in and CytoHubba plug-in with maximum cluster centrality (MCC), maximum neighbor connectivity (MNC) and degree. ② Experiment 2 (related protein verification): VILI mouse model was reproduced by high tidal volume (20 mL/kg) ventilator. Spontaneous breathing control group was set up. Hematoxylin-eosin (HE) staining was performed to assess lung injury and the key genes screened in experiment 1 were verified by immunohistochemical staining.Results:① Experiment 1 results: a total of 114 DEG were screened from GSE9368 dataset, including 99 up-regulated genes and 15 down-regulated genes. A total of 258 DEG were screened from GSE11662 dataset, including 188 up-regulated genes and 70 down-regulated genes. Furthermore, 66 common DEG were obtained, including 61 up-regulated genes and 5 down-regulated genes. GO analysis showed that the common DEG were mainly involved in inflammatory response, immune response, leukocyte and neutrophil chemotaxis. KEGG analysis showed that the common DEG were involved cell adhesion, cytokine receptor interaction and tumor necrosis factor (TNF) signaling pathway. STRING and CytoScape analysis were used to construct gene PPI network diagram and important sub modules. And the CytoHubba plug-in with MCC, MNC and degree algorithms was used to perform topology analysis and then taken an intersection to obtain eight genes including suppressor of cytokine signaling 3 (SOCS3), interleukin-1β (IL-1β), matrix metalloproteinase-9 (MMP-9), integrin Itgam, CXC chemokine ligand 2 (CXCL2), CXC chemokine receptor 2 (CXCR2), Sell and CC chemokine receptor 1 (CCR1). ② Experiment 2 results: a mouse model of high tidal volume VILI was reproduced. Compared with the spontaneous breathing control group, the lung tissue was injured slightly at 0 hour after the end of ventilation, and the lung tissue structure was significantly damaged at 6 hours after the end of ventilation, showing bleeding in alveolar cavity, significant increase and collapse of alveolar wall thickness, and infiltration of inflammatory cells. The top three genes from intersection and topological analysis including IL-1β, SOCS3 and MMP-9 were verified by immunohistochemical staining. The results showed that the expressions of IL-1β, SOCS3 and MMP-9 were gradually increased with time of ventilation, the differences were found at 6 hours as compared with those in the spontaneous breathing control group [IL-1β (integraln A value): 8.40±2.67 vs. 5.10±0.94, SOCS3 (integral n A value): 9.74±1.80 vs. 5.95±1.31, MMP-9 (integral n A value): 11.45±6.20 vs. 5.36±1.28, all n P < 0.05].n Conclusion:Bioinformatics analysis based on GSE9368 and GSE11662 data sets found that VILI is mainly related to inflammatory injury, cytokines and immune cell infiltration; IL-1β, SOCS3 and MMP-9 might be biomarkers of VILI.