Kim Hyun Jung, Kim You-Sun, Kim Kang-Hyun, Choi Jun-Pyo, Kim Yoon-Keun, Yun Sunmi, Sharma Lokesh, Dela Cruz Charles S, Lee Jae Seung, Oh Yeon-Mok, Lee Sang-Do, Lee Sei Won
Department of Internal Medicine, Kyungpook National University School of Medicine, Daegu, Republic of Korea.
Department of Pulmonary and Critical Care Medicine, Clinical Research Center for Chronic Obstructive Airway Disease, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
Exp Mol Med. 2017 Apr 14;49(4):e316. doi: 10.1038/emm.2017.7.
Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease, and bacterial infection plays a role in its pathogenesis. Bacteria secrete nanometer-sized extracellular vesicles (EVs), which may induce more immune dysfunction and inflammation than the bacteria themselves. We hypothesized that the microbiome of lung EVs might have distinct characteristics depending on the presence of COPD and smoking status. We analyzed and compared the microbiomes of 13 nonsmokers with normal spirometry, 13 smokers with normal spirometry (healthy smokers) and 13 patients with COPD by using 16S ribosomal RNA gene sequencing of surgical lung tissue and lung EVs. Subjects were matched for age and sex in all groups and for smoking levels in the COPD and healthy smoker groups. Each group included 12 men and 1 woman with the same mean age of 65.5 years. In all groups, EVs consistently showed more operational taxonomic units (OTUs) than lung tissue. In the healthy smoker and COPD groups, EVs had a higher Shannon index and a lower Simpson index than lung tissue and this trend was more prominent in the COPD group. Principal component analysis (PCA) showed clusters based on sample type rather than participants' clinical characteristics. Stenotrophomonas, Propionibacterium and Alicyclobacillus were the most commonly found genera. Firmicutes were highly present in the EVs of the COPD group compared with other samples or groups. Our analysis of the lung microbiome revealed that the bacterial communities present in the EVs and in the COPD group possessed distinct characteristics with differences in the OTUs, diversity indexes and PCA clustering.
慢性阻塞性肺疾病（COPD）是一种慢性炎症性疾病，细菌感染在其发病机制中起作用。细菌分泌纳米级的细胞外囊泡（EVs），其可能比细菌本身诱导更多的免疫功能障碍和炎症。我们假设，根据COPD的存在和吸烟状态，肺EVs的微生物群可能具有不同的特征。我们通过对手术肺组织和肺EVs进行16S核糖体RNA基因测序，分析并比较了13名肺功能正常的非吸烟者、13名肺功能正常的吸烟者（健康吸烟者）和13名COPD患者的微生物群。所有组的受试者在年龄和性别上进行了匹配，COPD组和健康吸烟者组在吸烟水平上进行了匹配。每组包括12名男性和1名女性，平均年龄均为65.5岁。在所有组中，EVs始终显示出比肺组织更多的可操作分类单元（OTUs）。在健康吸烟者和COPD组中，EVs的香农指数较高，辛普森指数较低，且这种趋势在COPD组中更为明显。主成分分析（PCA）显示聚类是基于样本类型而非参与者的临床特征。嗜麦芽窄食单胞菌、丙酸杆菌和 Alicyclobacillus是最常见的属。与其他样本或组相比，COPD组的EVs中厚壁菌门含量很高。我们对肺微生物群的分析表明，EVs和COPD组中存在的细菌群落具有不同的特征，在OTUs、多样性指数和PCA聚类方面存在差异。
