title: Severity-related changes of bronchial microbiome in chronic obstructive pulmonary disease.
abstract: Bronchial colonization by potentially pathogenic microorganisms (PPMs) is often demonstrated in chronic obstructive pulmonary disease (COPD), but culture-based techniques identify only a portion of the bacteria in mucosal surfaces. The aim of the study was to determine changes in the bronchial microbiome of COPD associated with the severity of the disease. The bronchial microbiome of COPD patients was analyzed by 16S rRNA gene amplification and pyrosequencing in sputum samples obtained during stable disease. Seventeen COPD patients were studied (forced expiratory volume in the first second expressed as a percentage of the forced vital capacity [FEV1%] median, 35.0%; interquartile range [IQR], 31.5 to 52.0), providing a mean of 4,493 (standard deviation [SD], 2,598) sequences corresponding to 47 operational taxonomic units (OTUs) (SD, 17) at a 97% identity level. Patients were dichotomized according to their lung function as moderate to severe when their FEV1% values were over the median and as advanced when FEV1% values were lower. The most prevalent phyla in sputum were Proteobacteria (44%) and Firmicutes (16%), followed by Actinobacteria (13%). A greater microbial diversity was found in patients with moderate-to-severe disease, and alpha diversity showed a statistically significant decrease in patients with advanced disease when assessed by Shannon (ρ = 0.528; P = 0.029, Spearman correlation coefficient) and Chao1 (ρ = 0.53; P = 0.028, Spearman correlation coefficient) alpha-diversity indexes. The higher severity that characterizes advanced COPD is paralleled by a decrease in the diversity of the bronchial microbiome, with a loss of part of the resident flora that is replaced by a more restricted microbiota that includes PPMs.
authors.affiliation: Fundació Parc Taulí, Sabadell/Badalona, Spain CIBER de Enfermedades Respiratorias (CIBERES), Bunyola, Spain Universitat Autonoma de Barcelona, Esfera (UAB), Barcelona, Spain Fundació Institut d'Investigació Germans Trias i Pujol, Badalona, Spain mgarcianu@tauli.cat.
authors.forename: Marian
authors.initials: M
authors.lastname: Garcia-Nuñez
authors.affiliation: Fundació Parc Taulí, Sabadell/Badalona, Spain CIBER de Enfermedades Respiratorias (CIBERES), Bunyola, Spain Universitat Autonoma de Barcelona, Esfera (UAB), Barcelona, Spain Fundació Institut d'Investigació Germans Trias i Pujol, Badalona, Spain.
authors.forename: Laura
authors.initials: L
authors.lastname: Millares
authors.affiliation: Universitat Autonoma de Barcelona, Esfera (UAB), Barcelona, Spain Department of Respiratory Medicine, Hospital Universitari Parc Taulí, Sabadell, Spain.
authors.forename: Xavier
authors.initials: X
authors.lastname: Pomares
authors.affiliation: Genomics and Health Area, Centro Superior de Investigación en Salud Pública- Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunidad Valenciana (CSISP-FISABIO), Valencia, Spain CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain Department of Genetics, Institut Cavanilles de Biodiversitat i Biologia Evolutiva (ICBiBE), Universitat de València, Valencia, Spain.
authors.forename: Rafaela
authors.initials: R
authors.lastname: Ferrari
authors.affiliation: Genomics and Health Area, Centro Superior de Investigación en Salud Pública- Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunidad Valenciana (CSISP-FISABIO), Valencia, Spain CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain Department of Genetics, Institut Cavanilles de Biodiversitat i Biologia Evolutiva (ICBiBE), Universitat de València, Valencia, Spain.
authors.forename: Vicente
authors.initials: V
authors.lastname: Pérez-Brocal
authors.affiliation: Universitat Autonoma de Barcelona, Esfera (UAB), Barcelona, Spain Department of Respiratory Medicine, Hospital Universitari Parc Taulí, Sabadell, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Gallego
authors.affiliation: Department of Microbiology, Hospital Universitari Parc Taulí, Sabadell, Spain.
authors.forename: Mateu
authors.initials: M
authors.lastname: Espasa
authors.affiliation: Genomics and Health Area, Centro Superior de Investigación en Salud Pública- Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunidad Valenciana (CSISP-FISABIO), Valencia, Spain CIBER Epidemiología y Salud Pública (CIBERESP), Barcelona, Spain Department of Genetics, Institut Cavanilles de Biodiversitat i Biologia Evolutiva (ICBiBE), Universitat de València, Valencia, Spain.
authors.forename: Andrés
authors.initials: A
authors.lastname: Moya
authors.affiliation: Fundació Parc Taulí, Sabadell/Badalona, Spain CIBER de Enfermedades Respiratorias (CIBERES), Bunyola, Spain Universitat Autonoma de Barcelona, Esfera (UAB), Barcelona, Spain Department of Respiratory Medicine, Hospital Universitari Parc Taulí, Sabadell, Spain.
authors.forename: Eduard
authors.initials: E
authors.lastname: Monsó
mesh_terms: D000368:Aged; D000818:Animals; D001419:Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D016000:Cluster Analysis; D003430:Cross-Sectional Studies; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D005260:Female; D006801:Humans; D008297:Male; D064307:Microbiota; D008875:Middle Aged; D008969:Molecular Sequence Data; D010802:Phylogeny; D029424:Pulmonary Disease, Chronic Obstructive / Q000382:microbiology* / Q000473:pathology*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013183:Sputum / Q000382:microbiology
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S