The Nasal Microbiome in Asthma

Publication date: Available online 5 March 2018
Source:Journal of Allergy and Clinical Immunology
Author(s): Mina Fazlollahi, Tricia D. Lee, Jade Andrade, Kasopefoluwa Oguntuyo, Yoojin Chun, Galina Grishina, Alexander Grishin, Supinda Bunyavanich
BackgroundNasal microbiota may influence asthma pathobiology.ObjectiveWe sought to characterize the nasal microbiome of subjects with exacerbated asthma, non-exacerbated asthma, and healthy controls to identify nasal microbiota associated with asthma activity.Methods16S rRNA sequencing was performed on nasal swabs obtained from 72 primarily adult subjects with exacerbated asthma (n=20), non-exacerbated asthma (n=31), and healthy controls (n=21). Analyses were performed using QIIME, LEfSe, PICRUSt, and STAMP. Species found to be associated with asthma activity were validated using quantitative PCR. Metabolic pathways associated with differentially abundant nasal taxa were also inferred through metagenomic functional prediction.ResultsNasal bacterial composition significantly differed between subjects with exacerbated asthma, non-exacerbated asthma, and healthy controls (PERMANOVA P=2.2x10^-2). Relative to controls, the nasal microbiota of subjects with asthma were enriched with taxa from Bacteroidetes (Wilcoxon-Mann-Whitney r=0.33, P=5.1x10^-3) and Proteobacteria (r=0.29, P=1.4x10^-2). Four species were differentially abundant based on asthma status after correction for multiple comparisons: Prevotella buccalis, Padj=1.0x10^-2; Dialister invisus, Padj=9.1x10^-3; Gardnerella vaginalis, Padj=2.8x10^-3; Alkanindiges hongkongensis, Padj=2.6x10^-3. These phyla and species were also differentially abundant based on asthma activity (exacerbated asthma vs. non-exacerbated asthma vs. controls). qPCR confirmed species overrepresentation in asthma relative to controls for Prevotella buccalis (fold change=130, P=2.1x10^-4) and Gardnerella vaginalis (fold change 160, P=6.8x10^-4). Metagenomic inference revealed differential glycerolipid metabolism (Kruskal-Wallis P=1.9x10^-4) based on asthma activity.ConclusionNasal microbiome composition differs in subjects with exacerbated asthma, non-exacerbated asthma, and healthy controls. The identified nasal taxa could be further investigated for potential mechanistic roles in asthma and as possible biomarkers of asthma activity.

Graphical abstract

Teaser

Upper airway microbiota may play a role in asthma pathobiology. This study characterized the nasal microbiome of subjects with exacerbated asthma, non-exacerbated asthma, and healthy controls, identifying bacterial taxa associated with asthma and asthma activity.


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