Authors:Einar M. H. Martinsen ,Tomas M. L. Eagan, Elise O. Leiten, Ingvild Haaland, Gunnar R. Husebø, Kristel S. Knudsen, Christine Drengenes, Walter Sanseverino, Andreu Paytuví-Gallart, Rune Nielsen

Institutions:

  • Department of Clinical Science, University of Bergen, Bergen, Norway
  • Department of Thoracic Medicine, Haukeland University Hospital, Bergen, Norway
  • Sequentia Biotech SL, Barcelona, Spain

Publication: PloS One

Date: April 2021

Full paper: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0248967

Abstract:

Background
The fungal part of the pulmonary microbiome (mycobiome) is understudied. We report the composition of the oral and pulmonary mycobiome in participants with COPD compared to controls in a large-scale single-centre bronchoscopy study (MicroCOPD).

Methods
Oral wash and bronchoalveolar lavage (BAL) was collected from 93 participants with COPD and 100 controls. Fungal DNA was extracted before sequencing of the internal transcribed spacer 1 (ITS1) region of the fungal ribosomal RNA gene cluster. Taxonomic barplots were generated, and we compared taxonomic composition, Shannon index, and beta diversity between study groups, and by use of inhaled steroids.

Results
The oral and pulmonary mycobiomes from controls and participants with COPD were dominated by Candida, and there were more Candida in oral samples compared to BAL for both study groups. Malassezia and Sarocladium were also frequently found in pulmonary samples. No consistent differences were found between study groups in terms of differential abundance/distribution. Alpha and beta diversity did not differ between study groups in pulmonary samples, but beta diversity varied with sample type. The mycobiomes did not seem to be affected by use of inhaled steroids.

Conclusion
Oral and pulmonary samples differed in taxonomic composition and diversity, possibly indicating the existence of a pulmonary mycobiome.