Antibiotic susceptibility of cystic fibrosis lung microbiome members in a multispecies biofilm

Eva Vandeplassche; Andrea Sass; Lisa Ostyn; Mette Burmølle; Kasper Nørskov Kragh; Thomas Bjarnsholt; Tom Coenye; Aurélie Crabbé

doi:10.1016/j.bioflm.2020.100031

Antibiotic susceptibility of cystic fibrosis lung microbiome members in a multispecies biofilm

Biofilm. 2020 Jun 13:2:100031. doi: 10.1016/j.bioflm.2020.100031. eCollection 2020 Dec.

Authors

Eva Vandeplassche¹, Andrea Sass¹, Lisa Ostyn¹, Mette Burmølle², Kasper Nørskov Kragh³, Thomas Bjarnsholt^{3

4}, Tom Coenye¹, Aurélie Crabbé¹

Affiliations

¹ Laboratory of Pharmaceutical Microbiology, Ghent University, Belgium.
² Department of Microbiology, University of Copenhagen, Denmark.
³ Costerton Biofilm Center, Department of Immunology and Microbiology, University of Copenhagen, Denmark.
⁴ Department of Clinical Microbiology, Copenhagen University Hospital, Denmark.

Abstract

The lungs of cystic fibrosis (CF) patients are often chronically colonized by multiple microbial species that can form biofilms, including the major CF pathogen Pseudomonas aeruginosa. Herewith, lower microbial diversity in CF airways is typically associated with worse health outcomes. In an attempt to treat CF lung infections patients are frequently exposed to antibiotics, which may affect microbial diversity. This study aimed at understanding if common antibiotics that target P. aeruginosa influence microbial diversity. To this end, a microaerophilic multispecies biofilm model of frequently co-isolated members of the CF lung microbiome (Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus anginosus, Achromobacter xylosoxidans, Rothia mucilaginosa, and Gemella haemolysans) was exposed to antipseudomonal antibiotics. We found that antibiotics that affected several dominant species (i.e. ceftazidime, tobramycin) resulted in higher species evenness compared to colistin, which is only active against P. aeruginosa. Furthermore, susceptibility of individual species in the multispecies biofilm following antibiotic treatment was compared to that of the respective single-species biofilms, showing no differences. Adding three anaerobic species (Prevotella melaninogenica, Veillonella parvula, and Fusobacterium nucleatum) to the multispecies biofilm did not influence antibiotic susceptibility. In conclusion, our study demonstrates antibiotic-dependent effects on microbial community diversity of multispecies biofilms comprised of CF microbiome members.

Keywords: Antibiotics; Cystic fibrosis; Microbial diversity; Microbiota; Multispecies biofilms.