Pseudomonas aeruginosa aggregates in cystic fibrosis sputum produce exopolysaccharides that likely impede current therapies

Laura K. Jennings, Julia E. Dreifus, Courtney Reichhardt, Kelly M. Storek, Patrick R. Secor, Daniel J. Wozniak, Katherine B. Hisert, Matthew R. Parsek

Research output: Contribution to journalArticlepeer-review

87 Scopus citations

Abstract

In cystic fibrosis (CF) airways, Pseudomonas aeruginosa forms cellular aggregates called biofilms that are thought to contribute to chronic infection. To form aggregates, P. aeruginosa can use different mechanisms, each with its own pathogenic implications. However, how they form in vivo is controversial and unclear. One mechanism involves a bacterially produced extracellular matrix that holds the aggregates together. Pel and Psl exopolysaccharides are structural and protective components of this matrix. We develop an immunohistochemical method to visualize Pel and Psl in CF sputum. We demonstrate that both exopolysaccharides are expressed in the CF airways and that the morphology of aggregates is consistent with an exopolysaccharide-dependent aggregation mechanism. We reason that the cationic exopolysaccharide Pel may interact with some of the abundant anionic host polymers in sputum. We show that Pel binds extracellular DNA (eDNA) and that this interaction likely impacts current therapies by increasing antimicrobial tolerance and protecting eDNA from digestion.

Original languageEnglish
Article number108782
JournalCell Reports
Volume34
Issue number8
DOIs
StatePublished - Feb 23 2021

Keywords

  • IHC
  • Pel
  • Pseudomonas aeruginosa biofilm matrix
  • Psl
  • antibiotic susceptibility
  • bacterial aggregation
  • biofilm
  • cystic fibrosis
  • exopolysaccharide
  • extracellular DNA

Fingerprint

Dive into the research topics of 'Pseudomonas aeruginosa aggregates in cystic fibrosis sputum produce exopolysaccharides that likely impede current therapies'. Together they form a unique fingerprint.

Cite this