A polymicrobial perspective of pulmonary infections exposes an enigmatic pathogen in cystic fibrosis patients

Related Experiment Video

Updated: Jun 30, 2026

Growing a Cystic Fibrosis-Relevant Polymicrobial Biofilm to Probe Community Phenotypes
03:53

Growing a Cystic Fibrosis-Relevant Polymicrobial Biofilm to Probe Community Phenotypes

Published on: April 19, 2024

Christopher D Sibley1, Michael D Parkins, Harvey R Rabin

  • 1Department of Microbiology and Infectious Diseases, University of Calgary, Calgary, AB, Canada T2N 4N1.

Proceedings of the National Academy of Sciences of the United States of America
|September 25, 2008
PubMed

Insights

Cystic fibrosis (CF) lung infections involve complex microbial communities. The Streptococcus milleri group (SMG) is a dominant pathogen during acute exacerbations, suggesting new therapeutic targets for CF lung disease.

Area of Science:

  • Microbiology
  • Pulmonology
  • Infectious Diseases

Background:

  • Lung disease is a primary cause of morbidity and mortality in cystic fibrosis (CF) patients.
  • CF airway infections are increasingly recognized as polymicrobial, involving complex microbial communities.
  • Understanding these dynamics is crucial for effective CF patient management.

Purpose of the Study:

  • To comprehensively assess the polymicrobial community composition and dynamics in CF lung infections.
  • To investigate the role of the Streptococcus milleri group (SMG) in CF pulmonary exacerbations.
  • To explore alternative therapeutic strategies targeting microbial community composition.

Main Methods:

  • Longitudinal study design.
  • Utilized both culture-independent and microbiological approaches.
  • Analyzed microbial community composition and dynamics over time.

Main Results:

  • Demonstrated complex and dynamic microbial communities within CF lungs.
  • Identified the Streptococcus milleri group (SMG) as a numerically dominant pathogen during 39% of acute pulmonary exacerbations.
  • Showcased SMG's ability to establish chronic pulmonary infections in CF patients.

Conclusions:

  • The Streptococcus milleri group (SMG) plays a significant role in CF pulmonary exacerbations.
  • Managing the overall microbial community composition offers a potential therapeutic avenue for CF lung infections.
  • This research provides a comprehensive view of polymicrobial dynamics in CF lung disease.

More Related Videos

Cystic Fibrosis Aggregate Biofilm Model to Study Infection-relevant Gene Expression08:58

Cystic Fibrosis Aggregate Biofilm Model to Study Infection-relevant Gene Expression

Published on: April 18, 2025

Development of a Polymicrobial Colony Biofilm Model to Test Antimicrobials in Cystic Fibrosis07:16

Development of a Polymicrobial Colony Biofilm Model to Test Antimicrobials in Cystic Fibrosis

Published on: September 20, 2024

Related Concept Videos

Cystic Fibrosis: Pathogenesis01:23

Cystic Fibrosis: Pathogenesis

Cystic fibrosis (CF), an autosomal recessive disorder, significantly affects the function of exocrine glands. This genetically inherited disease is characterized by the production of thick and sticky mucus, which can severely affect various organs and systems in the body.
CF is primarily caused by a genetic mutation in a chromosome 7 gene coding for the cystic fibrosis transmembrane conductance regulator (CFTR) protein. The most common gene mutation leading to CF is the ΔF508 mutation, but...
Cystic Fibrosis: Management01:24

Cystic Fibrosis: Management

Cystic fibrosis (CF) is an autosomal recessive disorder that predominantly affects individuals of Northern European descent, occurring at a rate of 1 in 3500. It is caused by a genetic mutation in a gene on chromosome 7, most commonly the ΔF508 mutation, that codes for the cystic fibrosis transmembrane conductance regulator (CFTR) protein. This results in thicker mucus secretions and obstruction pathologies in multiple organs, including the lungs and sinuses.
Sinus disease and chronic sinusitis...
Microbiota of the Respiratory Tract01:29

Microbiota of the Respiratory Tract

The human respiratory tract, comprising the upper and lower segments, serves as a critical interface with the external environment. The upper respiratory tract (URT)—including the nostrils, sinuses, pharynx, and oropharynx—is heavily colonized by microbes, while the lower respiratory tract (LRT), composed of the larynx, trachea, bronchi, and lungs, was long thought to be sterile. However, recent molecular studies have revealed that the lungs are not devoid of microbes but act more like...
Atypical Pneumonia01:14

Atypical Pneumonia

Atypical pneumonia, often caused by Mycoplasma pneumoniae, is a form of pulmonary infection that differs from the classical presentation of bacterial pneumonia in both its cause and clinical symptoms. Mycoplasma pneumoniae is a pleomorphic bacterium notable for its lack of a rigid cell wall. This structural characteristic imparts resistance to beta-lactam antibiotics and significantly influences the bacterium’s behavior within the human host.Other pathogens responsible for the disease include...
Pneumonia I: Introduction01:29

Pneumonia I: Introduction

Pneumonia is an infection of the lower respiratory tract that leads to inflammation of the lung parenchyma, often resulting in the accumulation of inflammatory exudate in the alveoli and airways. Unlike the watery, low-protein fluid exudate in pulmonary edema, the exudate in this case is a thick fluid rich in immune cells, proteins, and debris produced during infection and inflammation.This impairs gas exchange and can lead to consolidation of lung tissue. The infection may be caused by a...
Pneumonia I: Introduction01:30

Pneumonia I: Introduction

Pneumonia is an acute respiratory infection that targets the lungs, specifically the alveoli. These tiny air sacs, essential for oxygen exchange, become engorged with pus and fluid, severely hindering breathing, decreasing oxygen absorption, and causing significant pain and discomfort during respiration.
Risk Factors
Various factors influence the likelihood of developing pneumonia. Age plays a crucial role, with infants, children under two, and individuals over 65 at increased risk due to their...