Related Experiment Video
Updated: Oct 6, 2026
Co-culture Models of Pseudomonas aeruginosa Biofilms Grown on Live Human Airway Cells
Published on: October 7, 2010
Adherence to and penetration of human intestinal Caco-2 epithelial cell monolayers by Pseudomonas aeruginosa
Y Hirakata1, K Izumikawa, T Yamaguchi
1Department of Laboratory Medicine, Nagasaki University School of Medicine, Sakamoto, Japan. hirakata@net.nagasaki-u.ac.jp
Abstract:
Clinical isolates of Pseudomonas aeruginosa from blood adhered to and penetrated intestinal Caco-2 cell monolayers to a greater degree than did isolates from sputum, with a concomitant drastic decrease in transepithelial electrical resistance. PAO-PR1, an avirulent exotoxin A mutant of PAO1, did not cause a decrease in the resistance. The Caco-2 monolayer system may be useful for the evaluation of certain P. aeruginosa virulence factor activities.
Insights
Clinical Pseudomonas aeruginosa from blood, unlike sputum isolates, readily invade intestinal cells and disrupt barrier function. This suggests a potential method for evaluating bacterial virulence factors.
Area of Science:
- Microbiology
- Cell Biology
- Infectious Diseases
Background:
- Pseudomonas aeruginosa is an opportunistic pathogen causing various infections.
- Understanding P. aeruginosa virulence factors is crucial for developing effective treatments.
- Intestinal epithelial barriers play a key role in host defense against pathogens.
Purpose of the Study:
- To investigate the adherence and invasion capabilities of clinical Pseudomonas aeruginosa isolates from different sources (blood vs. sputum) using an in vitro intestinal model.
- To assess the impact of P. aeruginosa isolates on intestinal epithelial barrier integrity.
- To evaluate the utility of the Caco-2 cell monolayer system for studying bacterial virulence.
Main Methods:
- Utilized Caco-2 cell monolayers as an in vitro model of the intestinal epithelium.
- Quantified adherence and penetration of Pseudomonas aeruginosa isolates from blood and sputum.
- Measured transepithelial electrical resistance (TEER) to assess barrier function.
- Tested an avirulent exotoxin A mutant (PAO-PR1) of P. aeruginosa PAO1.
Main Results:
- Clinical isolates of P. aeruginosa from blood demonstrated significantly higher adherence to and penetration of Caco-2 cell monolayers compared to isolates from sputum.
- Exposure to blood-derived P. aeruginosa isolates caused a substantial decrease in transepithelial electrical resistance, indicating severe disruption of the intestinal barrier.
- The avirulent exotoxin A mutant PAO-PR1 did not induce a significant decrease in transepithelial electrical resistance, suggesting the role of exotoxin A in virulence.
- The Caco-2 cell model effectively differentiated the virulence potential of P. aeruginosa isolates.
Conclusions:
- Clinical Pseudomonas aeruginosa isolates from bloodstream infections exhibit enhanced ability to breach intestinal epithelial barriers compared to respiratory isolates.
- The Caco-2 cell monolayer system serves as a valuable tool for evaluating the virulence of P. aeruginosa, particularly its effects on intestinal barrier function.
- Exotoxin A appears to be a significant virulence factor contributing to the disruption of intestinal epithelial integrity by P. aeruginosa.
