Related Experiment Videos
A murine model of chronic mucosal colonization by Pseudomonas aeruginosa
G B Pier1, G Meluleni, E Neuger
1Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115.
Abstract:
Chronic mucosal colonization by Pseudomonas aeruginosa is an integral part of the pathologic process associated with disease due to infection with this organism. We have adapted the streptomycin-treated murine model of chronic mucosal colonization by enteric pathogens to study colonization by P. aeruginosa. Mice first received 1 mg of streptomycin per ml of drinking water for 2 to 5 days and then ingested 10(7) CFU of P. aeruginosa per ml of drinking water for a minimum of 5 days. The result of this regimen was chronic mucosal colonization with P. aeruginosa for up to 10 weeks, which was determined by fecal cultures and confirmed by culture of the intestines after killing of the experimental animals. Bacterial counts were highest in the cecum and colon, with some evidence for extraintestinal bacterial translocation as well. Use of P. aeruginosa mutants deficient in the production of colonization factors such as pili and those dependent on the rpoN gene product resulted in a lower level of chronic colonization. Immune responses to type-specific lipopolysaccharide, pili, and flagellar antigens were measured, and increases in both serum and intestinal antibodies were usually elicited when a strain elaborated a given antigen. This model represents an easy method of routinely achieving chronic mucosal colonization by P. aeruginosa and should prove useful for the study of both bacterial virulence factors and host responses associated with this infectious process.
Insights
This study establishes a new mouse model for chronic Pseudomonas aeruginosa mucosal colonization, crucial for understanding bacterial infections and host immune responses.
Area of Science:
- Microbiology
- Immunology
- Infectious Diseases
Background:
- Chronic mucosal colonization by Pseudomonas aeruginosa is a key factor in associated diseases.
- Studying this colonization requires effective experimental models.
Purpose of the Study:
- To adapt and validate a streptomycin-treated murine model for chronic Pseudomonas aeruginosa mucosal colonization.
- To investigate bacterial virulence factors and host immune responses in this model.
Main Methods:
- Mice received streptomycin in drinking water, followed by P. aeruginosa ingestion.
- Chronic colonization was assessed via fecal and intestinal cultures.
- Bacterial translocation and immune responses to specific antigens were measured.
Main Results:
- The regimen successfully induced chronic P. aeruginosa colonization for up to 10 weeks.
- Highest bacterial counts were observed in the cecum and colon.
- Mutants lacking colonization factors showed reduced colonization; immune responses were elicited by specific antigens.
Conclusions:
- This adapted murine model provides a reliable method for studying chronic P. aeruginosa mucosal colonization.
- The model is valuable for investigating bacterial virulence factors and host immune responses in P. aeruginosa infections.