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11:49
Analysis of the Epithelial Damage Produced by Entamoeba histolytica Infection
Published on: June 12, 2014
Attaching and effacing pathogen-induced tight junction disruption in vivo
Julian A Guttman1, Yuling Li, Mark E Wickham
1The University of British Columbia, Michael Smith Laboratories, 301-2185 East Mall, Vancouver, BC, Canada V6T 1Z4.
Cellular Microbiology
|March 22, 2006
Summary
Diarrhoea from attaching and effacing (A/E) pathogens like E. coli disrupts intestinal tight junctions. This leads to increased colon water content, causing diarrhoea during infection.
Area of Science:
- Microbiology
- Gastroenterology
- Cell Biology
Background:
- Diarrhoea is a key symptom of infections by human attaching and effacing (A/E) pathogens, including enterohaemorrhagic E. coli (EHEC) and enteropathogenic E. coli (EPEC).
- Previous studies suggested A/E pathogens might target tight junctions, crucial for intestinal barrier function, but this remained unproven in natural disease.
Purpose of the Study:
- To investigate the effect of A/E pathogen infection on tight junctions during natural disease.
- To determine if tight junction disruption by A/E pathogens contributes to diarrhoea.
Main Methods:
- Examined morphological alterations of tight junctions in infected colon tissue.
- Utilized molecular tracers to assess epithelial barrier function.
- Investigated the role of the bacterial effector protein EspF in tight junction disruption.
Main Results:
- Demonstrated morphological alteration and functional disruption of tight junctions during A/E pathogen infection.
- Observed increased colon luminal water content correlating with tight junction disruption.
- Showed that the bacterial effector EspF is essential for tight junction disruption and associated water increase.
Conclusions:
- A/E pathogen infection causes morphological and functional disruption of intestinal tight junctions.
- Tight junction disruption contributes to increased colon water content and diarrhoea.
- The bacterial effector EspF plays a critical role in mediating these effects.
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