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Enteric Bacterial Invasion Of Intestinal Epithelial Cells In Vitro Is Dramatically Enhanced Using a Vertical Diffusion Chamber Model
Published on: October 22, 2013
Campylobacter jejuni cocultured with epithelial cells reduces surface capsular polysaccharide expression
N Corcionivoschi1, M Clyne, A Lyons
1The Children's Research Centre, Our Lady's Children's Hospital, Crumlin, Dublin 12, Ireland.
Infection and Immunity
|March 11, 2009
Summary
Campylobacter jejuni reduces its surface polysaccharides when interacting with human epithelial cells. This bacterial adaptation impacts pathogenicity, suggesting a communication mechanism during infection.
Area of Science:
- Microbiology
- Cell Biology
- Infectious Diseases
Background:
- The host cell environment significantly influences bacterial pathogenicity.
- Understanding host-pathogen interactions is crucial for controlling infections.
Purpose of the Study:
- To investigate the impact of epithelial cell coculture on Campylobacter jejuni polysaccharide expression.
- To elucidate the mechanisms underlying changes in bacterial surface polysaccharides.
Main Methods:
- Coculture of Campylobacter jejuni with HCT-8 epithelial cells.
- Analysis of polysaccharide expression using cellular and molecular techniques, including microarray profiling.
- Experiments with conditioned media and various treatments (Proteinase K, heat, formaldehyde, cycloheximide, chloramphenicol).
Main Results:
- Coculture led to a significant reduction in membrane-bound high-molecular-weight polysaccharide and downregulation of capsular polysaccharide (CPS) locus genes.
- Sugar depletion was dependent on direct bacterial-epithelial cell coculture and specific to C. jejuni-derived conditioned media.
- The effect was abrogated by treatments targeting proteins or host cell viability, but not by mutations in fliQ or luxS genes.
- Passaged C. jejuni exhibited reduced invasiveness and increased serum sensitivity.
Conclusions:
- Campylobacter jejuni actively alters its surface polysaccharides in response to epithelial cell contact.
- A cross-talk mechanism between bacteria and host cells modulates CPS expression.
- These alterations in polysaccharide expression likely contribute to changes in bacterial pathogenicity during infection.
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