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Updated: Jul 4, 2026
08:14
Isolation and Flow Cytometric Characterization of Murine Small Intestinal Lymphocytes
Published on: May 8, 2016
The tiny conductor: immune regulation via commensal organisms
Suzanne L Cassel1, Fayyaz S Sutterwala, Richard A Flavell
1Division of Allergy and Immunology, University of Iowa, Iowa City, IA 52242, USA. fayyaz-sutterwala@uiowa.edu
Cell Host & Microbe
|June 11, 2008
Summary
Specific molecules on Bacteroides fragilis surfaces guide the host immune system, explaining gut microbe tolerance. This research clarifies how beneficial gut bacteria coexist with the host immune system.
Area of Science:
- Microbiology
- Immunology
- Gastroenterology
Background:
- The mammalian gut hosts a dense microbial population, raising questions about immune tolerance.
- The beneficial roles of gut microbes are established, but the underlying mechanisms remain unclear.
Purpose of the Study:
- To investigate the mechanisms by which gut microbes are tolerated by the host immune system.
- To identify specific microbial components involved in host-microbe interactions within the gut.
Main Methods:
- The study focused on the bacterium Bacteroides fragilis.
- Analysis of surface moieties (molecules) of Bacteroides fragilis.
- Investigating the interaction between these moieties and the host immune response.
Main Results:
- Specific moieties on the surface of Bacteroides fragilis were identified.
- These surface molecules were shown to direct the host's immune response.
- This interaction facilitates the tolerance of gut colonization.
Conclusions:
- Bacteroides fragilis possesses surface structures that modulate the host immune system.
- These microbial components are key to establishing immune tolerance in the gut.
- The findings provide a mechanistic explanation for gut microbial colonization in immunocompetent hosts.
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