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Updated: Aug 15, 2026
08:24
Injections of Lipopolysaccharide into Mice to Mimic Entrance of Microbial-derived Products After Intestinal Barrier Breach
Published on: May 2, 2018
Lipopolysaccharide: an endotoxin or an exogenous hormone?
1Interdepartmental Division of Critical Care Medicine, Department of Surgery, University of Toronto, Toronto, Ontario, Canada. marshallj@smh.toronto.on.ca
Summary
Lipopolysaccharide (LPS) is not just a toxin but also an exohormone. Disruptions in the body's LPS recognition system can impair defenses against infections, highlighting its complex role in sepsis.
Area of Science:
- Immunology
- Microbiology
- Evolutionary Biology
Background:
- Sepsis pathogenesis traditionally views microbial products as injurious.
- An evolutionary perspective suggests host-microbial interactions are symbiotic, with disease arising from homeostatic disruption.
Purpose of the Study:
- To re-evaluate the role of lipopolysaccharide (LPS) in sepsis.
- To explore LPS as an exohormone rather than solely an endotoxin.
Main Methods:
- Review of existing literature on LPS recognition and response pathways.
- Analysis of endogenous LPS stores and related mammalian systems.
Main Results:
- LPS exhibits characteristics of a hormone, not just a toxin.
- Mammals possess endogenous LPS, carrier proteins, receptors, and antagonism mechanisms.
- Disruption of LPS recognition compromises host defense against exogenous microbes.
Conclusions:
- LPS functions as both an endotoxin and an exohormone.
- Neutralizing LPS may have variable outcomes, potentially causing benefit or harm.
- Understanding LPS's dual role is crucial for developing effective sepsis therapeutics.
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