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Enterococcus faecalis from healthy infants modulates inflammation through MAPK signaling pathways.
Shugui Wang1, Martin Lloyd Hibberd2, Sven Pettersson3
1Department of Microbiology, National University of Singapore, Singapore, Singapore; Division of Cellular and Molecular Research, National Cancer Centre Singapore, Singapore, Singapore.
Plos One
|May 17, 2014
Summary
Enterococcus faecalis, a common neonatal gut bacterium, suppresses inflammatory responses. This early colonizer helps regulate infant immune system development by reducing pro-inflammatory cytokines like IL-8.
Area of Science:
- Microbiology
- Immunology
- Neonatal Health
Background:
- Commensal bacteria are crucial for infant gastrointestinal and immune development.
- Neonatal gut colonization patterns, starting with Enterococcus, influence immune maturation.
- Enterococcus colonization is linked to allergy development in infants.
Purpose of the Study:
- To investigate the immunomodulatory effects of Enterococcus faecalis in the neonatal gut.
- To understand the role of E. faecalis in regulating inflammatory responses in early life.
Main Methods:
- Isolation of E. faecalis from healthy newborns.
- In vivo and in vitro experiments to assess inflammatory responses.
- Analysis of cytokine secretions and signaling pathways (JNK, p38).
Main Results:
- E. faecalis significantly suppresses inflammatory responses.
- E. faecalis attenuates the secretion of pro-inflammatory cytokines, particularly IL-8.
- Suppression of inflammation is mediated through JNK and p38 signaling pathways.
Conclusions:
- E. faecalis, an early gut colonizer, plays a role in regulating host inflammatory responses.
- This bacterium may contribute to immune tolerance and reduced inflammation in infants.
- Findings highlight the importance of early bacterial colonization in shaping infant immunity.
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