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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
PubMed

Insights

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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