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Host and microbiota factors that control Klebsiella pneumoniae mucosal colonization in mice

Helen Y Lau1, Gary B Huffnagle, Thomas A Moore

  • 1Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI 48109, USA.

Microbes and Infection
|September 3, 2008
PubMed

Insights

Klebsiella pneumoniae strain IA565 stably colonizes mice nasal and gut tracts. Gut colonization depends on microbiota and inflammation, but IA565 does not worsen colitis.

Area of Science:

  • Microbiology
  • Immunology
  • Gastroenterology

Background:

  • Klebsiella pneumoniae can be a pathogen or commensal.
  • Previous work showed K. pneumoniae strain IA565 (KpIA565) is non-pathogenic in pneumonia models.
  • This study investigates the colonization dynamics of KpIA565 in mice.

Purpose of the Study:

  • To determine colonization patterns of KpIA565 in the nasal cavity and gastrointestinal tract.
  • To elucidate the role of host microbiota and inflammation in KpIA565 colonization.
  • To assess the impact of KpIA565 colonization on host inflammatory responses.

Main Methods:

  • Inoculation of KpIA565 into wild-type and germ-free mice.
  • Intranasal and gastrointestinal tract colonization assessments.
  • Evaluation of colonization during dextran sodium sulfate (DSS) and Citrobacter rodentium-induced colitis models.

Main Results:

  • KpIA565 stably colonized the nasal cavity and gastrointestinal tract for at least 3 weeks.
  • Nasal colonization was independent of the normal nasal microbiota.
  • Gastrointestinal tract colonization was higher in germ-free mice and increased with DSS-induced inflammation.
  • KpIA565 colonization did not affect host histopathology in either colitis model.

Conclusions:

  • KpIA565 demonstrates robust colonization potential in mice.
  • Host microbiota and inflammation significantly influence gastrointestinal tract colonization by KpIA565.
  • KpIA565, as a commensal, does not exacerbate experimental colitis.

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