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A Robust Pneumonia Model in Immunocompetent Rodents to Evaluate Antibacterial Efficacy against S. pneumoniae, H. influenzae, K. pneumoniae, P. aeruginosa or A. baumannii
09:17

A Robust Pneumonia Model in Immunocompetent Rodents to Evaluate Antibacterial Efficacy against S. pneumoniae, H. influenzae, K. pneumoniae, P. aeruginosa or A. baumannii

Published on: January 2, 2017

The acute-phase response and serum amyloid A inhibit the inflammatory response to Acinetobacter baumannii Pneumonia

Rosemarijn Renckens1, Joris J T H Roelofs, Sylvia Knapp

  • 1Laboratory of Experimental Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. r.renckens@amc.uva.nl

The Journal of Infectious Diseases
|December 20, 2005
PubMed
Abstract

Insights

The acute-phase response, including serum amyloid A (SAA), impairs the immune system

Area of Science:

  • Immunology
  • Microbiology

Background:

  • Acinetobacter baumannii is a growing cause of hospital-acquired pneumonia.
  • Patients with trauma or post-surgery are vulnerable to pneumonia due to acute-phase protein response.

Purpose of the Study:

  • Investigate how the acute-phase response affects lung defense against A. baumannii.
  • Determine the role of serum amyloid A (SAA) in pneumonia.

Main Methods:

  • Mice were injected with turpentine (to induce acute-phase response) or saline.
  • Mice were intranasally inoculated with A. baumannii 2 or 5 days post-injection.
  • Measured inflammatory markers, neutrophil influx, and bacterial clearance.

Main Results:

  • Turpentine injection increased SAA and serum amyloid P levels.
  • Inflammatory response to A. baumannii was reduced in turpentine-injected mice.
  • Impaired bacterial clearance and lower pulmonary inflammation were observed.

Conclusions:

  • The acute-phase response and SAA may inhibit inflammation against A. baumannii pneumonia.
  • This inhibition could promote bacterial growth in the lungs.

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