Mycoplasma pneumoniae induces host-dependent pulmonary inflammation and airway obstruction in mice

Am J Respir Cell Mol Biol. 2005 Mar;32(3):201-10. doi: 10.1165/rcmb.2004-0197OC. Epub 2004 Dec 30.


Respiratory tract infections result in wheezing in a subset of patients. Mycoplasma pneumoniae is a common etiologic agent of acute respiratory infection in children and adults that has been associated with wheezing in 20-40% of individuals. The current study was undertaken to elucidate the host-dependent pulmonary and immunologic response to M. pneumoniae respiratory infection by studying mice with different immunogenetic backgrounds (BALB/c mice versus C57BL/6 mice). After M. pneumoniae infection, only BALB/c mice developed significant airway obstruction (AO) compared with controls. M. pneumoniae-infected BALB/c mice manifested significantly elevated airway hyperresponsiveness (AHR) compared with C57BL/6 mice 4 and 7 d after inoculation as well as BALB/c control mice. Compared with C57BL/6 mice, BALB/c mice developed worse pulmonary inflammation, including greater peribronchial infiltrates. Infected BALB/c mice had significantly higher concentrations of tumor necrosis factor-alpha, interferon-gamma, interleukin (IL)-1beta, IL-6, IL-12, KC (functional IL-8), and macrophage inflammatory protein 1alpha in the bronchoalveolar lavage fluid compared with infected C57BL/6 mice. No differences in IL-2, IL-4, IL-5, IL-10, and granulocyte/macrophage colony-stimulating factor concentrations were found. The mice in this study exhibited host-dependent infection-related AO and AHR associated with chemokine and T-helper type (Th)1 pulmonary host response and not Th2 response after M. pneumoniae infection.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Airway Obstruction / etiology
  • Airway Obstruction / immunology
  • Airway Obstruction / metabolism
  • Airway Obstruction / microbiology
  • Animals
  • Biomarkers
  • Chemokines / metabolism
  • Inflammation / immunology*
  • Inflammation / metabolism
  • Inflammation / microbiology
  • Lung / immunology
  • Lung / microbiology*
  • Lung / pathology
  • Lung Diseases, Obstructive / etiology
  • Lung Diseases, Obstructive / immunology
  • Lung Diseases, Obstructive / metabolism
  • Lung Diseases, Obstructive / microbiology
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Mycoplasma pneumoniae / immunology*
  • Pneumonia, Mycoplasma / immunology*
  • Pneumonia, Mycoplasma / metabolism


  • Biomarkers
  • Chemokines