Time-dependent airway epithelial and inflammatory cell responses induced by influenza virus A/PR/8/34 in C57BL/6 mice

Toxicol Pathol. 2007 Apr;35(3):424-35. doi: 10.1080/01926230701302558.

Abstract

The present study examines the kinetics of airway epithelial remodeling and inflammation in the airways of C57BL/6J mice infected with influenza virus A/PR/8/34 (PR8). Mice were intranasally instilled with 50 plaque forming units (pfu) of virus or its respective vehicle, saline, and then were sacrificed at 3, 7, 10, 15, or 21 days postinfection (dpi). PR8 treatment resulted in airway epithelial cell regeneration as suggested by proliferating cell nuclear antigen (PCNA) positive staining at 7 and 10 dpi and mucous cell metaplasia (MCM) evident at 10, 15, and 21 dpi. PR8 treatment resulted in a classic pattern of inflammation observed in bronchoalveolar lavage fluid (BALF), in which neutrophils peaked at 3 and 7 dpi and monocytes, lymphocytes, and eosinophils peaked at 10 dpi before returning to background levels of detection. Chemokine (MCP-1) and cytokine (IL-6, TNF-alpha, IFN-gamma, IL-5, IL-4, and IL-9) levels peaked at 7 dpi in BALF. IL-13 levels were unaffected by PR8 treatment. Concurrent with inflammation, MUC5AC gene expression was markedly increased by PR8 treatment at 7 dpi. Collectively, the results of this study indicate that the onset of MCM in airway epithelium occurs during the remodeling process and persists after the inflammatory response has diminished.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Bronchoalveolar Lavage Fluid / chemistry
  • Bronchoalveolar Lavage Fluid / cytology
  • Chemokine CCL2 / biosynthesis
  • Cytokines / biosynthesis
  • Eosinophils / immunology*
  • Epithelium / pathology*
  • Epithelium / virology
  • Female
  • Immunohistochemistry
  • Inflammation / immunology*
  • Influenza A virus*
  • Kinetics
  • Leukocyte Elastase / biosynthesis
  • Lung* / pathology
  • Lung* / virology
  • Lymphocytes / immunology*
  • Metaplasia / pathology
  • Mice
  • Mice, Inbred C57BL
  • Monocytes / immunology*
  • Mucin 5AC
  • Mucins / metabolism
  • Neutrophils / immunology*
  • Orthomyxoviridae Infections* / pathology
  • Orthomyxoviridae Infections* / virology
  • Proliferating Cell Nuclear Antigen / metabolism
  • Respiratory Mucosa / immunology
  • Respiratory Mucosa / pathology

Substances

  • Ccl2 protein, mouse
  • Chemokine CCL2
  • Cytokines
  • Muc5ac protein, mouse
  • Mucin 5AC
  • Mucins
  • Proliferating Cell Nuclear Antigen
  • Leukocyte Elastase