Depletion of alveolar macrophages ameliorates virus-induced disease following a pulmonary coronavirus infection

PLoS One. 2014 Mar 7;9(3):e90720. doi: 10.1371/journal.pone.0090720. eCollection 2014.


Coronaviruses cause respiratory disease in humans that can range from mild to severe. However, the pathogenesis of pulmonary coronavirus infections is poorly understood. Mouse hepatitis virus type 1 (MHV-1) is a group 2 coronavirus capable of causing severe morbidity and mortality in highly susceptible C3H/HeJ mice. We have previously shown that both CD4 and CD8 T cells play a critical role in mediating MHV-1-induced disease. Here we evaluated the role of alveolar macrophages (AM) in modulating the adaptive immune response and subsequent disease. Depletion of AM using clodronate liposomes administered prior to MHV-1 infection was associated with a significant amelioration of MHV-1-induced morbidity and mortality. AM depletion resulted in a decreased number of virus-specific CD4 T cells in the lung airways. In addition, a significant increase in the frequency and total number of Tregs in the lung tissue and lung airways was observed following MHV-1 infection in mice depleted of AM. Our results indicate that AM play a critical role in modulating MHV-1-induced morbidity and mortality.

Publication types

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

MeSH terms

  • Animals
  • CD4-Positive T-Lymphocytes / metabolism
  • CD8-Positive T-Lymphocytes / metabolism
  • Cells, Cultured
  • Coronavirus
  • Coronavirus Infections / immunology*
  • Female
  • Lung / immunology
  • Lung / virology
  • Macrophages, Alveolar / immunology*
  • Mice
  • Mice, Inbred C3H
  • Murine hepatitis virus / pathogenicity