Alveolar macrophage dynamics in murine lung regeneration

J Cell Physiol. 2012 Sep;227(9):3208-15. doi: 10.1002/jcp.24009.


In most mammalian species, the removal of one lung results in dramatic compensatory growth of the remaining lung. To investigate the contribution of alveolar macrophages (AMs) to murine post-pneumonectomy lung growth, we studied bronchoalveolar lavage (BAL)-derived AM on 3, 7, 14 and 21 days after left pneumonectomy. BAL demonstrated a 3.0-fold increase in AM (CD45(+), CD11b(-), CD11c(+), F4/80(+), Gr-1(-)) by 14 days after pneumonectomy. Cell cycle flow cytometry of the BAL-derived cells demonstrated an increase in S + G2 phase cells on days 3 (11.3 ± 2.7%) and 7 (12.1 ± 1.8%) after pneumonectomy. Correspondingly, AM demonstrated increased expression of VEGFR1 and MHC class II between days 3 and 14 after pneumonectomy. To investigate the potential contribution of peripheral blood cells to this AM population, parabiotic mice (wild-type/GFP) underwent left pneumonectomy. Analysis of GFP(+) cells in the post-pneumonectomy lung demonstrated that by day 14, less than 1% of the AM population were derived from the peripheral blood. Finally, AM gene transcription demonstrated a significant shift from decreased transcription of angiogenesis-related genes on day 3 to increased transcription on day 7 after pneumonectomy. The increased number of locally proliferating AM, combined with their growth-related gene transcription, suggests that AM actively participate in compensatory lung growth.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bronchoalveolar Lavage
  • Cell Count
  • Gene Expression
  • Genes, MHC Class II
  • Lung / physiology*
  • Macrophages, Alveolar / cytology*
  • Macrophages, Alveolar / metabolism*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Neovascularization, Physiologic / genetics
  • Pneumonectomy / methods
  • Regeneration*
  • Vascular Endothelial Growth Factor Receptor-1 / genetics
  • Vascular Endothelial Growth Factor Receptor-1 / metabolism


  • Vascular Endothelial Growth Factor Receptor-1