title: Alveolar Macrophages in Allergic Asthma: the Forgotten Cell Awakes.
abstract: OBJECTIVE
  The role of alveolar macrophages in innate immune responses has long been appreciated. Here, we review recent studies evaluating the participation of these cells in allergic inflammation.
  
  
  RESULTS
  Immediately after allergen exposure, monocytes are rapidly recruited from the bloodstream and serve to promote acute inflammation. By contrast, resident alveolar macrophages play a predominantly suppressive role in an effort to restore homeostasis. As inflammation becomes established after repeated exposures, alveolar macrophages can polarize across a continuum of activation phenotypes, losing their suppressive functions and gaining pathogenic functions. Future research should focus on the diverse roles of monocytes/macrophages during various types and phases of allergic inflammation. These properties could lead us to new therapeutic opportunities.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, 6301 MSRB III, 1150 W. Medical Center Drive, Ann Arbor, MI, 48109-5642, USA.
authors.forename: Christina
authors.initials: C
authors.lastname: Draijer
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, 6301 MSRB III, 1150 W. Medical Center Drive, Ann Arbor, MI, 48109-5642, USA. petersm@umich.edu.
authors.forename: Marc
authors.initials: M
authors.lastname: Peters-Golden
mesh_terms: D000818:Animals; D001249:Asthma / Q000276:immunology* / Q000473:pathology; D006801:Humans; D007249:Inflammation / Q000276:immunology / Q000473:pathology; D016676:Macrophages, Alveolar / Q000276:immunology*
keywords: Asthma; Eosinophilic; Inflammation; Macrophage; Neutrophilic; Phenotypes