title: Dynamic changes of mononuclear phagocytes in circulating, pulmonary alveolar and interstitial compartments in a mouse model of experimental silicosis.
abstract: Silicosis is a devastating, irreversible lung fibrosis condition exposed to crystalline silica. The mononuclear phagocyte system plays an important role in the pathogenesis of silicosis.
  
  
  
  The present study was aimed to explore the dynamic changes of mononuclear phagocytes in circulating, pulmonary alveolar and interstitial compartments in experimental silicosis model.
  
  
  
  A mouse model of lung fibrosis was developed with crystalline silica particles (2 mg/40 μL via oropharyngeal instillation) using male C57BL/6 mice, and were killed on days 1, 3, 7, 14, and 28. The lung inflammation and fibrosis was investigated using hematoxylin-eosin staining and bronchoalveolar lavage fluid (BALF) analysis, Masson's trichrome staining, and immunofluorescence. Circulating monocyte subsets (Ly6C(hi) and Ly6C(lo)), polarization state of BALF-derived alveolar macrophages (AMϕ) and lung interstitial macrophages (IMϕ, derived from enzymatically digested lung tissue) were analyzed by flow cytometry.
  
  
  
  The percentage of Ly6C(hi) monocytes significantly increased on day 1 after silica exposure, which reached the peak level from day 7 till day 28. Moreover, M2 (alternative activation) AMϕ (PI - CD64 + CD206+) was dramatically and progressively increased from day 1 to day 28. A parallel increase in IMϕ with M2 polarization (PI-CD64 + CD11b + CD206+) was also observed from day 1 to day 28.
  
  
  
  Our data demonstrate a dynamic view of mononuclear phagocyte change in three compartments after silica challenge, which highlights the remodeling of mononuclear phagocyte system as a potential therapeutic target for silicosis.
authors.affiliation: a Department of Respiratory and Critical Care Medicine , Pingjin Hospital, Logistics University of the Chinese People's Armed Police Forces , Tianjin , China , and.
authors.forename: Guo-An
authors.initials: GA
authors.lastname: Xiang
authors.affiliation: a Department of Respiratory and Critical Care Medicine , Pingjin Hospital, Logistics University of the Chinese People's Armed Police Forces , Tianjin , China , and.
authors.forename: Yi-Dan
authors.initials: YD
authors.lastname: Zhang
authors.affiliation: a Department of Respiratory and Critical Care Medicine , Pingjin Hospital, Logistics University of the Chinese People's Armed Police Forces , Tianjin , China , and.
authors.forename: Cheng-Cheng
authors.initials: CC
authors.lastname: Su
authors.affiliation: b Tianjin Key Laboratory of Cardiovascular Remodeling and Target Organ Injury, Institute of Cardiovascular Disease and Heart Center, Pingjin Hospital, Logistics University of the Chinese People's Armed Police Forces , Tianjin , China.
authors.forename: Yong-Qiang
authors.initials: YQ
authors.lastname: Ma
authors.affiliation: b Tianjin Key Laboratory of Cardiovascular Remodeling and Target Organ Injury, Institute of Cardiovascular Disease and Heart Center, Pingjin Hospital, Logistics University of the Chinese People's Armed Police Forces , Tianjin , China.
authors.forename: Yu-Ming
authors.initials: YM
authors.lastname: Li
authors.affiliation: b Tianjin Key Laboratory of Cardiovascular Remodeling and Target Organ Injury, Institute of Cardiovascular Disease and Heart Center, Pingjin Hospital, Logistics University of the Chinese People's Armed Police Forces , Tianjin , China.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhou
authors.affiliation: a Department of Respiratory and Critical Care Medicine , Pingjin Hospital, Logistics University of the Chinese People's Armed Police Forces , Tianjin , China , and.
authors.forename: Lu-Qing
authors.initials: LQ
authors.lastname: Wei
authors.affiliation: a Department of Respiratory and Critical Care Medicine , Pingjin Hospital, Logistics University of the Chinese People's Armed Police Forces , Tianjin , China , and.|b Tianjin Key Laboratory of Cardiovascular Remodeling and Target Organ Injury, Institute of Cardiovascular Disease and Heart Center, Pingjin Hospital, Logistics University of the Chinese People's Armed Police Forces , Tianjin , China.
authors.forename: Wen-Jie
authors.initials: WJ
authors.lastname: Ji
mesh_terms: D000818:Animals; D000950:Antigens, Ly / Q000276:immunology; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology* / Q000276:immunology; D004195:Disease Models, Animal; D005434:Flow Cytometry; D008168:Lung / Q000276:immunology / Q000473:pathology*; D016676:Macrophages, Alveolar / Q000276:immunology / Q000473:pathology*; D008297:Male; D008810:Mice, Inbred C57BL; D009000:Monocytes / Q000276:immunology / Q000473:pathology*; D011650:Pulmonary Alveoli / Q000276:immunology / Q000473:pathology*; D012829:Silicosis / Q000097:blood / Q000276:immunology / Q000473:pathology*
chemical_list: D000950:Antigens, Ly; C494192:Ly-6C antigen, mouse
keywords: Lung macrophage; macrophage polarization; monocyte subsets; pulmonary fibrosis; silica