title: Alveolar epithelial dynamics in postpneumonectomy lung growth.
abstract: The intimate anatomic and functional relationship between epithelial cells and endothelial cells within the alveolus suggests the likelihood of a coordinated response during postpneumonectomy lung growth. To define the population dynamics and potential contribution of alveolar epithelial cells to alveolar angiogenesis, we studied alveolar Type II and I cells during the 21 days after pneumonectomy. Alveolar Type II cells were defined and isolated by flow cytometry using a CD45(-) , MHC class II(+) , phosphine(+) phenotype. These phenotypically defined alveolar Type II cells demonstrated an increase in cell number after pneumonectomy; the increase in cell number preceded the increase in Type I (T1α(+) ) cells. Using a parabiotic wild type/GFP pneumonectomy model, <3% of the Type II cells and 1% of the Type I cells were positive for GFP-a finding consistent with the absence of a blood-borne contribution to alveolar epithelial cells. The CD45(-) , MHC class II(+) , phosphine(+) Type II cells demonstrated the active transcription of angiogenesis-related genes both before and after pneumonectomy. When the Type II cells on Day 7 after pneumonectomy were compared to nonsurgical controls, 10 genes demonstrated significantly increased expression (P<0.05). In contrast to the normal adult Type II cells, there was notable expression of inflammation-associated genes (Ccl2, Cxcl2, Ifng) as well as genes associated with epithelial growth (Ereg, Lep). Together, the data suggest an active contribution of local alveolar Type II cells to alveolar growth.
authors: Laboratory of Adaptive and Regenerative Biology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
authors: Kenji
authors: K
authors: Chamoto
authors: Barry C
authors: BC
authors: Gibney
authors: Maximilian
authors: M
authors: Ackermann
authors: Grace S
authors: GS
authors: Lee
authors: Moritz A
authors: MA
authors: Konerding
authors: Akira
authors: A
authors: Tsuda
authors: Steven J
authors: SJ
authors: Mentzer
mesh_terms: D056809:Alveolar Epithelial Cells / Q000276:immunology / Q000378:metabolism / Q000648:ultrastructure; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D049109:Cell Proliferation; D002469:Cell Separation / Q000379:methods; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics; D000949:Histocompatibility Antigens Class II / Q000378:metabolism; D007249:Inflammation / Q000235:genetics; D017493:Leukocyte Common Antigens / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D046529:Microscopy, Electron, Transmission; D018919:Neovascularization, Physiologic / Q000235:genetics; D010227:Parabiosis; D010641:Phenotype; D010720:Phosphines / Q000378:metabolism; D011013:Pneumonectomy; D011650:Pulmonary Alveoli / Q000098:blood supply / Q000254:growth & development* / Q000276:immunology / Q000378:metabolism / Q000601:surgery* / Q000648:ultrastructure; D012038:Regeneration / Q000235:genetics; D013997:Time Factors; D014158:Transcription, Genetic
chemical_list: D015415:Biomarkers; D000949:Histocompatibility Antigens Class II; D010720:Phosphines; D049452:Green Fluorescent Proteins; D017493:Leukocyte Common Antigens; C516770:Ptprc protein, mouse; C044646:phosphine