title: Phenotypic and molecular characterization of CD103+ CD4+ T cells in bronchoalveolar lavage from patients with interstitial lung diseases.
abstract: BACKGROUND
  The integrin CD103 is preferentially expressed on intraepithelial T lymphocytes, and cells expressing this integrin may play a regulatory role in the microenvironment of the epithelial cell layer.
  
  
  METHODS
  The relative number of CD103(+)/CD4(+) T cells in the bronchoalveolar lavage was significantly elevated in all patients diagnosed with interstitial lung diseases compared with patients with other non-fibrotic disorders of the lung.
  
  
  RESULTS
  Analysis by flow cytometry showed that the CD103(+) and the CD103(-) subpopulations were memory T cells based on the high expression of CD45RO(+). However, the CD103(+)/CD4(+) T cells were CD25(low), CD27(-), CD28(low), and CD62L(-), whereas the CD103(-)/CD4(+) T cells expressed CD25 and CD62L and were CD27(high) and CD28(high). In addition, the CD103(+)/CD4(+) T cells expressed significantly higher quantities of VLA-1 and CD101 than did CD103(-)/CD4(+) T cells. Reverse transcriptase polymerase chain reaction analysis of purified CD103(+) and CD103(-) CD4(+) T cells showed production of tumor necrosis factor (TNF) alpha-R-1 (p55), TNF-alpha-R-2 (p75), interferon gamma, interleukin-10, and TNF-alpha mRNA in both subpopulations. No interleukin-4 mRNA was detected in either subpopulation.
  
  
  CONCLUSIONS
  CD103(+)/CD4(+) T cells represent a T-helper 1-like subpopulation in human lungs with a distinct effector phenotype. Despite the lack of CD27 and the low CD25 and CD28 expression, these cells show a high degree of activation. These results suggest that CD103 expressing CD4 T cells in the lung are continuously activated, long-living cells.
authors.affiliation: Ottawa Health Research Institute, Ottawa, Ontario, Canada. rbraun@ohri.ca
authors.forename: Ruedi K
authors.initials: RK
authors.lastname: Braun
authors.forename: Martin
authors.initials: M
authors.lastname: Foerster
authors.forename: P Reinhard
authors.initials: PR
authors.lastname: Grahmann
authors.forename: Daniela
authors.initials: D
authors.lastname: Haefner
authors.forename: Grefachew
authors.initials: G
authors.lastname: Workalemahu
authors.forename: Claus
authors.initials: C
authors.lastname: Kroegel
mesh_terms: D015703:Antigens, CD / Q000096:biosynthesis / Q000276:immunology*; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology* / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D016207:Cytokines / Q000096:biosynthesis / Q000276:immunology; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D039001:Integrin alpha Chains / Q000096:biosynthesis / Q000276:immunology*; D017493:Leukocyte Common Antigens / Q000096:biosynthesis / Q000276:immunology; D017563:Lung Diseases, Interstitial / Q000276:immunology*; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D015703:Antigens, CD; D016207:Cytokines; D039001:Integrin alpha Chains; D012333:RNA, Messenger; C091367:alpha E integrins; D017493:Leukocyte Common Antigens