title: Co-culture of human bronchial fibroblasts and CD4+ T cells increases Th17 cytokine signature.
abstract: BACKGROUND
  Airway inflammation is an important characteristic of asthma and has been associated with airway remodelling and bronchial hyperreactivity. The mucosal microenvironment composed of structural cells and highly specialised extracellular matrix is able to amplify and promote inflammation. This microenvironment leads to the development and maintenance of a specific adaptive response characterized by Th2 and Th17. Bronchial fibroblasts produce multiple mediators that may play a role in maintaining and amplifying this response in asthma.
  
  
  OBJECTIVE
  To investigate the role of bronchial fibroblasts obtained from asthmatic subjects and healthy controls in regulating Th17 response by creating a local micro-environment that promotes this response in the airways.
  
  
  METHODS
  Human bronchial fibroblasts and CD4(+)T cells were isolated from atopic asthmatics and non-atopic healthy controls. CD4(+)T were co-cultured with bronchial fibroblasts of asthmatic subjects and healthy controls. RORc gene expression was detected by qPCR. Phosphorylated STAT-3 and RORγt were evaluated by western blots. Th17 phenotype was measured by flow cytometry. IL-22, IL17, IL-6 TGF-β and IL1-β were assessed by qPCR and ELISA.
  
  
  RESULTS
  Co-culture of CD4(+)T cells with bronchial fibroblasts significantly stimulated RORc expression and induced a significant increase in Th17 cells as characterized by the percentage of IL-17(+)/CCR6(+) staining in asthmatic conditions. IL-17 and IL-22 were increased in both normal and asthmatic conditions with a significantly higher amount in asthmatics compared to controls. IL-6, IL-1β, TGF-β and IL-23 were significantly elevated in fibroblasts from asthmatic subjects upon co-culture with CD4(+)T cells. IL-23 stimulates IL-6 and IL-1β expression by bronchial fibroblasts.
  
  
  CONCLUSIONS
  Interaction between bronchial fibroblasts and T cells seems to promote specifically Th17 cells profile in asthma. These results suggest that cellular interaction particularly between T cells and fibroblasts may play a pivotal role in the regulation of the inflammatory response in asthma.
authors.affiliation: Centre de recherche, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada.
authors.forename: Lionel
authors.initials: L
authors.lastname: Loubaki
authors.affiliation: Centre de recherche, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada.
authors.forename: Ikhlass
authors.initials: I
authors.lastname: Hadj-Salem
authors.affiliation: Centre de recherche, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada.
authors.forename: Raouia
authors.initials: R
authors.lastname: Fakhfakh
authors.affiliation: Centre de recherche, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada.
authors.forename: Eric
authors.initials: E
authors.lastname: Jacques
authors.affiliation: Centre de recherche, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada.
authors.forename: Sophie
authors.initials: S
authors.lastname: Plante
authors.affiliation: Centre de recherche en rhumatologie et Immunologie, Université Laval, Québec, Canada.
authors.forename: Marc
authors.initials: M
authors.lastname: Boisvert
authors.affiliation: Centre de recherche en rhumatologie et Immunologie, Université Laval, Québec, Canada.
authors.forename: Fawzi
authors.initials: F
authors.lastname: Aoudjit
authors.affiliation: Centre de recherche, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada.
authors.forename: Jamila
authors.initials: J
authors.lastname: Chakir
mesh_terms: D000328:Adult; D001249:Asthma / Q000235:genetics* / Q000276:immunology / Q000473:pathology*; D001980:Bronchi / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000473:pathology*; D016022:Case-Control Studies; D060833:Cellular Microenvironment; D018920:Coculture Techniques; D005260:Female; D005347:Fibroblasts / Q000276:immunology / Q000473:pathology*; D005786:Gene Expression Regulation / Q000276:immunology; D006801:Humans; D020381:Interleukin-17 / Q000235:genetics / Q000276:immunology*; D053583:Interleukin-1beta / Q000235:genetics / Q000276:immunology; D015850:Interleukin-6 / Q000235:genetics / Q000276:immunology; D007378:Interleukins / Q000235:genetics / Q000276:immunology; D008297:Male; D008875:Middle Aged; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3 / Q000235:genetics / Q000276:immunology; D010766:Phosphorylation; D061251:Primary Cell Culture; D054399:Receptors, CCR6 / Q000235:genetics / Q000276:immunology; D050796:STAT3 Transcription Factor / Q000235:genetics / Q000276:immunology; D015398:Signal Transduction; D016212:Transforming Growth Factor beta / Q000235:genetics / Q000276:immunology; D000097043:Interleukin-22
chemical_list: D020381:Interleukin-17; D053583:Interleukin-1beta; D015850:Interleukin-6; D007378:Interleukins; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3; D054399:Receptors, CCR6; D050796:STAT3 Transcription Factor; D016212:Transforming Growth Factor beta; D000097043:Interleukin-22; C106311:CCR6 protein, human; C539900:RORC protein, human; C494086:STAT3 protein, human