title: T regulatory cells in stable posttransplant bronchiolitis obliterans syndrome.
abstract: BACKGROUND
  Obliterative bronchiolitis (OB), mainly mediated by T cells, remains the major cause of morbidity and death in long-term lung transplant. Acute rejection (AR), also a T-cell mediated process, is strongly linked to OB. For unknown reasons, several patients with OB halt their pulmonary function decline and stabilize their obstructive defect for a long period. Our aim was to assess the T-cell activation in blood, induced sputum, and broncho-alveolar lavage during AR, stable OB (sOB), and evolving OB (eOB).
  
  
  METHODS
  T-cell phenotype and cytokine production were assessed by flow cytometry in these three compartments. Interleukin-4, interferon-gamma and transforming growth factor (TGF)-beta levels were measured by enzyme-linked immunosorbent assay in blood cell culture supernatants. Results were compared between healthy lung transplant recipients and AR (n=7), sOB (n=7), and eOB (n=13).
  
  
  RESULTS
  Stable and evolutive OB were characterized by a Treg, Th1, and Th2 activation, but compared to eOB, Treg and Th2 cells predominated in sOB. A clear Th1 activation was observed in AR. TGF-beta was increased in AR and evolving OB.
  
  
  CONCLUSIONS
  These preliminary results indicate a contrasted T-cell activation profile depending on the clinical conditions. We speculate that Treg cells could counterbalance the Th0 activation seen in evolving OB and participate in stabilization of airway obstruction.
authors.affiliation: UPRES 3287, IPHM IFR125, Faculté de Médecine, Université de Méditerranée, Marseille, France.
authors.forename: Emilie
authors.initials: E
authors.lastname: Mamessier
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Lorec
authors.forename: Pascal
authors.initials: P
authors.lastname: Thomas
authors.forename: Monique
authors.initials: M
authors.lastname: Badier
authors.forename: Antoine
authors.initials: A
authors.lastname: Magnan
authors.forename: Martine
authors.initials: M
authors.lastname: Reynaud-Gaubert
mesh_terms: D000293:Adolescent; D000328:Adult; D015703:Antigens, CD / Q000096:biosynthesis; D000945:Antigens, Differentiation, T-Lymphocyte / Q000096:biosynthesis; D001989:Bronchiolitis Obliterans / Q000209:etiology / Q000276:immunology*; D017252:CD3 Complex / Q000096:biosynthesis; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D015847:Interleukin-4 / Q000378:metabolism; D037181:Lectins, C-Type; D016040:Lung Transplantation / Q000009:adverse effects / Q000379:methods; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011183:Postoperative Complications; D013577:Syndrome; D050378:T-Lymphocytes, Regulatory / Q000166:cytology* / Q000276:immunology; D018417:Th1 Cells / Q000378:metabolism; D018418:Th2 Cells / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000378:metabolism; D000099192:CD69 Antigens
chemical_list: D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D017252:CD3 Complex; D007371:Interferon-gamma; D015847:Interleukin-4; D037181:Lectins, C-Type; D016212:Transforming Growth Factor beta; D000099192:CD69 Antigens