title: Expression of mucosa-related integrin alphaEbeta7 on alveolar T cells in interstitial lung diseases.
abstract: The expression of alphaEbeta7 integrin has been related to the selective retention of lymphocytes in mucosal tissues of gut, urogenital tract and lung. To identify potential disease-associated alphaEbeta7 expression patterns on cells accounting for lymphocytic alveolitis in interstitial lung disease (ILD), alphaE expression on CD4+ and CD8+ T cell subsets was evaluated by dual-colour flow cytometry in peripheral blood and bronchoalveolar lavage fluid (BALF) of patients with idiopathic pulmonary fibrosis (IPF; n = 18), hypersensitivity pneumonitis (HP; n = 20) and sarcoidosis (n = 44) in comparison with healthy controls (n = 15). In both healthy individuals and all patient groups the proportion of alphaE-bearing T cells in peripheral blood was < 2%, whereas the vast majority of alveolar CD8+ T cells consistently co-expressed alphaE. Absolute alveolar CD8+alphaE+ cell numbers/ml were up to 30-fold increased in HP patients. Proportions of alphaE-bearing CD4+ cells in BALF were significantly elevated in IPF (74.0 +/- 2.7%) and HP (70.0 +/- 2.4%) compared with normals (30.0 +/- 1.8%) (mean +/- s.e.m.; P < 0.01). In sarcoidosis, the alphaE expression on BALF CD4+ cells displayed subgroup dependency: proportions significantly lower than normal were noted in chest radiographic stage I (14.3 +/- 1.5%), but increased proportions in stages II (50.0 +/- 3.8%) and III (64.0 +/- 4.8%). Correlations between common markers of T cell activation or BALF transforming growth factor-beta (TGF-beta ) bioactivity and alphaE expression were not noted. We conclude that the vast majority of alveolar CD8+ T cells consistently express alphaEbeta7 and that distinct patterns of alphaEbeta7 expression on alveolar CD4+ lymphocytes in sarcoidosis are related to the diverse manifestations of the sarcoid inflammatory process in the lung.
authors.affiliation: Department of Internal Medicine, Justus-Liebig-University, Giessen, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Lohmeyer
authors.forename: J
authors.initials: J
authors.lastname: Friedrich
authors.forename: F
authors.initials: F
authors.lastname: Grimminger
authors.forename: U
authors.initials: U
authors.lastname: Maus
authors.forename: R
authors.initials: R
authors.lastname: Tenter
authors.forename: H
authors.initials: H
authors.lastname: Morr
authors.forename: H G
authors.initials: HG
authors.lastname: Velcovsky
authors.forename: W
authors.initials: W
authors.lastname: Seeger
authors.forename: S
authors.initials: S
authors.lastname: Rosseau
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000542:Alveolitis, Extrinsic Allergic / Q000276:immunology*; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry*; D015496:CD4-Positive T-Lymphocytes / Q000737:chemistry*; D018414:CD8-Positive T-Lymphocytes / Q000737:chemistry*; D005260:Female; D006801:Humans; D016023:Integrins / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011658:Pulmonary Fibrosis / Q000276:immunology*; D012507:Sarcoidosis / Q000276:immunology*; D016212:Transforming Growth Factor beta / Q000032:analysis
chemical_list: D016023:Integrins; D016212:Transforming Growth Factor beta; C070709:integrin alphaEbeta7