title: Proteomic analysis of the airway surface liquid: modulation by proinflammatory cytokines.
abstract: The airway surface is covered by a fluid, the airway surface liquid, interposed between the mucous layer and the epithelium. The airway surface liquid contains proteins, secreted by different cell types, that may have pro-/anti-inflammatory or bactericidal functions or have a role in the mucociliary clearance. We have used a proteomics approach to identify the proteins secreted by an isolated in vitro model of human airway epithelium, at resting and under proinflammatory conditions, as a strategy to define the factors involved in epithelial barrier function. To this aim, we have analyzed the airway surface liquid from human bronchial epithelial cells grown as polarized monolayers in the presence and absence of inflammatory stimuli such as IL-4, IL-1beta, TNF-alpha, and IFN-gamma. Two-dimensional electrophoresis followed by mass spectrometry analysis has allowed the identification of approximately 175 secreted protein spots, among which are immune-related proteins, structural proteins, an actin severer, some protease inhibitors, and a metalloproteinase. Comparisons between treated and untreated conditions have shown that the expression of several proteins was significantly modified by the different cytokines. Our results indicate that the surface epithelium is an active player in the epithelial barrier function and that inflammatory conditions may modulate protein secretion.
authors.affiliation: Laboratorio di Genetica Molecolare, Istituto Giannina Gaslini, Largo G. Gaslini 5, Genoa 16148, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Candiano
authors.forename: Maurizio
authors.initials: M
authors.lastname: Bruschi
authors.forename: Nicoletta
authors.initials: N
authors.lastname: Pedemonte
authors.forename: Luca
authors.initials: L
authors.lastname: Musante
authors.forename: Roberto
authors.initials: R
authors.lastname: Ravazzolo
authors.forename: Sabrina
authors.initials: S
authors.lastname: Liberatori
authors.forename: Luca
authors.initials: L
authors.lastname: Bini
authors.forename: Luis J V
authors.initials: LJ
authors.lastname: Galietta
authors.forename: Olga
authors.initials: O
authors.lastname: Zegarra-Moran
mesh_terms: D001826:Body Fluids / Q000187:drug effects / Q000378:metabolism; D001980:Bronchi / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D002478:Cells, Cultured; D016207:Cytokines / Q000494:pharmacology*; D015536:Down-Regulation / Q000187:drug effects; D015180:Electrophoresis, Gel, Two-Dimensional; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D018836:Inflammation Mediators / Q000494:pharmacology*; D011506:Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D040901:Proteomics; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D016207:Cytokines; D018836:Inflammation Mediators; D011506:Proteins