title: Regulation of CXCR/IL-8 in human airway epithelial cells.
abstract: BACKGROUND
  Severe asthma is characterized by neutrophilic inflammation and high levels of interleukin (IL)-8. Airway epithelial cells play a pivotal role in the pathogenesis and chronicity of asthma. The objective of this work was to determine whether CXC receptors were involved in human small airway epithelial cell (SAEC) activity by incubating them with IL-8; the investigation also included a proteomic approach.
  
  
  METHODS
  IL-6 and intercellular adhesion molecule-1 (ICAM-1) were assessed by ELISA and flow cytometry, respectively. CXCR-1 and CXCR-2 receptor mRNA and protein expressions were analyzed by RT-PCR, immunocytochemistry and flow cytometry. Cells were incubated with different concentrations (0-100 ng/ml) of IL-8. The involvement of both receptors was assessed using specific antibodies.
  
  
  RESULTS
  Only the CXCR-1 receptor was expressed in SAECs. IL-8 (50 ng/ml, 12 h) induced the release of IL-6 and had no effect on ICAM-1. Supernatants analyzed by surface enhanced laser desorption ionization time of flight mass spectrometry (SELDI-TOF MS) showed very weak differences in peptide profiles. Interestingly, 4,820-m/z peptide release was detected in the presence of IL-8 and abolished by CXCR-1 antibody.
  
  
  CONCLUSIONS
  The present study illustrated the fact that IL-8 mediated by CXCR-1 increased IL-6. We also highlight the usefulness of SELDI ProteinChip technology to confirm the potential variation of peptide profile. Moreover, we were able to detect the 4,820-m/z peptide secreted in vitro by human airway epithelial cells induced by IL-8 via CXCR-1 receptor. Determination of the protein secretion profile in response to inflammatory stimuli could be an important therapeutic strategy in severe asthma.
authors.affiliation: Clinique des Maladies Respiratoires, CHU-Montpellier, Montpellier, France.
authors.forename: Delphine
authors.initials: D
authors.lastname: Gras
authors.forename: Laurent
authors.initials: L
authors.lastname: Tiers
authors.forename: Isabelle
authors.initials: I
authors.lastname: Vachier
authors.forename: Laure Denis
authors.initials: LD
authors.lastname: de Senneville
authors.forename: Arnaud
authors.initials: A
authors.lastname: Bourdin
authors.forename: Philippe
authors.initials: P
authors.lastname: Godard
authors.forename: Sylvain
authors.initials: S
authors.lastname: Lehman
authors.forename: Pascal
authors.initials: P
authors.lastname: Chanez
mesh_terms: D000906:Antibodies / Q000276:immunology / Q000494:pharmacology; D001980:Bronchi / Q000166:cytology / Q000378:metabolism; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D015870:Gene Expression / Q000235:genetics; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D016209:Interleukin-8 / Q000378:metabolism* / Q000494:pharmacology; D008168:Lung / Q000166:cytology*; D010455:Peptides / Q000032:analysis / Q000378:metabolism; D011506:Proteins / Q000032:analysis / Q000378:metabolism; D054387:Receptors, CXCR / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D023062:Receptors, Interleukin-8A / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D023063:Receptors, Interleukin-8B / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D020545:Respiratory Mucosa / Q000166:cytology / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D000906:Antibodies; D015850:Interleukin-6; D016209:Interleukin-8; D010455:Peptides; D011506:Proteins; D054387:Receptors, CXCR; D023062:Receptors, Interleukin-8A; D023063:Receptors, Interleukin-8B; D018799:Intercellular Adhesion Molecule-1