title: Stent-induced tracheal stenosis can be predicted by IL-8 expression in rabbits.
abstract: BACKGROUND
  Bare metal stents may cause complications like fibrous encapsulation, granulation and tracheal stenosis. We investigated the behaviour of three commercially available stents in vivo (rabbits) and in vitro (coculture of those stents with epithelial and fibroblast cell lines). Also, we investigated whether development of tracheal stenosis could be predicted by any biological marker.
  
  
  METHODS
  The tracheae of 30 rabbits were implanted with either nitinol stents, with or without paclitaxel elution, or a cobalt-based stent. An additional ten rabbits underwent mock implantation (controls). Serial peripheral venous blood samples were taken throughout the study, and several cytokines measured. Animals were euthanized on day 90, with immediate tracheal endoscopy and lavage performed, then necropsy.
  
  
  RESULTS
  Rabbits with cobalt-based stent exhibited more inflammation and the highest stenosis incidence, with reduced survival. Both in vivo and in vitro, this stent induced higher IL-8 levels than nitinol stents. Most important, the presence of stent-induced tracheal stenosis was closely associated to increase in IL-8 expression in blood just 1 day after tracheal stent implantation: a 1·19-fold increase vs. baseline had 83% sensitivity, 83% specificity, 77% positive predictive value, 88% negative predictive value and 83% accuracy to predict development of stenosis.
  
  
  CONCLUSIONS
  The cobalt-based stent had the highest incidence of tracheal inflammation and stenosis. On the other hand, the paclitaxel-eluting nitinol stent did not prevent those complications and provoked a marked reaction compared with the bare nitinol stent. Early increase in IL-8 expression in blood after stent implantation could predict development of tracheal stenosis in rabbits.
authors.affiliation: Unidad Médico-Quirúrgica de Enfermedades Respiratorias, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/Universidad de Sevilla, Seville, Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: Arellano-Orden
authors.affiliation: Minimally Invasive Techniques Research Group (GITMI), University of Zaragoza, Zaragoza, Spain.
authors.forename: Carolina
authors.initials: C
authors.lastname: Serrano
authors.affiliation: Unidad Médico-Quirúrgica de Enfermedades Respiratorias, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/Universidad de Sevilla, Seville, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Montes-Worboys
authors.affiliation: Unidad Médico-Quirúrgica de Enfermedades Respiratorias, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/Universidad de Sevilla, Seville, Spain.
authors.forename: Verónica
authors.initials: V
authors.lastname: Sánchez-López
authors.affiliation: Minimally Invasive Techniques Research Group (GITMI), University of Zaragoza, Zaragoza, Spain.
authors.forename: Alicia
authors.initials: A
authors.lastname: Laborda
authors.affiliation: Minimally Invasive Techniques Research Group (GITMI), University of Zaragoza, Zaragoza, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Lostalé
authors.affiliation: Minimally Invasive Techniques Research Group (GITMI), University of Zaragoza, Zaragoza, Spain.
authors.forename: Celia
authors.initials: C
authors.lastname: Lahuerta
authors.affiliation: Unidad Médico-Quirúrgica de Enfermedades Respiratorias, Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/Universidad de Sevilla, Seville, Spain.|CIBER de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Rodríguez-Panadero
authors.affiliation: Minimally Invasive Techniques Research Group (GITMI), University of Zaragoza, Zaragoza, Spain.|Interventional Radiology, Hospital Clinico Universitario, University of Zaragoza, Zaragoza, Spain.|CIBER Bioengineering, Biomaterials and Nanomedicine (BBB), Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: Miguel Ángel
authors.initials: MÁ
authors.lastname: de Gregorio
mesh_terms: D000497:Alloys; D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage; D002460:Cell Line; D054855:Drug-Eluting Stents / Q000009:adverse effects; D004847:Epithelial Cells / Q000378:metabolism; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D016209:Interleukin-8 / Q000276:immunology* / Q000378:metabolism; D053208:Kaplan-Meier Estimate; D017239:Paclitaxel / Q000008:administration & dosage; D011474:Prosthesis Design; D011817:Rabbits; D012137:Respiratory System / Q000166:cytology; D015607:Stents / Q000009:adverse effects*; D014135:Tracheal Stenosis / Q000209:etiology / Q000276:immunology*; D014805:Vitamin B 12
chemical_list: D000497:Alloys; D000970:Antineoplastic Agents; D016209:Interleukin-8; C013616:nitinol; D014805:Vitamin B 12; D017239:Paclitaxel
keywords: Cytokine; fibrosis; rabbits; stents; tracheal stenosis