title: Tracheal regeneration following tracheal replacement with an allogenic aorta.
abstract: BACKGROUND
  Tracheal replacement remains an unsolved surgical problem. Attempts to use tracheal substitutes have failed to achieve reliable results. In this study, tracheal regeneration was obtained after tracheal replacement with an allogenic aorta.
  
  
  METHODS
  Twenty female sheep underwent a 8-cm tracheal replacement with a fresh aortic allograft. In the six last animals, aortic grafts came from male sheep. A stent prevented airway collapse. No immunosuppressive therapy was used. Aortic segments were retrieved at regular intervals up to 16 months. A polymerase chain reaction for the SRY gene was performed in specimens with aortic grafts from male sheep.
  
  
  RESULTS
  All animals but one survived the operation without complications. Clearly identified between the suture lines, the aortic segments were completely transformed into a tracheal structure. Histology showed initially an inflammatory reaction with proliferation of a squamous epithelium followed by mucociliary epithelium and newly formed cartilage rings. SRY gene was not found in newly formed cartilage rings showing that the regeneration originated from recipient cells.
  
  
  CONCLUSIONS
  This study presents a new type of tissue regeneration and brings hopes to the treatment of extensive tracheal lesions.
authors.affiliation: Laboratoire d'Etude des Greffes et Prothèses Cardiaques, Hôpital Broussais, Université Paris 6, Paris, France. emartinod@wanadoo.fr
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Martinod
authors.forename: Agathe
authors.initials: A
authors.lastname: Seguin
authors.forename: Muriel
authors.initials: M
authors.lastname: Holder-Espinasse
authors.forename: Marianne
authors.initials: M
authors.lastname: Kambouchner
authors.forename: Martine
authors.initials: M
authors.lastname: Duterque-Coquillaud
authors.forename: Jacques F
authors.initials: JF
authors.lastname: Azorin
authors.forename: Alain F
authors.initials: AF
authors.lastname: Carpentier
mesh_terms: D000818:Animals; D001011:Aorta / Q000637:transplantation*; D005260:Female; D008297:Male; D012038:Regeneration; D012756:Sheep; D013997:Time Factors; D014132:Trachea / Q000473:pathology / Q000502:physiology* / Q000637:transplantation*