title: Tracheal replacement with cryopreserved, decellularized, or glutaraldehyde-treated aortic allografts.
abstract: BACKGROUND
  Seven years of experimental research provided a valuable tracheal substitute, the aortic allograft, which can promote the regeneration of epithelium and cartilage. In human application, both fresh and preserved aortic allografts could be used. The optimal method of aortic allograft preservation remains to be evaluated. This study assessed the use of cryopreserved, decellularized, or glutaraldehyde-treated aortic allografts as tracheal substitutes.
  
  
  METHODS
  Twenty-two sheep underwent tracheal replacement using cryopreserved (n = 10), decellularized (n = 7) or glutaraldehyde-treated (n = 5) allografts, supported by a temporary stent to prevent airway collapse. Aortic segments were retrieved at regular intervals up to 12 months after implantation to analyze the regenerative process.
  
  
  RESULTS
  All animals survived the operation. Major complications such as infection, stent migration, or obstruction were predominantly encountered in the decellularized group. The lack of major inflammatory response within the aortic graft observed in the glutaraldehyde group was associated with the absence of tracheal regeneration. Histologic examinations showed a progressive transformation of the aorta into a tracheal tissue comprising respiratory epithelium and cartilage only in the cryopreserved group.
  
  
  CONCLUSIONS
  This study demonstrated that regeneration of a functional tissue could be obtained after tracheal replacement with a cryopreserved aortic allograft. The regenerative process followed the same pattern as previously described for fresh allografts. Cryopreserved aortic allografts present major advantages: availability in tissue banks, permanent storage, and no need for immunosuppression. This offers a new field of perspectives for clinical application in patients with extensive tracheal cancer.
authors.affiliation: Laboratoire de Recherches Biochirurgicales, Fondation Alain Carpentier, Université Paris V, Paris, France. agathe.seguin@avc.aphp.fr
authors.forename: Agathe
authors.initials: A
authors.lastname: Seguin
authors.forename: Dana
authors.initials: D
authors.lastname: Radu
authors.forename: Muriel
authors.initials: M
authors.lastname: Holder-Espinasse
authors.forename: Patrick
authors.initials: P
authors.lastname: Bruneval
authors.forename: Anne
authors.initials: A
authors.lastname: Fialaire-Legendre
authors.forename: Martine
authors.initials: M
authors.lastname: Duterque-Coquillaud
authors.forename: Alain
authors.initials: A
authors.lastname: Carpentier
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Martinod
mesh_terms: D000818:Animals; D001013:Aorta, Thoracic / Q000166:cytology / Q000637:transplantation*; D015925:Cryopreservation; D005976:Glutaral; D012756:Sheep; D014021:Tissue Preservation / Q000379:methods; D014132:Trachea / Q000601:surgery*
chemical_list: D005976:Glutaral