title: Tracheal allotransplantation in beagle dogs without immunosuppressants.
abstract: BACKGROUND
  The antigenicity of tracheal grafts is still unclear. We investigated the possibility of performing tracheal allotransplantation without immunosuppressants.
  
  
  METHODS
  Intrathoracic five-ring tracheal replacements were performed in beagle dogs without immunosuppressants (n = 18). The dogs were divided into 9 pairs, and grafts were exchanged within the pairs. In group 1 (n = 6), the paired dogs were blood relatives, whereas in group 2 (n = 12), the paired dogs were not related. Full-thickness skin transplantation was also performed in both groups.
  
  
  RESULTS
  In group 1, 5 animals survived uneventfully for more than 3 months. No stenosis was observed in any of the dogs. In group 2, the grafts were incorporated by the host trachea in 2 dogs. Four animals died of airway obstruction within 3 months. Moderate or slight airway stenosis was observed in 6 dogs. Rejection was confirmed by histologic examination. In both groups, all of the skin allografts were destroyed within 2 weeks.
  
  
  CONCLUSIONS
  After tracheal allotransplantation, long-term survival was achieved, especially in recipient dogs that were blood relatives of donors. We conclude that it is possible to perform tracheal allotransplantation using histocompatible matched grafts without immunosuppressants.
authors.affiliation: Department of Bioartificial Organs, Institute for Frontier Medical Sciences, Kyoto University, Japan. lyu@frontier.kyoto-u.ac.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Liu
authors.forename: T
authors.initials: T
authors.lastname: Nakamura
authors.forename: Y
authors.initials: Y
authors.lastname: Shimizu
authors.forename: H
authors.initials: H
authors.lastname: Ueda
authors.forename: M
authors.initials: M
authors.lastname: Yoshitani
authors.forename: T
authors.initials: T
authors.lastname: Toba
authors.forename: S
authors.initials: S
authors.lastname: Fukuda
mesh_terms: D000818:Animals; D004285:Dogs; D006084:Graft Rejection / Q000276:immunology / Q000473:pathology*; D006650:Histocompatibility Testing; D007165:Immunosuppression Therapy; D016038:Skin Transplantation / Q000276:immunology / Q000473:pathology; D014132:Trachea / Q000276:immunology / Q000473:pathology / Q000637:transplantation*; D023001:Transplantation Tolerance / Q000276:immunology; D014184:Transplantation, Homologous