title: [Minimizing the antigenicity of tracheal allografts by using a technique of cryopreservation].
abstract: OBJECTIVE
  To investigate the proper time of cryo-preserving tracheal allograft so as to minimize its antigenicity.
  
  
  METHODS
  On a dog model, this study was carried out by allografting a tracheal into a muscular flap formed with sternocephalic muscle and sternohyoid--sternothyroid muscle. The tracheal was treated with cryopreservation in defferent intervals. The viability of the graft was evaluated by the examination of fiberoptic bronchoscopy, histopathology and microangiography. The blood flow of the tracheal mucous was measured with a blood flowmeter and the survival area was decided in the calculation of the percentage.
  
  
  RESULTS
  There are no significant differences in the mucous membrane appearance and the mucosal blood flow one week after the surgery among the non-cryopreservation group and the groups treated with cryopreservation in 1 day, 2 weeks, 4 weeks, 6 weeks and 8 weeks. The graft was found to start necrosis 2 weeks after the transplantation with the infiltration of mononuclear cells examined under light microscope in almost all of the groups, especially in the non-cryopreservation group and the groups treated with cryopreservation in 1 day, 2 weeks. However, there was no significant difference among the autograft group and the allograft groups cryopreservated in 6 weeks and 8 weeks, and the infiltration of the mononuclear cells was not found in these groups either.
  
  
  CONCLUSIONS
  The antigenicity of the tracheal allografts could be significantly decreased by the treatment of cryopreservation over 6 weeks.
authors.affiliation: Plastic Surgery Hospital, Chinese Academy of Medical Science, Beijing 100041, China.
authors.forename: Lian-Zhao
authors.initials: LZ
authors.lastname: Wang
authors.forename: Gang
authors.initials: G
authors.lastname: Zhou
authors.forename: Fei
authors.initials: F
authors.lastname: Fan
authors.forename: Feng
authors.initials: F
authors.lastname: Zhang
authors.forename: Fu-Shan
authors.initials: FS
authors.lastname: Xue
authors.forename: Jie
authors.initials: J
authors.lastname: Luan
authors.forename: Guo-Bin
authors.initials: GB
authors.lastname: Cai
authors.forename: Fan-Hui
authors.initials: FH
authors.lastname: Meng
authors.forename: Pei-Tao
authors.initials: PT
authors.lastname: Wang
authors.forename: Hua-Bing
authors.initials: HB
authors.lastname: Wang
mesh_terms: D000818:Animals; D020680:Bronchoscopes; D015925:Cryopreservation / Q000379:methods*; D004285:Dogs; D045268:Flowmeters; D023421:Models, Animal; D020545:Respiratory Mucosa / Q000098:blood supply / Q000473:pathology; D014132:Trachea / Q000276:immunology* / Q000473:pathology / Q000637:transplantation*; D014184:Transplantation, Homologous