title: Collagen cell carriers seeded with human urothelial cells for urethral reconstructive surgery: first results in a xenograft minipig model.
abstract: OBJECTIVE
  Urethral strictures are a common disease of the lower urinary tract in men. At present, the use of buccal mucosa is the method of choice for long or recurrent strictures. However, autologous tissue-engineered grafts are still under investigation for reconstructive urological surgery. The aim of this pilot study was to evaluate the use of human urothelial cells (HUC) seeded on bovine collagen type I-based cell carriers (CCC) in an animal model and to evaluate short-term outcome of the surgical procedure.
  
  
  METHODS
  Four male Göttingen minipigs were used with immunosuppression (cyclosporine A) for this pilot xenograft study. HUC obtained from human benign ureteral tissue were stained by PKH26 and seeded on a collagen cell carrier (CCC). Seven weeks after urethral stricture induction and protective vesicostomy, cell-seeded CCC was implanted in the urethra with HUC luminal and antiluminal, respectively. After two weeks animals were euthanized, urethrography and histological assessment were performed.
  
  
  RESULTS
  Surgery was technically feasible in all minipigs. Stricture was radiologically established 7 weeks after induction. CCC was visible after two weeks and showed good integration without signs of inflammation or rejection. In the final urethrography, no remaining stricture could be detected. Near porcine urothelium, PKH26-positive areas were found even if partially detached from CCC. Although diminished, immunofluorescence with pankeratin, CK20, E-cadherin and ZO-1 showed intact urothelium in several areas on and nearby CCC.
  
  
  CONCLUSIONS
  Finally, this study demonstrates that the HUC-seeded CCC used as a xenograft in minipigs is technically feasible and shows promising results for further studies.
authors: Department of Urology, Eberhard Karls University Tuebingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany.
authors: Stefan
authors: S
authors: Aufderklamm
authors: Experimental and Clinical Research Center (ECRC), University Clinic Charité, Berlin, Germany.
authors: Martin
authors: M
authors: Vaegler
authors: Department of Urology, Eberhard Karls University Tuebingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany.
authors: Alexandra
authors: A
authors: Kelp
authors: Department of Urology, Eberhard Karls University Tuebingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany.
authors: Sabine
authors: S
authors: Maurer
authors: Department of Urology, Eberhard Karls University Tuebingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany.
authors: Leon
authors: L
authors: Gustafsson
authors: Department of Urology, Diakonie Hospital Stuttgart, Stuttgart, Germany.
authors: Jens
authors: J
authors: Mundhenk
authors: Viscofan, BioEngineering, Weinheim, Germany.
authors: Silke
authors: S
authors: Busch
authors: Animal Doctor Facility, Neustadt/Aisch, Germany.
authors: Lisa
authors: L
authors: Daum
authors: Department of Urology, Eberhard Karls University Tuebingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany.
authors: Arnulf
authors: A
authors: Stenzl
authors: Department of Urology, Eberhard Karls University Tuebingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany. bastian.amend@med.uni-tuebingen.de.
authors: Bastian
authors: B
authors: Amend
authors: Department of Urology, Eberhard Karls University Tuebingen, Hoppe-Seyler-Str. 3, 72076, Tübingen, Germany.
authors: Karl-Dietrich
authors: KD
authors: Sievert
mesh_terms: D000818:Animals; D002417:Cattle; D017690:Cell Transplantation / Q000379:methods*; D024042:Collagen Type I / Q000502:physiology; D004195:Disease Models, Animal; D064593:Heterografts; D006801:Humans; D008297:Male; D008953:Models, Anatomic; D019651:Plastic Surgery Procedures / Q000379:methods*; D013552:Swine; D013556:Swine, Miniature; D023822:Tissue Engineering / Q000379:methods*; D016896:Treatment Outcome; D014525:Urethral Stricture / Q000601:surgery*; D013521:Urologic Surgical Procedures, Male / Q000379:methods*; D019459:Urothelium / Q000166:cytology*
chemical_list: D024042:Collagen Type I
keywords: Collagen matrix; Human urothelial cells; Reconstructive urology; Tissue engineering; Urethra; Xenograft