We conducted this study to evaluate the combined effect of acellular bladder submucosa matrix (BSM) and autologous urethral tissue for the treatment of long segment urethral stricture in a rabbit model. To prepare the BSM, porcine bladder submucosa was processed, decellularized, configured into a sheet-like shape, and sterilized. Twenty rabbits were randomized to normal control, urethral stricture, urethroplasty using BSM only or BSM/autologous urethral tissue (n=5 per group). Retrograde urethrography was performed at 4, 8, and 12 weeks postoperatively, and the grafted specimens were harvested at week 12 to evaluate urethral reconstruction through histopathologic and immunohistochemical analysis. The mean urethral width of the control, stricture, BSM, and BSM/autologous urethral tissue groups at week 12 was 10.3+/-0.80, 3.8+/-1.35, 8.8+/-0.84, and 9.1+/-1.14 mm, respectively. The histopathologic study revealed that the BSM/autologous urethral tissue graft had a normal area of urethral lumen, compact muscular layers, complete epithelialization, and progressive infiltration by vessels in the regenerated urethra. In contrast, the BSM grafts revealed keratinized epithelium, abundant collagenized fibrous connective tissue, and were devoid of bundles of circular smooth muscle. Nontransected ventral onlay-augmented urethroplasty using an acellular BSM scaffold combined with an autologous urethral tissue graft represents a feasible procedure for urethral reconstruction.
Animals ; Epithelium/surgery ; Mucous Membrane/cytology/*transplantation ; Muscle, Smooth/surgery ; Rabbits ; Reconstructive Surgical Procedures/methods ; Swine ; Tissue Engineering ; Urethra/*surgery ; Urethral Stricture/*surgery ; Urinary Bladder/*cytology

We conducted this study to evaluate the combined effect of acellular bladder submucosa matrix (BSM) and autologous urethral tissue for the treatment of long segment urethral stricture in a rabbit model. To prepare the BSM, porcine bladder submucosa was processed, decellularized, configured into a sheet-like shape, and sterilized. Twenty rabbits were randomized to normal control, urethral stricture, urethroplasty using BSM only or BSM/autologous urethral tissue (n=5 per group). Retrograde urethrography was performed at 4, 8, and 12 weeks postoperatively, and the grafted specimens were harvested at week 12 to evaluate urethral reconstruction through histopathologic and immunohistochemical analysis. The mean urethral width of the control, stricture, BSM, and BSM/autologous urethral tissue groups at week 12 was 10.3+/-0.80, 3.8+/-1.35, 8.8+/-0.84, and 9.1+/-1.14 mm, respectively. The histopathologic study revealed that the BSM/autologous urethral tissue graft had a normal area of urethral lumen, compact muscular layers, complete epithelialization, and progressive infiltration by vessels in the regenerated urethra. In contrast, the BSM grafts revealed keratinized epithelium, abundant collagenized fibrous connective tissue, and were devoid of bundles of circular smooth muscle. Nontransected ventral onlay-augmented urethroplasty using an acellular BSM scaffold combined with an autologous urethral tissue graft represents a feasible procedure for urethral reconstruction.
Animals ; Epithelium/surgery ; Mucous Membrane/cytology/*transplantation ; Muscle, Smooth/surgery ; Rabbits ; Reconstructive Surgical Procedures/methods ; Swine ; Tissue Engineering ; Urethra/*surgery ; Urethral Stricture/*surgery ; Urinary Bladder/*cytology

AIMTo investigate the transformation of characteristics of epidermal cells from foreskin which were used to reconstruct male rabbit anterior urethra in combination with acellular collagen matrices.

METHODSIn three rabbits, autologous foreskin epidermal cells were isolated, expanded in vitro, and seeded (inoculated) onto a tubular acellular collagen matrix, acquired from allogeneic rabbit bladder submucosa. A urethral mucosal defect was created, and urethral reconstruction was performed with the tubular acellular collagen matrix seeded with epidermal cells.

RESULTSOn gross examination at 12 months following the procedure, the mucosa of the urethral grafts appeared lubricous and smooth. Urethrography showed that a wide urethral caliber had been maintained without any sign of strictures. Histological examination showed a transitional cell layer in the graft without evidence of a margin between the graft and the host tissue at 12 months postoperatively.

CONCLUSIONEpidermal cells seeded onto acellular collagen matrices can be successfully used to reconstruct urethras that have defects and are transformed to transitional epithelial cells.

Animals ; Cell Transplantation ; methods ; Collagen ; Epidermis ; cytology ; Foreskin ; cytology ; Graft Survival ; Male ; Mucous Membrane ; cytology ; Rabbits ; Reconstructive Surgical Procedures ; methods ; Tissue Culture Techniques ; Tissue Engineering ; methods ; Urethra ; surgery ; Urethral Stricture ; surgery