Tissue-engineered tubular graft for urinary diversion after radical cystectomy in rabbits

Clinically, using ileal conduit for urinary diversion often caused many serious complications. Tissue engineering technology may offer an alternative method for urinary diversion after radical cystectomy. In this study, we aimed to make a tissue-engineered tubular graft (TETG) using bladder epithelial cells and bladder acellular matrix (BAM) for urinary diversion in rabbits.

Bladder epithelial cells of rabbit were cultivated and expanded in vitro, which were then seeded on BAM and cultured for 7 d. Then, cell-seeded grafts of 4 cm length and 0.8 cm diameter were used to make TETGs and transferred into the omentum for 2 wk before urinary diversion. In the experimental group, bladders of the rabbits were removed. The proximal ends of TETGs were anastomosed with ureters, and the distal ends were anastomosed with the abdominal stomas. In the control group, TETGs were constructed using unseeded BAM. Newly formed tissue structures were functionally and microscopically evaluated using urography and immunohistochemistry at 1, 2, 4, and 8 wk after operation, respectively. Histologic examination with hematoxylin and eosin staining was conducted to assess tissue regeneration. Immunohistochemistry was performed with AE1/AE3, uroplakin Ⅲa, and zonula occludens 1 (ZO-1) antibodies.

All animals were alive in the experimental group. Hematoxylin and eosin staining showed epithelial coverage in TETG. Immunohistochemistry showed positive stain with AE1/AE3, uroplakin Ⅲa, and ZO-1, which indicated mature and functional epithelial cells on the lumen of TETG. Intravenous urography showed that there were no obstructions in TETGs. In the control group, four rabbits were dead within 2 wk, and scar formation, atresia, and severe hydronephrosis were found.

It was feasible that TETG constructed using bladder epithelial cells and BAM for urinary diversion after radical cystectomy in rabbits.