Bladder augmentation using allogenic bladder submucosa seeded with cells.

OBJECTIVES The search for a suitable material to reconstruct the genitourinary tract has been a challenging task. Bowel has been widely used for urinary tract reconstruction, despite its subsequent complications. We investigated the possibility of using allogenic bladder submucosa, a tissue consisting of nonimmunogenic acellular collagen, either with or without cells, as a material for bladder augmentation. METHODS Partial cystectomies were performed in 10 beagle dogs. Both urothelial and smooth muscle cells were harvested and expanded separately in 5 animals. The allogenic bladder submucosa obtained from sacrificed dogs was seeded with muscle cells on one side and urothelial cells on the opposite side. All beagles underwent cruciate cystotomies on the bladder dome. Augmentation cystoplasty was performed with the allogenic bladder submucosa seeded with cells in 5 animals and with the allogenic bladder submucosa without cells in 5. The augmented bladders were retrieved 2 and 3 months after augmentation. RESULTS Bladders augmented with the allogenic bladder submucosa seeded with cells showed a 99% increase in capacity compared with bladders augmented with the cell-free allogenic bladder submucosa, which showed only a 30% increase in capacity. All dogs showed a normal bladder compliance, as evidenced by urodynamic studies. Histologically, all retrieved bladders contained a normal cellular organization consisting of a urothelial lined lumen surrounded by submucosal tissue and smooth muscle. Immunocytochemical analyses confirmed the urothelial and muscle cell phenotype and showed the presence of nerve fibers. CONCLUSIONS These results show that allogenic bladder submucosa seeded with cells appears to be an excellent option as a biomaterial for bladder augmentation.