Urothelial cell transplantation using biodegradable synthetic scaffolds

Reconstruction of the urinary bladder with bowel to restore storage capacit y is associated with significant complications arising from substituting an absorptive, mucus-producing intestinal epithelium for the barrier urotheli um of the bladder. To overcome these problems, we are developing a "composi te enterocystoplasty" procedure to replace the epithelium of the bowel with autologous in vitro-propagated normal urothelial cells. The aims of this s tudy were to evaluate synthetic biomaterials as delivery vehicles for the c ultured urothelial cells and provide support during transfer and cell adher ence to the de-epithelialized bowel wall. The surgical compliance of 12 bio materials was evaluated, along with their ability to support urothelial cel l attachment. Transfer of urothelial cells onto biomaterials as single cell suspensions or intact cell sheets was investigated. Seeding of a single ce ll suspension on to non-woven mesh resulted in poor cell attachment. Seedin g onto woven mesh was more efficient, but the most effective transfer metho d involved producing an intact cell sheet that could be combined with woven , knitted and non-woven biomaterials. Transfer of the cell sheet : mesh com plexes onto a de-epithelialized bladder stroma produced a stratified epithe lium incorporating the strands of the mesh and expressing urothelial-associ ated antigens after 48 h in organ culture. Thus, we have developed and eval uated a suitable transfer method for in vitro propagated urothelial cells t o be used in "composite enterocystoplasty". (C) 2001 Kluwer Academic Publis hers.