From the intestinal neobladder to the bioartificial bladder: remarks on some biological implications

In an attempt to avoid the complications associated with use of bowel for bladder augmentation or replacement (systemic metabolic imbalances, malignancy, etc.), various solutions have been proposed for an artificial orthotopic neobladder: total alloplastic prosthetic bladder in nonbiological material (silicon rubber, polyurethane, etc.); tissue-engineered bladder by the patient's own urothelial--and smooth muscle--cells obtained by biopsy of a urinary segment with less neoplastic potential and cultured in vitro, then seeded onto biodegradable bladder-shaped scaffold, autografted in the original host; bladder augmentation or replacement using acellular matrix derived from small-intestinal submucosa or from bladder or ureter as a scaffold structure for the subsequent regrowth of functional organ. Tissue-engineering technology with autologous native cells is being undertaken for every type of organ within the urinary tract. At the present moment, other roads are less practicable, e.g. to obtain "spare bladders" from human therapeutic cloning or from transgenic-humanized animals.