Bladder Progenitor Cells and Their Use for Tissue Engineering

Gastrointestinal segments are commonly used as tissues for bladder replacement or repair. These include matrices for tissue regeneration and tissue engineering using cell transplantation. Engineering tissue using selective cell transplantation provides the means to create functional, new bladder segments. Tissue engineering technologies have already been clinically applied to the bladder by using injectable cells for the treatment of vesicoureteral reflux and urinary incontinence. The approach, followed to bioengineer bladder tissue, involves the eventual use of autologous cells, thus avoiding rejection: A biopsy of tissue is obtained from the host, and the cells are dissociated and expanded in vitro, reattached to a matrix, and implanted into the same host. The success of using cell transplantation strategies for bladder reconstruction depends on the ability to use donor tissue efficiently and to provide the right conditions for longterm survival, differentiation, and growth. The supporting matrix is composed of biodegradable artificial or natural polymers that can allow cell survival by diffusion of nutrients across short distances once the cell support matrix is implanted.