Success with Replacement Bladders
Findings from an animal study show than an entire urinary bladder can be regenerated in six months
To grow a replacement bladder, bladder progenitor cells are obtained, grown in culture, and seeded on a biodegradable bladder-shaped scaffold made from collagen and/or polyglycolic acid. The neo-organ is then implanted into the subject.
In a six-month study of 23 canines, researchers found that a “neo-bladder replacement construct” could regenerate the entire urinary bladder within six months after implantation. At around two months after implantation, the bladder wall structure consisted of urothelium, muscle, and serosa. At six months, the regenerated bladder showed near-baseline capacity and cystographic findings, and the bladder wall showed near native pharmacologic and electrophysiologic functional responses.
So far, researchers have found no abnormal tissue development, immune response, or evidence of systemic response to the neo-bladder regeneration. Human trials are underway.
“This treatment option essentially regenerates the patient's own bladder, reducing the risk of rejection and the need for immunosuppressant drugs,” said Timothy Bertram, DVM, PhD, senior vice-president of Tengion Inc., of
Tengion is conducting three Phase II clinical trials of its neo-bladder technology at leading academic medical centers across the
“What we are doing in the clinical trials right now is looking at augmentation. What that means is that instead of regenerating the entire bladder we are regenerating a majority of the bladder which is physiologically active in urine storage,” Dr. Bertram said.
Patients with advanced bladder disease often require cystectomy, and replacement bladders made from intestinal tissue have been used successfully. These types of replacement bladders, however, have also been associated with many well documented complications, such as chronic urinary retention, hematuria, and infection.