icnmgrjill
04-29-2006, 10:56 AM
Artificial Bladders Become A Reality – Sort of!
Creating New Bladder Tissue In Just Seven Weeks
(ICN Staff - April 29, 2006)
This months issue of The Lancet provided great hope for patients struggling with severe, end stage bladder disease. Researchers Anthony Atala and colleagues revealed the successful implantation and long term viability bioengineered bladder tissue that had been implanted in seven young patients. The results (of up to four years) have been excellent.
“Tissue-engineering” is a new field of medicine in which a patients own tissue is re-grown and then inserted back into their bodies, thus dramatically reducing potential complications and/or tissue rejection. The question, of course, is how could you create an artificial bladder that maintains all of the important qualities of a real bladder, including its ability to expand as urine fills it, to mimic the three essential layers of the bladder (the urothelium, the submucoas and the muscle) and to provide an adequate blood supply to keep the tissues healthy. Their technique is innovative and may just inspire more people to join in efforts to create artificial organs.
Dr. Atala’s research focused on patients with end stage bladder disease as a result of spina bifida. Each patient underwent a bladder biopsy during which both muscle and urothelial cells were removed from the dome of the bladder. These were then cultured and grown into large colonies of tissue.
A separate scaffold, shaped much like a bowl, was constructed using either the patients own bladder submucosa (also cultured) or from a biodegradable combination of collagen and PGA, a mesh like material used to repair hernias. To recreate the three layers of the bladder, the inside of the bowl was seeded with urothelial cells and the outside of the bowl was seeded with muscle cells.
The problem, though, is blood supply. How will this tissue thrive without a source of blood and vital oxygen (aka blood vessels)? The answer, again, lies in the human body with an organ you probably haven’t heard of called the omentum. The omentum is part of the peritoneum and is very rich in blood vessels and lympathic tissue. In many surgical procedures, it can be wrapped around the intestine or bladder to help facilitate healing.
Just 7- 8 weeks after biopsy, the researchers implanted the new tissue onto the patients existing bladder. Please note that this was not a bladder transplant nor was the bladder replaced entirely. It was an augmentation that expanded the capacity of the bladder.
The results are encouraging. The researchers found that the engineered bladders continued to develop and appeared normal both anatomically and functionally. There was no evidence of abnormal changes in the tissue. Patients tolerated the surgical procedure well, with hospital stays varying from 23 to 34 days.
Patients were followed for up to 61 months post surgery. Each patient showed an increase in bladder capacity and an improvement in urinary frequency. Upon microscopic examination, the boundary between the original vs. new bladder segments were indistinguishable. Biopsies showed the tri-layered structure with all expected components. This is an amazing breakthrough for bladder repair.
While this has not been applied, as yet, to IC patients, it is a source of great hope. Not only have been able to create new bladder tissue, they may soon be able to create entire organs, such as kidneys for transplant patients. You have to admit that the science is amazing!
Jill O.
Creating New Bladder Tissue In Just Seven Weeks
(ICN Staff - April 29, 2006)
This months issue of The Lancet provided great hope for patients struggling with severe, end stage bladder disease. Researchers Anthony Atala and colleagues revealed the successful implantation and long term viability bioengineered bladder tissue that had been implanted in seven young patients. The results (of up to four years) have been excellent.
“Tissue-engineering” is a new field of medicine in which a patients own tissue is re-grown and then inserted back into their bodies, thus dramatically reducing potential complications and/or tissue rejection. The question, of course, is how could you create an artificial bladder that maintains all of the important qualities of a real bladder, including its ability to expand as urine fills it, to mimic the three essential layers of the bladder (the urothelium, the submucoas and the muscle) and to provide an adequate blood supply to keep the tissues healthy. Their technique is innovative and may just inspire more people to join in efforts to create artificial organs.
Dr. Atala’s research focused on patients with end stage bladder disease as a result of spina bifida. Each patient underwent a bladder biopsy during which both muscle and urothelial cells were removed from the dome of the bladder. These were then cultured and grown into large colonies of tissue.
A separate scaffold, shaped much like a bowl, was constructed using either the patients own bladder submucosa (also cultured) or from a biodegradable combination of collagen and PGA, a mesh like material used to repair hernias. To recreate the three layers of the bladder, the inside of the bowl was seeded with urothelial cells and the outside of the bowl was seeded with muscle cells.
The problem, though, is blood supply. How will this tissue thrive without a source of blood and vital oxygen (aka blood vessels)? The answer, again, lies in the human body with an organ you probably haven’t heard of called the omentum. The omentum is part of the peritoneum and is very rich in blood vessels and lympathic tissue. In many surgical procedures, it can be wrapped around the intestine or bladder to help facilitate healing.
Just 7- 8 weeks after biopsy, the researchers implanted the new tissue onto the patients existing bladder. Please note that this was not a bladder transplant nor was the bladder replaced entirely. It was an augmentation that expanded the capacity of the bladder.
The results are encouraging. The researchers found that the engineered bladders continued to develop and appeared normal both anatomically and functionally. There was no evidence of abnormal changes in the tissue. Patients tolerated the surgical procedure well, with hospital stays varying from 23 to 34 days.
Patients were followed for up to 61 months post surgery. Each patient showed an increase in bladder capacity and an improvement in urinary frequency. Upon microscopic examination, the boundary between the original vs. new bladder segments were indistinguishable. Biopsies showed the tri-layered structure with all expected components. This is an amazing breakthrough for bladder repair.
While this has not been applied, as yet, to IC patients, it is a source of great hope. Not only have been able to create new bladder tissue, they may soon be able to create entire organs, such as kidneys for transplant patients. You have to admit that the science is amazing!
Jill O.