London: Scientists have hailed "a success" the world`s first tissue-engineered urinary tubes grown in the laboratory, using patients` own cells.
The scientists, who have used the lab-grown tubes to treat five Mexican boys with damaged urinary tracts six years back, told `The Lancet` journal that all the patients are now fit and that the grafts have taken and repaired the defects.
The first step in engineering the replacement urinary tubes or urethras by the scientists at Wake Forest Institute for Regenerative Medicine in Winston-Salem, involved taking a
small sample of cells from bladder of each of the boys.
Aged 10 to 14, the boys had suffered injuries in accidents. From these samples, the scientists, led by Prof Anthony Atala, isolated the cells they would need to grow the
new structure that expels urine from the bladder.
These cells, needed to make the muscle, lining and supportive tissue, were nurtured and multiplied in the lab for weeks until they were plentiful enough for the job. They were
then placed onto a biodegradable mesh that was shaped into a tube and sized to be a perfect fit for the patient.
After a week of incubation to allow the cells to take to the mesh, the lab-grown grafts were surgically transplanted into the patients.
Six years on, the grafts are doing well, looking and functioning exactly like a normal urethra in the boys who are now entering their teens, say the scientists.
Without this revolutionary treatment, the boys would have required an artificial graft that has up to a 50 per cent chance of failure, or would have faced a life of probably
incontinence and repeated urine infections, they say.
Professor Chris Mason, an expert on regenerative medicine at University College London, was quoted by the `BBC` as saying, "Totally grown in the lab, these urethras, living tubes which convey urine from the bladder, highlight the power
of cell-based therapies.
"When an organ or tissue is irreparably damaged or traumatically destroyed, no amount of drugs or mechanical devices will restore the patient back to normal. If the goal
is cure, then cell-based therapies are the answer.
"Using living cells as `medicines` is a major step-change in clinical practice. Cell-based therapies complement drugs and devices by aiming to cure the large unmet
medical needs of our generation, including blindness, heart failure, Parkinson`s disease and stroke."