Scientists make 'laboratory-grown' kidney
UK: A kidney "grown" in the laboratory has been transplanted into
animals where it started to produce urine, US scientists say.
Similar techniques to make simple body parts have already been used
in patients, but the kidney is one of the most complicated organs made
so far.
A study, in the journal Nature Medicine, showed the engineered
kidneys were less effective than natural ones.
But regenerative medicine researchers said the field had huge
promise.
Kidneys filter the blood to remove waste and excess water. They are
also the most in-demand organ for transplant, with long waiting lists.
The researchers' vision is to take an old kidney and strip it of all
its old cells to leave a honeycomb-like scaffold. The kidney would then
be rebuilt with cells taken from the patient.
This would have two major advantages over current organ transplants.
The tissue would match the patient, so they would not need a lifetime
of drugs to suppress the immune system to prevent rejection.
It would also vastly increase the number of organs available for
transplant. Most organs which are offered are rejected, but they could
be used as templates for new ones.
Researchers at Massachusetts General Hospital have taken the first
steps towards creating usable engineered kidneys.
They took a rat kidney and used a detergent to wash away the old
cells.
The remaining web of proteins, or scaffold, looks just like a kidney,
including an intricate network of blood vessels and drainage pipes.
This protein plumbing was used to pump the right cells to the right
part of the kidney, where they joined with the scaffold to rebuild the
organ.
It was kept in a special oven to mimic the conditions in a rat's body
for the next 12 days.
When the kidneys were tested in the laboratory, urine production
reached 23% of natural ones.
The team then tried transplanting an organ into a rat. Once inside
the body, the kidney's effectiveness fell to 5%.
Yet the lead researcher, Dr Harald Ott, told the BBC that restoring a
small fraction of normal function could be enough: "If you're on
haemodialysis then kidney function of 10% to 15% would already make you
independent of haemodialysis. It's not that we have to go all the way."
- BBC NEWS
|