This is a beginning, and a solid proof of do-ability. The remaining
problems look almost clear cut and solvable. On top of all that the
threshold for success is actually quite low. Thus the mere step of
replacing one diseased kidney with a partially effective kidney is
practical even with these lousy expectations.
Two dying kidneys cab be replaced one at a time. And as mentioned,
the outcome is still better.
So conservative as this item is, we are far closer to a working
protocol that this suggests. Re-fleshing a failed kidney is an
option. That could lead to the body naturally stimulating steady
kidney improvement with far better results that this says. Just how
did that rat fare as time progressed?
Scientists make
'laboratory-grown' kidney
By James Gallagher
14 April 2013
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.
Scaffolding
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."
He said the potential
was huge: "If you think about the United States alone, there's
100,000 patients currently waiting for kidney transplants and there's
only around 18,000 transplants done a year.
"I think the
potential clinical impact of a successful treatment would be
enormous."
'Really impressive'
There is a huge amount
of further research that would be needed before this is even
considered in people.
The technique needs to
be more efficient so a greater level of kidney function is restored.
Researchers also need to prove that the kidney will continue to
function for a long time.
There will also be
challenges with the sheer size of a human kidney. It is harder to get
the cells in the right place in a larger organ.
Prof Martin Birchall,
a surgeon at University College London, has been involved in windpipe
transplants produced from scaffolds.
He said: "It's
extremely interesting. It is really impressive.
"They've
addressed some of the main technical barriers to making it possible
to use regenerative medicine to address a really important medical
need."
He said that being
able to do this for people needing an organ transplant could
revolutionise medicine: "It's almost the nirvana of regenerative
medicine, certainly from a surgical point of view, that you could
meet the biggest need for transplant organs in the world - the
kidney."
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