X-Message-Number: 11312
Date: Tue, 23 Feb 1999 17:34:07 -0500
From: Jan Coetzee <>
Subject: everyone donor

I hope the animal rights activists don't get their way!

J.C.
==============================================
<P>
But animal rights activists say the whole process is unnecessary.
Rather than killing animals for organs, they suggest everyone be
considered an organ donor unless they specifically request an
exemption, the opposite of the current policy.
<P>
=============================================


Northeast, scientists are growing pigs whose DNA has been altered
with human genes.
<P>
It sounds like the stuff of science fiction, yet officials at
Alexion Pharmaceuticals Inc. say they are close to figuring out how
these pigs can figure in the treatment of human organ failures,
spinal cord injuries and illnesses such as Parkinson's disease.
<P>
The idea of transplanting animal parts to humans, called
xenotransplantation, isn't new. But, until recently, nobody knew how
to keep the human body from rejecting the organs.
<P>
About 18 000 organ transplants are performed in the United States
each year and more than 40 000 patients are waiting for donor
organs, according to the United Network for Organ Sharing. About 10
Americans die each day waiting for transplants, network officials
say.
<P>
Alexion's first altered pigs, created with the help of
researchers at Virginia Tech in the early 1990s, contained a human
gene called CD-59. Scientists hoped the grafted gene would trick the
human body's immune system into believing that the pig parts were
human.
<P>
While transplanted organs from those pigs were able to survive
for a couple of days in their new host, the body eventually rejected
the parts.
<P>
A major breakthrough came last year when the small biotechnology
firm, working with scientists in Australia, figured out a way to
alter a sugar-like molecule in pig cells so that human antibodies
would not recognise it as foreign.
<P>
The molecule had been acting as a magnet for human antibodies,
betraying the fact that the transplanted tissue was not human.
Alexion quickly patented the process.
<P>
"If you now take cells from those animals and challenge them
with human serum, they are almost indestructible in the lab,'' said
Stephen P. Squinto, the chief technology officer at Alexion.
<P>
Scientists at Alexion have already transplanted brain cells from
their transgenic pigs into rodents with a syndrome similar to
Parkinson's, a degenerative nerve condition that affects motor
function.
<P>
The transplanted cells not only survived, they became
neurotransmitters in the animals' brains and helped correct the
tremors, Squinto said.
<P>
The same experiments are now being conducted in baboons. If those
experiments work, Alexion hopes to begin human trials by the end of
the year. Researchers hope that within 15 years humans will be able
to receive permanent organ transplants from swine.
<P>
The company also has seen remarkable results by transplanting
cells from a pig's snout into the damaged spinal columns of rodents,
Squinto said. The cells replace the damaged protective sheath around
the spine and allow nerve cells to regenerate.
<P>
"Would we expect that we will be able to take a person who is a
paraplegic and have them walking or running in the Olympics?''
Squinto said. "No, I don't think that's the case. But restoring
some function to that person is certainly a goal.''
<P>
Xenotransplantation faces stiff opposition from some in the
medical community and from animal-rights activists. Alexion was
unwilling to allow a reporter or photographer to visit their
facilities, in part because they could be targeted by animal rights
protesters.
<P>
Among the medical concerns: the fear that transplanted organs
could bring with them new diseases caused by viruses now living only
in pigs. A virus originally transmitted from chimpanzees to humans
is believed to have caused AIDS.
<P>
Because a transplant patient's immune system is suppressed with
drugs, xenotransplantation provides an ideal environment for pig
viruses to mutate, said Dr. Thomas Murray, director of the Center
for Biomedical Ethics at Case Western Reserve University.
<P>
``There are risks to third parties here,'' he said. "If you get
an organ from a cadaver, you decide whether to accept that risk for
yourself. But if you get an organ from a pig, many more people are
put at an unknown risk.''
<P>
The Food and Drug Administration had temporarily banned
animal-to-human transplant experiments because of pig viruses, but
dropped the ban late in 1997. Scientists now believe they have
identified all the so-called retroviruses that are unique to pigs
and can screen for them, Squinto said.
<P>
Dr. David Hull, director of the clinical transplant programme at
Hartford Hospital, is excited by the idea of farms filled with
transplantable organs.
<P>
The technology could dramatically improve the lives of thousands
of people, many of whom can no longer even get out of bed because
their own hearts or livers are failing, he said.
<P>
"You'd be able to meet the needs of everybody,'' he said. ``You
would save a tremendous amount of money and lives.''
<P>
But animal rights activists say the whole process is unnecessary.
Rather than killing animals for organs, they suggest everyone be
considered an organ donor unless they specifically request an
exemption, the opposite of the current policy.
<P>
"That is the way to save a lot of money, and it would save a lot
of suffering,'' said Sandra Larson, with the New England
Anti-Vivisection Society

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