Organ piggybank

-- (Credit: Arvind Yadav /CSE)RESEARCHERS are contemplating the use
of pig organs in order to overcome
human donor organ shortage. The pig
organs - such as hearts, kidneys, pancreatic glands - will be extensively
researched and ready for
use probably within 3 years, they contend.

Pigs have been selected because their organs
are about the same size as
human organs and are
similar in shape and structure as well. Also, pigs
produce large litters, and
grow fast - maturing within 10 months.

But a foreign organ,
when placed in a human
body, is likely to be rejected by the body's immune
system. So researchers
have incorporated human
genes in pigs to ensure
that organs taken from
such transgenic pigs are not attacked by the
human immune system.
More than 40 transgenic
pigs have already been produce
scientists (Spectrum, No 245).

Researcher David White, leader of the
research team at Imutran Cambridge-based British company
which is involved in developing
genic pigs, says that when the
work on the project in the mi
was seen as science fiction. Bu
years, scientists in other par
world, too, realised the pot
developing pigs as organ do
now research centres in USA and JAPAN
are also carrying out similar work.

For instance, Nextran in Princeton,
New Jersey, a joint venture of Baxter
Health Care Corp and DNX Corp, a
Princeton-based biotechnology company, has also developed genetically
altered pigs. Organs from these transgenic pigs are being used in baboon
transplant experiments at Duke
University in Durham, North Carolina.
As baboons are closely related to
humans, the results can prove useful.
Says Jeffrey L Platt, the Duke
tion issues such as
approval of human experiments by the
us Food and Drug Administration and
other regulators.

Alexion Pharmaceuticals Inc at New
Haven, Connecticut, is yet another
biotechnology company that is breeding
pigs incorporating human genes.
University researchers in New York and
Oklahoma are working with Stephen
Squinto, Vice President (Research),
Alexion. They are testing pig hearts, livers and lungs on primates
- the highest order of
mammals. Initial results
show that the pig organs
function as long as 48
hours in primates. In earlier experiments, when the
human genes were not
incorporated, grafted
pig hearts in baboons
were rejected in 60 to 90 minutes.

The concept of developing pigs as organ
donors has not been welcomed universally - animal rights organisations
have strongly opposed it,
However, John Wallwork,
Director of the Transplant
Unit at Papworth hospital,
near Cambridge, says that,
"Only animal donors can
close the gap and put an
end to unethical practices
of the impoverished selling kidneys to rich recipients in need of them, and
to distressed relatives
immediately after a sudden death having to face
the ordeal of requests by surgeons for permission to remove organs for use
as transplants,"

Adds John W Fabre of
the University of London,
England, "In societies
where animals are killed
in tens of millions for food ... it would
be difficult to argue on ethical grounds
for a proscription on the killing of a tiny
number of pigs to save the lives and
restore the health of sick and dying patients."