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Animal Transplants: Not the Cure for the Organ Shortage
March 2, 1999
Providence (RI) Journal-Bulletin
Americans for Medical Progress (AMP), a public relations front
for the animal research industry, has launched an irresponsible campaign
to promote animal organ and tissue transplants (xenotransplants), using
the plight of liver transplant patients like football star Walter Payton
to advance its agenda. AMP's board of directors includes Leon Hirsch, AMP
founder and President of US Surgical Corp., which recently sold its xenotransplantation
program to Alexion Pharmaceuticals. Also represented on AMP's board is
Pfizer Pharmaceuticals, a platinum sponsor of World Pork Expo, and national
pig breeding programs. (Several companies in the US are breeding colonies
of pigs with human genes for xenotransplants). AMP is hardly an objective
source for information on xenotransplantation, and Americans should not
be fooled by the group's tactics. Xenotransplantation is not the
solution to the alleged organ shortage.
In the journal Nature (5 March 1998, pp.11-12), transplant surgeon
Abdullah Daar writes that "xenotransplantation will have no immediate effect
on overall transplant numbers," because the technology is still highly
experimental. It faces many obstacles including hyperacute rejection, retroviral
infections, transfer of prions, and severe side-effects of immunosuppressive
drugs. Moreover, animal and human organs differ in their anatomy, production
of hormones, secretion and absorption of enzymes and other chemicals, in
their resistance to disease, and longevity. In 1998, xenotransplant researcher
Thomas Starzl wrote that "the prospect of successful transplantation of
animal organs into humans is still remote." But the public is not holding
its breath. A review of eight studies of attitudes to xenotransplantation
by P.J. Mohacsi, published in the Annals of Transplantation (1998, Vol.3
No.2: 38-45) did not reveal overwhelming support for the technology. And
on 29 January 1999, the Council of Europe, a barometer of public opinion
for its 40 member countries, voted for a world-wide ban on the technology.
In stating that xenotransplantation of animal cells, tissues, and organs
will yield effective treatments for human diseases, AMP exaggerates the
technology's alleged benefits while ignoring its risks. M. M. Swindle at
Medical University of South Carolina, Charleston concedes that, screening
individual animals thoroughly for viruses, bacteria, fungi, and parasites
in a timely fashion prior to xenotransplants would be impossible, leaving
patients, care-givers, and people at large vulnerable to infections. New
viruses may go undetected, and microbiological assays may be unavailable
to screen for them.
US public health agencies acknowledge that xenotransplantation is unsafe,
and dozens of scientific papers have elucidated the risks of xenotransplantation
in great detail. Some have pointed out that, like the AIDS crisis,
the spread of a new zoonotic virus could have the undesired effect of shrinking
the pool of eligible blood and organ donors. Scientists from the Food and
Drug Administration's Center for Biologics Evaluation and Research have
stated that "transplantation of non-human live cells presents a risk of
introducing novel pathogens into the human population."
The use of "bioartificial livers," coated with pig cells to filter
the blood of acutely ill patients awaiting human livers, does not increase
the overall number of organs available for transplant. Moreover,
such devices do not prevent pig viruses from being transmitted to humans.
Experiments using pig cells to treat diabetes, epilepsy, Huntington's and
Parkinson's disease patients have not provided the long-term benefits proponents
hoped for. Studies with pig cells for Parkinson's disease have raised ethical
questions, as patients in control groups had holes drilled through their
skulls but received no treatment. And studies in which cancer patients
were injected with calf adrenal cells to treat pain were not double-blinded.
So the temporary relief these patients experienced could be attributed
to a placebo effect. AMP states that people have used pig heart valves
and animal insulin for decades, and have benefited from polio vaccines
made from monkey kidney cells. But pig heart valves are soaked in
glutaraldehyde before use and are biologically inert. Synthetic valves,
which last longer, are replacing pig valves. Insulin (now produced synthetically,
thereby reducing the risk of allergies and prion diseases) is a purified
compound, not a living preparation. And scientific studies have linked
rare human brain, lung, and bone cancers to polio vaccine contaminated
with simian virus 40. There are alternatives to xenotransplantation. The
Boston-based Campaign for Responsible Transplantation (CRT) publicized
an April 1998 General Accounting Office report on organ donation that identified
a potential US organ donor pool of 150,000 people - more than double the
number needed to alleviate the alleged shortage. The alleged organ shortage
is merely a failure to turn potential into actual donors. Spain implemented
a 'presumed consent law' and has one of the highest organ donor rates in
the world. In December 1998, CRT filed a legal petition with the Department
of Health and Human Services, signed by 55 scientists, physicians, veterinarians,
and concerned laypersons, demanding a ban on xenotransplants. Fueling
the demand for organ transplants is unsustainable and expensive. Aggressive
investment in population-based prevention and rehabilitation programs could
reduce the need for transplants of all kinds. In the meantime, HHS and
the medical community could do a lot more to increase human organ donation
rates.
Alix Fano, MA, Director
Campaign for Responsible Transplantation
PO Box 2751
New York, NY 10163-2751
Tel. (212) 579-3477
CRT, an international coalition of 70 organizations representing over
2 million people, was launched on January 20, 1998 out of concern over
the rush to commercialize xenotransplantation.
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