Study Suggests It May Be Possible to Transplant Animal Embryonic Stem Cells to Grow New Human Organs

In a study published in February in the Proceedings of the National Academy of Sciences, researchers at the Weizmann Institute of Science published the results of their experiments in implanting embyronic stem cells from pigs into mice.

The researchers wanted to establish at what point it was best to implant the embryonic stem cells, so it took stem cells from varying stages of development of the pig embryo, and implanted them in the liver, pancreas and lungs of immune-deficient mice.

The researchers discovered that transplanting embyronic stem cells at too early or too late a stage would not result in new cell growth, but that if transplanted during the correct window of opportunity, the pig stem cells did lead to cell growth in the mice. Dr. Bernard Herring, at the Diabetes Institute for Immunology and Transplantation at the University of Minnesota, told National Geographic News,

What he [lead researcher Yair Reisner] has shown is that there’s a window of opportunity . If you obtain this tissue at a very defined point in time, then you can see development into islets [portions of the pancreas that secrete hormones like insulin] without risks such as teratoma formation. That’s clearly something that makes us feel very strongly that this could be a real opportunity, one that can be translated into tangible benefits much faster than other technologies.

In a statement about the research, Reisner said,

Considering the ethical issues associated with human embryonic stem cells or with precursor tissue obtained from human abortions, we believe that the use of embryonic pig tissue could afford a more simple solution to the shortage of organs.

This finding helps explain, in part, why previous efforts to transplant pig embryonic stem cells failed, since previous research had harvested the cells at a much later gestational age than what Reisner’s study found was optimal.

Of course there are still a number of major hurdles to overcome before such technologies could be used in human beings even if researchers figure out how to make embryonic stem cells produce cells in human beings, including producing pigs free of viruses that could possibly infect human beings and avoiding an immune response to the transplant of such cells.


Pig Stem Cells to Be Used to Grow Human Organs? Stefan Lovgren, National Geographic News, February 15, 2005.

New Organs Could Come from Pig Embryos – Study. Reuters, February 14, 2005.

New Zealand Animal Rights Activists Claim Xenotransplantation Cruel, Dangerous, and Everything Else In The Kitchen Sink

Give New Zealand’s Save Animals From Exploitation some credit for their opposition to xenotransplantation — if you do not agree with one of their arguments against xenotransplantation, they’re hoping you’ll find at least one of their potpourri of arguments appealing.

First, of course, using animals to save human lives is cruel. Save Animals From Exploitation’s Hans Kriek told Stuff.Co.NZ,

Animal organs used for xenotransplantation are not by-products from the slaughterhouse but come from transgenic animals which suffer genetic engineering, cloning, reproductive manipulations, surgical operations and close confinement in unnatural indoor conditions.

But what if you don’t consider the production of transgenic animals particularly cruel? Not to worry — xenotransplantation could also endanger the very existence of humanity. Again, according to Kriek,

All animals harbor viruses, and there is no better way to jump the species barrier than to implant animal organs into humans.

. . .

Xenotransplantation raises the stakes even further by increasing the danger of new, dreadful epidemics.

Which, of course, is why researchers are going to use transgenic animals. But don’t look at the man behind the curtain for the moment.

Instead, ponder the horrific outcome if it should turn out that many people reject the idea that creating transgenic is cruel and the virus situation is exaggerated. What if xenotransplantation actually reaches a point where it is viable?

Well, in that case, Kriek wants us to know that its all about those greedy researchers getting rich off our pain,

Xenotransplantation is heavily promoted by biotech and pharmaceutical companies who would gain huge profits from breeding transgenic animals and selling anti-rejection and other drugs.

Damn bastards! Actually spending large amounts of money researching xenotransplantation and expecting to make a profit off it at the end of the day, when we all know that all other medical technologies from life-saving insulin to heart transplants are completely free and have never involved any animal research at all.


Harvesting organs from animals for human transplants ‘cruel’. Kent Atkinson, Stuff.Co.NZ, February 2, 2005.

Korea Pledges US $10 Million to Biotechnology, Including Xenotransplantation

The government of South Korea announced in January that it would allocate 10 billion won — about US $10 million — to biotechnology research with a large portion of those funds dedicated to researching the production of animal organs for transplantation into humans.

South Korea is hoping to hit it big in the emerging biotech sciences, with government officials calling biotech the “next-generation [economic] growth engine.”

With Europe allowing animal rights and other considerations to limit is ability to support biotech research, Asian countries such as South Korea, Japan and China could become leaders in the field, taking the research that Europe can’t or won’t pursue.


Korea Plans to Commercialize Animal Organs for Humans. Korea Herald, January 12, 2005.

South Korea approves cloning research. Agence-France Press, January 12, 2005.

Australia Imposes Five Year Moratorium on Xenotransplantation

In September, Australia’s National Health and Medical Research Council imposed a five year moratorium on xenotransplantation, prohibiting the transplantation of organs from animals to human beings until more information is known about the potential health risks of such transplants.

National Health and Medical Research Council chairman Alan Pettigrew explained the decision saying,

There were ethical concerns, there were social concerns, but the major area (of concern) were the risks. There were risks to health, not only of the individual but to their immediate family from there to the wider population. There’s still a lot of work that needs to be undertaken. We need at least five years to gain more knowledge before this issue should be considered again.

The council also ruled that even if the moratorium is lifted at some point, that non-human primates should never be used as the source of organs for clinical trials of xenotransplantation.

The council also considered but declined to rule on the use of treatments that utilize animal cells to treat diseases in humans.

The council also considered therapies that use animal cells in human beings, but declined to make a decision saying it needed more information on the health and safety issues involved.


Animal-human transplants frozen. The Sunday Mail (Australia), September 21, 2004.

American Anti-Vivisection Society Demands Immediate Halt to Xeno Research

Following research published in January that observed fused cells resulting from a mixing of human and pig DNA, the American Anti-Vivisection Society fired of a letter to the Department of Health and Human Services demanding an immediate halt to all xenotransplantation research.

Researchers at the Mayo Clinic implanted human blood cells into fetal pigs. Some cells taken from the adult pigs were hybrids — they contained both human and pig DNA material. In addition, the hybrid cells contained the porcine endogenous retrovirus. As New Scientist noted in its summary of the study,

Previous laboratory work has shown that while PERVs in pig cells cannot infect human cells, those in hybrid cells can. The discovery therefore suggests a serious potential problem for xenotransplantation.

The work also suggests a possible route of infection for other viruses that have crossed from animals to humans.

The American Anti-Vivisection Society thinks that potential problem should result in an immediate halt to all such research. In a press release, the AAVS said,

Becuase organs from genetically-altered pigs have been heralded as the potential solution to alleviate the shortage of suitable human organs in the United States and elsewhere, the findings from this study provide an important case to abandon plans to transplant pig-derived cells, organs, and tissues into humans.

“This study clearly illustrates the dangers to public health that are inherent in xenotransplantation,” said AAVS Executive Director, Tina Nelson. “Not only could such transplants further jeopardize the lives of human patients who so desperately need a healthy organ, but also society as a whole, considering the likelihood of the patient also being infected with a dangerous retrovirus that could spread to other people.” The scientists involved postulate that HIV may have originated in this manner when an infected monkey bit a human and their stem cells fused. A retrovirus could also spread among scientists who work with the animals and/or their body parts and fluids.

. . .

“The solution to the organ donor shortage is not to place the burden on other animals but to change the donor system in the U.S. and make it a national priority. Xenotransplantation is similar to putting a filthy band-aid on an infected wound — it will not help but rather worsen the situation,” Nelson added. “I urge Secretary Thompson not to ignore these warnings signs.”

Oh sure, that makes sense — there’s a potential problem here, so lets stop all research!


Health Secretary Urged to Immediately Halt Trans-species Organ Transplants: Study Illustrates Dangers to Humans.

Pig-human chimeras contain cell surprise. New Scientist, January 13, 2004.

Australian Group Recommends Government Allow Xenotransplantation Trials to Proceed

In January, a National Health and Medical Research Council group examining xenotransplantation urged that approval be given for trials of animal to human organ transplantation.

The Working Party on Xenotransplantation announced that its May report will argue that the risks and ethical concerns about xenotransplantation are outweighed by the potential benefits and that human trials of xenotransplantation treatments should be allowed to proceed in that country. In 2002, the Australian government rejected a proposal for a trial using pancreatic cells from pigs to produce insulin in diabetics.

Australia has one of the lowest rates of organ donation in the Western world. In 2001, there were only 801 organs available through donation for almost 2,000 people needing organ transplants.

In its story on the report, CNS News found a religious crackpot in Australia who offered one of the most amusing non-AR explanations of the evils of xenotransplantation that I’ve read yet. According to Peter Stokes, director of Salt Shakers, while it might save lives, xenotransplantation might also make bestiality acceptable! According to Stokes,

We are not ‘animals’ as the humanist would have us believe, therefore we must not allow animal and human tissue to be mixed.

. . .

Image what they would say if we started mixing humans and animal together — this would bolster their [people who support bestiality] argument that ‘we are all the same’ and therefore ‘love between animals and humans is perfectly normal.’

Who could argue with that sort of logic?


Animal organs urged. Jen Kelly, Herald Sun (Melbourne, Australia), January 14, 2004.

Fed: Pig hearts could be a life-saver. Rosemary Desmond, AAP, February 17, 2004.

Animal organ trials to go ahead. Simon Benson, The Daily Telegraph (Sydney, Australia), January 14, 2004.

Pig-to-human organ transplant trials recommended in Australia. Patrick Goodenough, CNSNews.Com, January 14, 2004.