What is Xenotransplantation? This is where science tries to use either tissue or organs from animals to humans. They also experiment on crossing animal species as well. Such as putting a pig heart in a baboon just to see how long it will live. This is torture if you ask me. But what makes me the angriest about this whole thing is that they do this to humans also. To justify what they do, scientists pick those with no hope. They feed them their theory on how things should work, and tell them also, if they die, the research information they get from this will go on to help others. I call this false hope. And I really am appalled that they would do this to a family who's loved one is dying. Think about it. Drag out what is already happening? For what? Information? They say this research is for making more organs available for humans through animals. Why not just tell the truth of what this is really about?
Science is so desperate to prove evolution that they will abuse medical science by using Humans to do their research. Why else would they keep trying to transplant chimp hearts into humans, when pigs and cows tissue is a lot less rejected by our immune system? In fact they now use either pig or cow tissue, to replace your heart valve. Not chimp tissue. Which means there's a lot more difference involved in chimps, that are supposed to be 99.4% of our own DNA.
Could this be a cause of the aids virus?
In February 1999 it was announced that a group of researchers from the University of Alabama had studied frozen tissue from a chimpanzee and found that the simian virus it carried (SIVcpz) was almost identical to HIV-1. The chimpanzee came from a sub-group of chimpanzees known as Pan troglodytes troglodytes, which were once common in west-central Africa.
It is claimed by the researchers that this shows that these chimpanzees were the source of HIV-1, and that the virus at some point crossed species from chimpanzees to human. However, it was not necessarily clear that chimpanzees were the original reservoir for HIV-1 because chimpanzees are only rarely infected with SIVcpz.
The findings of this 10-year long research into the origin and evolution of HIV by Paul Sharp of Nottingham University and Beatrice Hahn of the University of Alabama were published in 2003. They concluded that wild chimps became infected simultaneously with two simian immunodeficiency viruses (SIVs) which had "viral sex" to form a third virus capable of infecting humans and causing AIDS.
Professor Sharp and his colleagues discovered that the chimp virus was an amalgam of the SIV infecting red-capped mangabeys and the virus found in greater spot-nosed monkeys. They believe that the hybridisation took place inside chimps that had become infected with both strains of SIV after hunting and killing the two smaller species of monkey.
"It is well established that most new emerging human infectious diseases generally have their origins in other species. A direct method of establishing new infectious human disease would be to implant infected tissues from a nonhuman species into humans thus allowing viruses direct access to human tissues... Seldom, if ever, have we had as much knowledge to prevent a future epidemic. What is lacking is the wisdom to act upon that knowledge." Dr Jon Allan, Virologist, Southwest Foundation for Biomedical Research, Texas, USA.
"If we go ahead with xenotransplantation, it will be a step in the dark" Professor Tony Minson, Virologist, Cambridge University.
"If you are putting your bets on containment, its a lost cause... It is odd that a small number of people in the government are making unilateral decisions about something that could have such long-term consequences for the public." Dr Jon Allan.
"If you have a pig transplant, you may die of leukaemia in twenty years time." Dr David White. Founder of Imutran Ltd., biotechnology company at forefront of development of xenotransplantation.
"There are lots of viruses in pigs. One problem is that pigs have a kind of retrovirus (a retrovirus is the same family of viruses as HIV) which cannot be eliminated from the pig because it is inherited in the pigs own DNA yet can come out as an infectious virus. What we have shown is that up to three strains of pig retrovirus can propagate in human cells, in culture, therefore there is a risk that they could infect humans and might cause disease in humans." Professor Robin Weiss, Virologist, Institute of Cancer Research, London.
3rd November 1999
1963-1964
Dr. Keith Reemtsma, a surgeon at Tulane University in New Orleans, transplants thirteen chimpanzee kidneys into humans. Twelve of the patients survive between nine and sixty days. One patient, however, survives for nine months on primitive immunosuppression drugs with no signs of rejection.
1964
While at the University of Colorado, Dr. Thomas Starzl transplants six baboon kidneys into humans. Survival rates range between nineteen and 98 days, with most patients dying of infections.
1977
Dr. Christian Barnard, the South African surgeon who had performed the first human heart allotransplant in 1967, attempts to use chimpanzee and baboon hearts as bridge organs in patients who had undergone unsuccessful open heart surgery. The recipient of the baboon heart dies after six hours, while the recipient of the chimpanzee heart survives for four days before it is rejected.
1984
Dr. Leonard Bailey leads a group of surgeons who transplant a baboon heart into a newborn infant, known as "Baby Fae," who was born with a poorly developed left side of her heart. She is treated with cyclosporine, an immunosuppressive drug that greatly increased survival rates in allotransplants, and survives for twenty days before the heart is rejected. Some have speculated that blood type incompatibility between Baby Fae and the donor baboon may have played a role in the rejection process.
Dr. Thomas Starzl, now at the University of Pittsburgh, transplants a baboon kidney into a patient with AIDS and hepatitis B, because it is believed baboons are resistant to hepatitis B. The patient survives for 70 days, with no evidence of rejection. He dies of an infection his body could not fight off due to heavy immunosuppression. In the fall of 1999 it is discovered that archived blood and tissue samples of the patient contained baboon cytomegalovirus. It remains undetermined whether the virus had infected human cells or whether baboon cells had migrated from the liver into other tissues.
A Polish surgeon transplants a pig heart into a human patient, who survives for less than 24 hours. The cause of death is attributed to the small size of the heart, which could not support the body's circulatory system.
On Christmas Eve, scientists at Imutran deliver the first transgenic pig, which they name Astrid. The group of scientists, led by Dr. David White, had inserted a small amount of human DNA into a fertilized pig egg, in an attempt to create pig organs that would not be rejected by humans.
1993
Dr. Thomas Starzl again attempts transplanting a baboon liver into a patient suffering from hepatitis B. This patient never regains consciousness after the operation, and dies of infection under heavy immunosuppression. Starzl, who had received permission for several more xenotransplant operations, halts his program to perform further research regarding transplant rejection.
1995
Scientists at Diacrin, Inc. receive FDA permission to begin clinical trials using fetal pig neurons to treat patients suffering from Parkinson's disease. These Phase 1 trials when concluded show efficacy and no safety problems, leading to Phase 2 trials in the late 1990s.
In May, scientists from Nextran announce that they have developed transgenic pig hearts that survive as long as 30 hours inside baboons, as compared to the 60 to 90 minute survival time for regular pig hearts. In July, the FDA approves Nextran's proposal to use transgenic pig livers as bridge organs on up to ten patients.
AIDS patient Jeff Getty receives a transplant of baboon bone marrow cells at San Francisco General Hospital, performed by Dr. Suzanne Ilstaad. Because baboon stem cells are resistant to AIDS, the hope was that they would help Getty's bone marrow produce AIDS-fighting immune cells. The baboon cells do not take; they remain in Getty's system for only two weeks after the transplant. He is still alive and blood tests so far have not revealed any baboon viruses in his system.
1997
Professor Robin Weiss discovers that viruses embedded in every pig cell -- known as porcine endogenous retroviruses (PERV) -- can infect human cells in culture. In the journal Nature he reports that each pig cell carries approximately 50 copies of the PERV virus, and that up to three of them are capable of infecting human cells. As a result, in October the FDA halts all clinical trials until researchers can prove they have developed procedures to detect low levels of PERV virus infection. The moratorium is lifted in January 1998.
1998
Professor Fritz Bach of Harvard Medical School and colleagues call for a moratorium on human clinical xenotransplant trials until the public has debated the risk.
1999
The FDA effectively bans use of nonhuman primates in xenotransplants, citing the risk of cross-species infection.
A study of 160 people who had received various pig tissues and/or cells reveals that none had been infected with the PERV virus. The study was conducted by researchers at Imutran, in collaboration with the CDC and reported in the journal Nature science.
2000
Scientists at PPL Therapeutics in Scotland announce in the journal Nature that they have cloned five piglets for the first time. A team of Japanese scientists announces in the journal Science that they have also cloned a piglet using a different method
Scientists at Infigin announce in the journal Nature Biotechnology that they have produced two litters of transgenic, cloned pigs.
In the journal Nature, Dr. Daniel Salomon of the Scripps Research Institute announces the results of a study which found transmission of the PERV virus during a transplant of pig pancreatic cells into heavily immunosuppressed diabetic mice. This finding is the first evidence of cross-species transmission of a retrovirus during a transplant. Salomon found that the mice developed PERV infections that lasted for as long as two months before going dormant.
The British animal rights organization Uncaged Campaigns receives leaked documents of an Imutran study of the survivability of pig organs in primates over a five-year period. The study showed the average survival time was thirteen days, with a quarter of the primates dying within two days.
The International Society for Heart and Lung Transplantation issues a report which advises that clinical xenotransplantation trials should not be undertaken until authorities have determined a minimal virus risk, and until 60% of pig organs survive in non-human primates for a minimum of three months. However, they conclude "Xenotransplantation has the potential to solve the problem of donor organ supply, and therefore research in this field should be actively encouraged and supported."
2001
The United Kingdom Xenotransplantation Regulatory Authority (UKXIRA) publishes its third annual report, which states "Although alternative therapies are in development, xenotransplantation may still offer the prospect of a viable treatment within a worthwhile time frame. However, on the basis of current evidence, whole-organ xenotransplantation, as a solution to the ongoing shortage of organs for transplant, appears to be some way off." They conclude that they do not support a moratorium on xenotransplantation, and that until the infection risk is understood, they will assess particular procedures on a case-by-case basis.
2001, March
Preliminary analysis of Phase 2 controlled trials treating Parkinson's disease patients with injected pig neuro cells indicate a setback. Although there were improvements, the study found no difference in the improvements between the patients who had been treated with the pig cells and those who had a placebo treatment.
