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Live Cell Therapy (Animal embryonic cells for treating people): Hope, Hype or Hoax?
By Dr. Anthony G. Payne
Live Cell Therapy refers to the introduction of animal embryonic cells into humans as a means of alleviating or curing disease. Some practitioners claim it has rejuvenating effects. Critics and many scientists contend it is worthless and even potentially dangerous: http://www.quackwatch.org/01QuackeryRelatedTopics/Cancer/cellular.html
And yes, there are many accounts of people treated with “live cell therapy” having adverse immunological reactions (immune rejection – Host v. Graft) and of having developed injections caused by viruses and such present in the injected animal material.
On the flip side, there is a large volume of patient testimonials in existence (across many decades) asserting that clinical benefit was realized. And though, yes, testimonials carry little weight in science – a large number of anecdotal (case histories) can point to “smoke in the (proverbial) woodpile”.
Somewhere between “this is utter quackery” and “this is an absolute miracle” lies the truth, in my opinion.
Obviously xenotransplants are part of medicine – and do work to varying degrees. Surgeons implant pig valves to replace faulty human ones. Back in the late 1990s porcine (pig) fetal cells were implanted into the brains of 10 Parkinson’s patients and proceeded to alleviate the disease symptoms for a time (Mind you, the brain does not marshal an immune response against foreign material – not like the rest of the body, anyway).
Another recent clinical trial released its results in March 2001. However, fetal porcine cells were used instead of cells from human fetuses. The study conducted by Genzyme Corporation and Diacrin Incorporation, implanted fetal pig cells into the brains of 10 patients and did sham surgery on the other 8 Parkinson's patients. Though a preliminary study had showed promising results, this placebo/sham trial showed no difference between the two groups 18 months later. (14), (15) Although the use of porcine cells eliminates the abortion controversy, it raises other concerns such as cross-species infection common in xenotransplantation (15). This once again shows that most scientific advances come at a cost.
http://serendip.brynmawr.edu/bb/neuro/neuro01/web2/Rana.html
But is this to say that injections or IVs of sheep, rabbit or shark embryonic material will provide suffering people with relief or even cure? We are back to considering the weight of case histories. Patients like author Valerie Greene (http://www.thefirewithin.net/) report that live cell therapy improved their recovery from devastating disease [Though in Ms. Greene’s case, she had hyperbaric oxygen therapy and blood viscosity-lowering chelation therapy at the same time as live cell therapy, which makes it difficult to know which (if any) was of greatest benefit. We in science know that some folks just get better on their own – treatment or not].
It is difficult to dismiss all these patient histories as being mere coincidence, placebo, spontaneous remission, or natural resolution of disease. I suspect that animal embryonic materials do evoke positive responses in human patients, some of which may ‘enable’ the immune system in such as way as to promote healing (”immunofacilitation”), cause epigenetic changes (outside the genetic core of cells – the nucleus) that switch specific genes on or off with beneficial results, or even engraft and influence the microenvironment in damaged or diseased tissue in such as way as to encourage healing.
But as one trained in physical anthropology and evolutionary biology, I would suspect that fetal material from animals genetically distant to humans would quite naturally have less ‘affinity’ for human tissues and such. A shark, for example, is far removed from us genetically and thus I would expect embryonic material from any species of shark to have far less of an influence on human physiology than, say, a mammalian species like a lamb, rabbit or such. And since primates are much closer to us genetically, one would expect greater ‘affinity’ (Chimpanzees are 97% or so identical to us. Baboons are fairly close too, though not as close as chimpanzees – which is why experimental baboon heart transplants were done years back).
If one is willing to grant that, say, embryonic material
from a sheep or rabbit might produce significant clinical improvement in
certain human diseases or disorders – what about Host v. Graft or Graft
v. Host (An adverse immune response) or infection of the patient by
viruses in the animal tissue injected or infused? The latter can be addresses by using
material from animals raised for generations in a controlled environment
(Something at least one laboratory in the
E.
Whether Dr. Molnar and the Russians and others who have done or are doing live cell therapy are right about it’s safety and efficacy – or not – will ultimately be settled by designing and carrying out well-designed clinical trials.
Dr. Payne can be reached by e-mail at biotheoretician@gmail.com
© 2004 by Dr. Anthony G. Payne. All rights reserved.
Xenotransplantation Xenotransplantation refers to the use of cells or organs of other species for transplantation into humans. Considerable interest has been generated in this topic because of the shortage of human organs for
transplantation. The Health Service defines xenotransplantation to include any procedure that involves the transplantation, implantation, or infusion into a human recipient of either (a) live cells, tissues, or organs from a nonhuman animal source or (b) human body fluids, cells, tissues or organs that have had ex vivo contact with live nonhuman animal cells, tissues, or organs (http://www.fda.gov/cber/gdlns/xenophs0101.htm). A single term "transplantation product" now covers all living material used in any category of xenotransplantation. Xenotransplantation products developed from living cells of non- human animals are currently being investigated in clinical trials and preclinical studies. These have the potential to ameliorate disease and fulfill the need created by shortage of human material. The realization of this potential will depend on the success in overcoming immunological barriers and addressing concerns about transfer of adventitial infectious agents (Chapman and Bloom 2001).
Cell therapy and regenerative medicine Regenerative medicine aims at restoring body function based on an understanding of the biological processes − embryology, organogenesis, cell signaling, growth factors and stem cell biology − that are critical in the original formation and normal function of organs and tissues. It is an emerging area of biotechnology, which develops products designed to recreate the conditions that support the growth of cells and tissues, and thereby harness the body’s inherent ability to repair damage caused by disease, trauma or age. Regenerative medicine, aiming at tissue restoration and functional regeneration, uses three strategies: transplantation of cells to form new tissue in the transplant site, implantation of bioartificial tissues constructed in vitro, and induction of regeneration in vivo from healthy tissues adjacent to an injury. Gene therapy can also be applied for regeneration. There is an enormous potential of renewing body tissues with the help of natural signals that control its growth. Innovative therapies based on this knowledge can be applied to a broad range of unmet medical needs.
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