Head transplant

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A head transplant is a surgical operation which involves the grafting of one organism's head onto the body of another. It should not be confused with another, hypothetical, surgical operation, the brain transplant. Head transplantation involves decapitating the patient. Although it has been successfully performed using dogs, monkeys and rats, no human is known to have undergone the procedure.[1]

Since the technology required to reattach a severed spinal cord has not yet been developed, the subject of a head transplant would become quadriplegic unless proper therapies were developed. This technique has been proposed as possibly useful for people who are already quadriplegics and who are also suffering from widespread organ failures which would otherwise require several distinct and difficult transplant surgeries. It may also be useful for people who would rather be quadriplegic than dead. The consensus on the ethics of such a procedure is negative.[2]

History[edit]

Transplantation of a dog-head in the GDR by Vladimir Demichow in 13. January 1959

As the book Stiff: The Curious Lives of Human Cadavers explains:

On May 21, [1908, Charles] Guthrie succeeded in grafting one dog's head onto the side of another's neck, creating the world's first man-made two headed dog. The arteries were grafted together such that the blood of the intact dog flowed through the head of the decapitated dog and then back into the intact dog's neck, where it proceeded to the brain and back into circulation. Guthrie's book Blood Vessel Surgery and Its Applications includes a photograph of the historic creature. Were it not for the caption, the photo would seem to be of some rare form of marsupial dog, with a large baby's head protruding from a pouch in its mother's fur. The transplanted head was sewn on at the base of the neck, upside down, so that the two dogs are chin to chin, giving an impression of intimacy, despite what must have been at the very least a strained coexistence....too much time (twenty minutes) had elapsed between the beheading and the moment the circulation was restored for the dog head and brain to regain much function. Guthrie recorded a series of primitive movements and basic reflexes, similar to what Laborde and Hayem had observed: pupil contractions, nostril twitchings, "boiling movements" of the tongue.[3]
The first dog heads to enjoy, if that word can be used, full cerebral function were those [of] transplantation whiz Vladimir Demikhov, in the Soviet Union in the 1950s. Demikhov minimized the time that the severed donor head was without oxygen by using "blood-vessel sewing machines." He transplanted twenty puppy heads—actually, head-shoulders-lungs—and forelimbs units with an esophagus that emptied, untidily, onto the outside of the dog—onto fully grown dogs, to see what they would do and how long they would last (usually from two to six days, but in one case as long as twenty-nine days).

In his book Experimental Transplantation of Vital Organs, Demikhov included photographs of, and lab notes from, Experiment No. 2, on February 24, 1954: the transplantation of a one-month-old puppy's head and forelimbs to the neck of what appears to be a German shepherd. The notes portray a lively, puppy like, if not altogether joyous existence on the part of the head:

09:00 The donor's head eagerly drank water or milk, and tugged as if trying to separate itself from the recipient's body.

22:30 When the recipient was put to bed, the transplanted head bit the finger of a member of the staff until it bled.

February 26, 18:00. The donor's head bit the recipient behind the ear, so that the latter yelped and shook its head.

Demikhov's transplant subjects were typically done in by immune reactions.[3]

In 1959, China announced they had succeeded in transplanting the head of one dog to the body of another twice.[4]

Dr. Vladimir Demikhov's work, among others, was deeply influential for the future science of organ transplant,[5] as he pioneered many different forms of transplant in the 1940s and 1950s, including the use of immuno-suppressants.[3] His work was well known by other scientists and during the 1950s and 1960s, numerous heart transplants were performed on dogs in the United States by Dr. Norman Shumway of Stanford University and Dr. Richard Lower of the Medical College of Virginia. The first human heart transplant was performed by Christiaan Barnard in South Africa, in 1967, however, as they did not have the chemical agents to utilize immuno-suppressants, the patient receiving the transplant did not do very well.[6]

On March 14, 1970,[7] a group of scientists from Case Western Reserve University School of Medicine in Cleveland, Ohio,[6] led by Robert J. White, a neurosurgeon and a professor of neurological surgery who was inspired by the work of Vladimir Demikhov, performed a highly controversial operation to transplant the head of one monkey onto another's body. The procedure was a success to some extent, with the animal being able to smell, taste, hear, and see the world around it. The operation involved cauterizing arteries and veins carefully while the head was being severed to prevent hypovolemia. Because the nerves were left entirely intact, connecting the brain to a blood supply kept it chemically alive. The animal survived for some time after the operation, even at times attempting to bite some of the staff.[8] In 2001, Dr. White successfully repeated the operation on a monkey.[9]

White later wrote:

"…What has been accomplished in the animal model - prolonged hypothermic preservation and cephalic transplantation, is fully accomplishable in the human sphere. Whether such dramatic procedures will ever be justified in the human area must wait not only upon the continued advance of medical science but more appropriately the moral and social justification of such procedural undertakings…what has always been the stuff of science fiction - the Frankenstein legend, in which an entire human being is constructed by sewing various body parts together - will become a clinical reality early in the 21st century… brain transplantation, at least initially, will really be head transplantation - or body transplantation, depending on your perspective… with the significant improvements in surgical techniques and postoperative management since then, it is now possible to consider adapting the head-transplant technique to humans."[10]

In 2002, other head transplants were also conducted in Japan in rats. Unlike the head transplants performed by Dr. White, however, these head transplants involved grafting one rat's head onto the body of another rat that kept its head. Thus, the rat ended up with two heads.[11] The scientists said that the key to successful head transplants was to use low temperatures.[12]

A human head transplant would most likely require cooling of the brain to the point where all neural activity stops. This is to prevent neurons from dying while the brain is being transplanted. Ethical considerations have thus far prevented any reported attempt by surgeons to transplant a human being's head.

Creating a headless body[edit]

In 1996, William Shawlot and Richard Behringer of the University of Texas MD Anderson Cancer Center in Houston created 125 headless mice by knocking out a gene called Lim1 in the developing embryos. Only four of the headless embryos survived until birth, and with no nostrils, no mouth to breathe through, they died immediately. Lim1 belongs to a set of genes, called the homeobox genes, that are essential to embryonic development—and that are present in all animals. Lim1, for instance, has already been found in frogs. So by studying headless mice, the researchers are finding out what goes into making a human head too. Behringer stated that the frog gene and the mouse gene are almost identical, "I would be very surprised if there wasn’t a human gene."[13]

In 1997, Jonathan Slack, professor of developmental biology at the University of Bath in southwestern England, produced the headless frog embryos by manipulating genes in frog eggs raising the possibility of growing organs for human transplantation.[14]

Future[edit]

Through medical science, it is now known that stem cells are capable of specializing into any type of cell found in the human body. In 1998, Fred H. Gage of the Salk Institute in La Jolla, California, showed that new, functioning neurons are indeed capable of being grown in the adult human hippocampus. This was previously thought to be impossible. The news gives some hope to individuals suffering disabling diseases. Most believe the key to helping individuals whose bodies are incapable of sustaining them is not through arguably crude operations like a head transplant, but through techniques developed through stem cell research. However, the concept of head transplantation may become more popular, as stem cells have been shown by the Wistar Institute of the University of Pennsylvania to repair the severed spinal cords of mice to a functional level. This could mean the subject would no longer be restricted to quadriplegia.

Should the technology to repair damage to the spinal cord be developed, there are many possibilities of what a head transplant could accomplish. A disease such as cancer (non-brain) which afflicts an area of the body such as the lung or bladder, as well as other diseases such as diabetes which affects the pancreas and heart disease, could be cured through the transplantation of the head. People with genetic diseases such as muscle dystrophies whose bodies lose more and more functions over time, eventually leading to death, could benefit greatly from this procedure. These diseases all affect the body but not the head. Should the head be transplanted, these afflictions would be left behind in the old body, while the new body would enable the head transplant donor (not recipient, unless legal identity is carried with the body) to live a longer, healthier life. This would ultimately serve to improve the standard of living for the donors (or recipients) and could potentially double their life spans. Of course, the issue of immune rejection would, however, need to be addressed as it would with other forms of organ or body transplantation. Ethical concerns might persist even if function could be completely restored to the patient: a brain-dead person with a healthy body, suitable for head transplantation, would be in great demand as an organ donor. When used as a head transplant recipient, a body which might have prolonged and enhanced several lives is instead used for the benefit of a single person. Such an outcome will be unacceptable to health systems which suffer from a shortage of organ donors, or could suffer consequent to widespread adoption of head transplantation. Using, where possible, the functional organs of the diseased surplus body may partially alleviate this concern.[citation needed]

In 2013, the neuroscientist Dr Sergio Canavero, director of the Turin Advanced Neuromodulation Group in Turin, Italy, announced the plan for the first head transplant in man. Canavero states that the possibility exists to re-fuse a severed cord by use of fusogens. The project, the Head Anastomosis Venture with Cord Fusion, was announced in July 2013. He wrote:

The greatest technical hurdle to such endeavor is of course the reconnection of the donor (D)'s and recipient (R)'s spinal cords. It is my contention that the technology only now exists for such linkage. This paper sketches out a possible human scenario and outlines the technology to reconnect the severed cord (project GEMINI). It is argued that several up to now hopeless medical conditions might benefit from such procedure.[10][15]

Canavero called the procedure “Heaven surgery,” shorthand for its more full name, “head anastomosis venture.” He speculates that the surgery would take a team of 100 surgeons roughly 36 hours to complete, at an estimated cost of $12,8-million.[15]

The ability of fusogens like PEG (PolyEthyleneGlycol,PEG : see ref.10 for details} to rebridge a transected spinal cord has been confirmed by a 2014 German study.[16]

Popular opinion[edit]

Popular opinion about the potential head transplant has been generally negative.

Robert J. White, the scientist who transplanted a monkey's head, became a leading target for protestors. One interrupted a banquet in his honor by offering him a bloody replica of a human head. Others called his house asking for "Dr. Butcher."

When a surgeon testified in a civil hearing about Dr. Sam Sheppard's murder case, lawyer Terry Gilbert compared Dr. White to Dr. Frankenstein.[17]

The People for the Ethical Treatment of Animals described White's experiments as "epitomizing the crude, cruel vivisection industry."[18]

Dr. Jerry Silver, a coworker of White's and an expert in regrowing severed nerves, stated "I think [head transplants are] fairly barbaric at this point. I do not even see that 100 years from now it is a possibility. If anybody did that today, it would be absolutely horrible. Can you imagine looking around the room, and you're just a head?"[19]

Cultural influence[edit]

  • The 1972 movie The Thing with Two Heads featured a head transplant.
  • In the 2008 film The X-Files: I Want to Believe, head transplants are being carried out illegally in West Virginia by a Russian medical team in order to save the life of a man suffering from cancer.
  • In the Punisher comics, The Russian villain underwent a similar procedure.
  • The book The Day After Tomorrow by Allan Folsom (ISBN 0-446-60041-5) is about a Neo-Nazi plot to transplant Adolf Hitler's head onto a younger body.
  • The Futurama episode "Put Your Head on My Shoulder" revolves around the emergency grafting of Fry's head onto Amy's body until Fry's body can be repaired.
  • An episode of The New Adventures of Superman has its hero in danger of losing his head in a Kryptonite-assisted procedure, for the benefit of a one-shot villain who plans to gain Superman's inhuman strength, and manly figure, by taking his body. While the difficulties of head xeno-transplantation are glossed over, the procedure is identified curiously as a body transplant.
  • In the 1996 movie Mars Attacks! television hostess Nathalie Lake is decapitated and has her head swapped with her pet dog.
  • The The Simpsons episode "Treehouse of Horror II" ends with Mr. Burns' head being grafted on to Homer's body after being crushed.
  • Crank: High Voltage features a character who, after falling from a helicopter, has his head preserved and kept alive by a life support system. It is stated that the machine will only keep him alive temporarily, though he survives for three months after losing his body.

See also[edit]

References[edit]

  1. ^ "The Future of Brain Transplants". NOVA. Retrieved 2012-05-11. 
  2. ^ Krauthammer, Charles (January 19, 1998). "Of Headless Mice...And Men". Time.  Discusses headless cloned humans
  3. ^ a b c Roach, Mary (2004). Stiff: The Curious Lives of Human Cadavers. W.W. Norton & Co. pp. 206–210. ISBN 0393324826. 
  4. ^ "Dog-Head Transplant Claimed by Chinese". Washington Post. December 9, 1959. 
  5. ^ Anna Claybourne, What Are the Limits of Organ Transplants?
  6. ^ a b Pace, Eric (November 25, 1998). "Vladimir P. Demikhov, 82, Pioneer in Transplants, Dies". New York Times. 
  7. ^ Bennun, David. "Dr Robert White". The Sunday Telegraph Magazine. Retrieved 20 March 2013. 
  8. ^ Laura, Putre (December 9, 1999). "The Frankenstein Factor Cleveland brain surgeon Robert J. White has a head for transplanting.". Cleveland Scene. 
  9. ^ "Frankenstein fears after head transplant". BBC News. April 6, 2001. 
  10. ^ a b Sergio Canavero, HEAVEN: The head anastomosis venture Project outline for the first human head transplantation with spinal linkage (GEMINI),2013. Canavero, S. (2013). "HEAVEN: The head anastomosis venture Project outline for the first human head transplantation with spinal linkage (GEMINI)". Surgical Neurology International 4 (2): 335. doi:10.4103/2152-7806.113444.  edit
  11. ^ Young, Emma (3 December 2002). "Infant rat heads grafted onto adults' thighs". New Scientist. 
  12. ^ "Head transplant possible at low temperatures". Chemistry and Industry. December 16, 2002. 
  13. ^ Lori Oliwenstein, Headless Lacking a single gene, mice are born without heads, Discover Magazine, (January 01, 1996)
  14. ^ Robert Barr, Spare Human Parts Debated -- Headless Tadpoles The Latest Oddity To Spur Questions On Cloning Organs, Seattle Times, (October 21, 1997).
  15. ^ a b Rebecca Tucker (2 July 2013). "Human head transplants may be possible this century, neuroscientist says". National Post. 
  16. ^ Estrada, V., Brazda, N., Schmitz, C., Heller, S., Blazyca, H., Martini, R. and Müller, H.W., "Long-lasting significant functional improvement in chronic severe spinal cord injury following scar resection and polyethylene glycol implantation", Neurobiol Dis. July 2014, 67, pp.165-79.
  17. ^ Grant Segall, Dr. Robert J. White, famous neurosurgeron and ethicist, dies at 84, Sun News, (September 16, 2010).
  18. ^ Carla Bennett, Cruel and Unneeded, New York Times, People for the Ethical Treatment of Animals, (August 21, 1995).
  19. ^ Severed Heads 1, New Times Magazine, Page 57.

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