Transplanting a head onto a new body. Is it possible? A successful human head transplant took place: the neurosurgeon received an “updated” corpse. Head to body transplant

The first human head transplant in history onto a new body took place. The complex transplant operation continued continuously for 18 hours in China.

As the site learned, Italian neurosurgeon Sergio Canavero reported that the head transplant operation was successful. During the procedure, surgeons were able to restore the functioning of the spine, nerves and blood vessels. It is worth noting that this operation took place on two corpses of people whose brains were still active. Canavero was assisted by highly qualified specialists from Harbin Medical University. Last year, specialists successfully transplanted the head of a living monkey.

It is noted that in the near future Canavero is going to perform a similar operation on a living person. A test operation was performed on the corpse in preparation for a future operation on a living person. The test subject was to be Russian programmer Valery Spiridonov, who suffers from a rare disease, due to which his body almost completely failed. He volunteered.

However, Spiridonov himself recently revealed that the famous surgeon has so far refused to operate on him, and the first test subject will be a resident of China. This situation arose due to the significant funding of medical operations of this kind by the Chinese government. Due to the fact that Russia does not allocate funds for research, Sergio Canavero is forced to comply with some formalities. According to preliminary information, the operation on Spiridonov will be carried out later.

In the community, such operations are still considered ethically wrong, and many experts criticize Canavero, the site reports.

Is a brain transplant possible? How will this process take place? Will the personality change, will new habits develop, or will everything remain the same? And who will be “at the helm”: the person whose brain was transplanted, or the one in whose body the new brain is located? And, probably, the most interesting question that interests many: is it possible to cheat death with the help of transplantation, transfer your personality to another body and live forever?

Scientists' opinions

Scientists have been studying the issue of brain transplantation for many decades, and have still not come to a consensus regarding the possibility of this procedure. Although just recently it was unrealistic to imagine that a person’s head could be transferred to another body, this year the Italian neurosurgeon Sergio Canavero performed such a successful operation. The patient, however, was a corpse.

Angelique Bordey, a professor at Yale University, believes that a brain transplant is possible, although for a positive result it is necessary to transplant the spinal cord, because otherwise the person will not be able to move independently.

In answer to the question of whether the personality and “soul” will be preserved, there is no clear answer. As our bodies grow and develop, our brains change, and the individual's personality will undoubtedly undergo changes during the transplant and recovery process. First of all, due to psychological shock.

The professor says that even a human brain transplant will not give him eternal life. After all, this organ, like any other part of the body, ages. Scientists know how to successfully replace a heart, lungs or kidneys with artificial ones, but they cannot perform a brain transplant. This can lead to neurodegeneration, which can lead to cancer or intellectual decline.

The famous neurosurgeon Khalid Abbed believes that such an operation is quite possible, but for it to be successful it is necessary to be able to connect the nerve fibers of the organ with the spinal cord. This is incredibly difficult, because any spinal cord injury leads to irreversible or severe consequences.

It is expected that after a successful operation the patient's personality will change. Internally, he will become similar to the recipient whose brain was used. After all, it is he who is responsible for the individuality of each person.

Professor of neurosurgery Konstantin Slavin believes that in the foreseeable future science will reach the point where bodies for brain transplants can be created artificially. This will help preserve the patient’s individuality, because the body will be “clean”, without memories.

But even this will not allow a person to cheat death and live forever. Over the years, the brain stops working fully, it ages, and this process remains unchanged. To solve the problem of immortality, it is necessary to find a medicine that will force cells to renew themselves. After all, it is the stopping of cell renewal that leads to the aging of the body.

The first step has been taken

In the fall of 2017, the first head transplant operation was performed on a living person. They transplanted it onto a dead body, but everything went well. The operation was performed by Dr. Zhen Xiaoping, who had tried transplanting monkey heads a little earlier.

Preparation for transplantation lasted almost 3 years. The patient was a programmer from Russia Valery Spiridonov, who was diagnosed with back muscle dystrophy. At first it was assumed that the operation would last 36 hours, but the skill of Chinese doctors was able to reduce the process by almost half.

Operation leader Sergio Canavero says the head transplant is the first step towards a successful human brain transplant. This is the ultimate goal of the entire project. It was created after a statement in 2011 by Dmitry Itskov, a billionaire who planned to transplant a human brain into a cyborg by 2045.

Canavero says China is fighting deadly diseases and its goal is to defeat the aging process, which is also considered a disease and requires treatment.

The unresolved problem of human brain transplantation is the impossibility of complete restoration of the spine. Experiments conducted in which mouse and dog heads were transplanted showed that ethylene glycol injected into the spinal incision helps restore neural connections much more effectively, which increases the chance of successful completion of the operation.

Not so long ago, carrying out such an operation was a fantasy, but today transplantology is successfully moving in this direction. The possibility of brain transplantation into another body would help thousands of terminally ill people. The disabled would be able to walk again, the blind and deaf would be able to see and hear.

Such an operation would give a chance for a normal and fulfilling life to people with diseases of the musculoskeletal system. After all, it is possible not only to transplant a brain, but also to restore damaged areas of nerve connections in the spine.

Barriers to transplantation

When talking about transplanting a brain into another body, people do not think about the fact that there is also a negative side of the coin, which is far from so rosy and carefree. Is it possible to transplant a brain, will it be damaged during the operation, how will the body perceive such stress, will it affect the psyche?

Transplantation is incredibly difficult. When transplanting any other organ, its fusion with the new body plays an important role. Each piece of tissue, nerve, and vessel must be properly connected to each other. Damage to nerve fibers in the brain prevents signals from passing between the organ and the body, so the brain cannot properly respond to stimuli and control the corresponding tissues.

Damage during transplantation is inevitable. It takes a lot of time after the operation for the body to restore the previous connections and for the blood vessels and nerve endings to grow together.

The success of the operation depends on the human body and its immune system. The protective function of the body rejects all foreign elements, so it may not accept the new organ. To stop the immune system from working, the patient takes immunosuppressants before the transplant. They increase the chance of a successful operation, but the chance of catching the disease also increases.

The danger of brain transplantation is associated with its connection to the spinal and bone. Their connection helps transmit signals through the largest nerve, the damage to which cannot yet be repaired. If this nerve is disconnected, then our brain will not be able to receive signals from other organs and systems. Only the ability to chew and move the facial muscles will remain.

Neither the lungs, kidneys or heart will be able to function anymore. This will lead to the death of the patient. Even if the brain lives, the body will remain motionless, dead. And when it is possible to successfully remove an organ from the skull and transplant it into another person, some parts may be damaged, which will lead to the loss of some functions. Therefore, transplantation is possible only with the head.

Head transplant

Scientists believe that the brain can live separately from the body. After all, the experience of doctors shows that even after a long stay in the condition, the patient can recover and live a full life. This suggests that the brain is not yet fully understood. If the transplant process is carried out correctly, all functions and memory will be preserved, and the patient’s intelligence and thinking abilities will not be affected.

If you transplant not the organ itself, but the head, then the chance of damage is minimized. But the problem of the new body’s rejection of foreign tissue still remains. The immune barrier is still insurmountable. Experiments on animals have shown that the head can function on a new body, but the duration of its life is extremely short.

Science is constantly evolving, so in the future it will be possible to overcome the immune barrier. The chances that foreign tissue will take root are small, but they exist. After all, if the head in the new body does not perform its functions, then why do such an operation at all?

It is much more effective to use specially created systems that will help make life easier for paralyzed people than to try to transplant their brain into another body.

The famous theoretical physicist Stephen Hawking uses a “smart” system to communicate with people. His body is paralyzed, only one finger on his hand and a muscle on his face work. The upgraded chair has a speech synthesizer connected to the finger, and a sensor is connected to the cheek that allows you to control the computer.

Some scientists believe that it is much easier to grow new cells than to transplant a brain. While the head is in saline solution, a new body can be created from one cell that will not be rejected. It will be considered its own, only renewed, so all the tissues will be able to fully take root and will not die off.

Controversial issues

To prevent the immune system from rejecting the new organ, it is necessary to find two patients who are histocompatible. That is, when transplanting, it is important to find a body that is ideal as a donor.

When talking about a brain transplant to another person, it is difficult to understand who to call a donor and who to call a recipient. After all, in theory, a donor is the person whose organ is transplanted. But if a brain transplant is performed along with a person’s memory and personality, then the body is the recipient.

The question of where to store the separated head while the operation lasts has not been resolved. The brain can live separately for no more than 7 minutes, and then the neurons die off, and it is no longer possible to restore the lost areas. To successfully complete a transplant, much more time than 7 minutes is required.

It is necessary to find a suitable place for the operation, equipment, and comply with all conditions. Many countries prohibit organ transplants, which also needs to be taken into account.

Is it possible to transplant a human brain? Scientists believe that it is too early to talk about the success of the operation, because a full recovery process, both psychological and physical, is practically impossible.

On July 18, a little over 100 years ago, in 1916, Vladimir Demikhov was born into a peasant family - a man who stood at the origins of domestic transplantology.

He was the first to make an artificial heart and implanted it in a dog who lived with him for 2 hours. Demikhov was also the first to transplant a separate lung, a heart together with a lung, a liver, and developed the procedure for mammary coronary bypass surgery. One of the areas of his work was attempts at head transplantation. Back in 1954, he first implanted a second head on a dog and successfully repeated this procedure several times.

Today, a heart transplant is still one of the most complex operations in the world, but it is no longer unique. More than 200 such operations are performed annually in Russia alone. Liver transplantation is gradually becoming a routine procedure, as are many other operations developed by Demikhov. Only head transplantation still remains one of the unsolved problems of transplantology - science has advanced a lot over the past 60 years, but has not yet reached the point of head transplantation to a living person.

MedAboutMe figured out why it is more difficult to transplant a head than a heart, and what problems, besides medical and physiological ones, confront scientists in this field.

Body or head?

The essence of a head transplant operation is to graft the head of one living creature onto the body of another. It can be carried out in two ways:

The head of the “receiving party” is not removed - and this is exactly the kind of experiment Demikhov did. In total, he created 20 two-headed dogs. The head is removed from the body, meaning the donor's head should remain the only one on the body.

It’s worth noting right away: the question of which of the two organisms is the donor (the one who shares the organs) and which is the recipient (the one to whom the organs are transplanted) has not yet been finally resolved:

On the one hand, the body is 80% of the organism, and from this perspective the head is transplanted onto a new body. Both in the media and among a significant part of scientists they talk about head transplantation. On the other hand, by default we consider the head to be a more significant part of the body, because it contains the brain that defines a person as a person. From this perspective, it would be more correct to talk about a body transplant. Medical problems of head transplant

Scientists talk about three main problems that cannot yet be solved with head transplantation.

Risk of graft rejection.

Well, let’s assume that the achievements of modern medicine will allow us to cope with this problem, at least for a short period of time. In the end, even in the late 1950s, after Demikhov’s operation, dogs with two heads and even a two-headed monkey lived for some time after the operation - although not for long, well, medicine was much less developed.

Risk of brain death when cut off from blood supply.

To keep neurons in the brain alive, they need a continuous flow of blood, which carries oxygen and nutrients and removes harmful waste products from nerve cells. Cutting off the blood supply to the brain even for a short time leads to its rapid death. But this problem can be solved with the help of modern technologies. For example, when transplanting a monkey, the head was cooled to 15°C, which significantly prevented the death of brain neurons.

The problem of connecting parts of the central nervous system of the body and head.

This question is the most difficult and has not yet been resolved. For example, breathing and heartbeat are controlled by the autonomic nervous system and the brain stem. If you remove the head, the heart will stop and breathing will stop. In addition, all the neuron processes coming from the skull to the spinal cord must be correctly connected, otherwise the brain will not receive information from the body's sensors and will not be able to control movement. But the spinal cord is not only motor activity. This is also tactile sensitivity, proprioception (sensation of your body in space), etc.

Skeptics also remind that if scientists and doctors learned to fuse a severed spinal cord - and this is what we are talking about in this case, then first of all this technology should be applied to hundreds and thousands of people with existing spinal cord injuries.

In 2016, an international team of scientists from the USA and South Korea proposed using polyethylene glycol (PEG) to splice damaged nerve tracts in the spinal cord. During the experiment, scientists were able to at least partially restore the severed spinal cord of 5 out of 8 animals: they were alive a month after the start of the experiment and demonstrated the ability to move. The remaining animals died paralyzed.

Later, scientists from the University of Texas improved the solution for splicing the spinal cord, enhancing its properties with graphene nanoribbons, which should act as a kind of scaffold for nerve cells.

There is also evidence that South Korean scientists were able to restore the ability to move in rats with a severed spinal cord and achieve good results in a dog whose spinal cord was damaged by 90%. True, the degree of evidence of these experiments is quite low. The scientists did not provide evidence that the spinal cord was actually destroyed in the experimental animals, and the sample was too small.

In any case, according to experts, after doctors learn to confidently restore a severed spinal cord, head transplantation will be possible, at best, only after 3-4 years.

Psyche, ethics and two brains of the body

The listed problems are not the only ones. Even the theoretical possibility of a body transplant raises many questions on the borders of ethics, physiology and psychiatry.

Scientists believe that we perceive the world not only “through our heads,” but also to a large extent through bodily sensations. The role of proprioception in human life is huge - we cannot realize it, since it is part of human existence. However, psychiatrists describe rare cases of loss of the sense of proprioception - it is difficult for such people to exist in this world.

Another important point. The brain is the largest collection of nerve cells in the human body. But there is another extensive nerve network - the enteric nervous system (ENS), located in the walls of the gastrointestinal tract. It is sometimes called the “second brain” because it can “make decisions” without the participation of the brain, while using the same neurotransmitters as the latter. Moreover, 95% of serotonin (the “mood hormone”) is produced not “in the head,” but rather “in the intestines,” and it is this hormone that largely determines our understanding of the world.

Finally, in recent years there has been increasing evidence that the gut microbiome also has an impact on the formation of human personality.

All these facts raise doubts among scientists that it is the head that determines a person’s personality. It is quite possible that the bodily part of the personality will have such an influence on the transplanted head that the question will still arise: who is the master in the body? And how the human psyche will transfer this new view of the world is not yet known.

Russian head transplant

Over the past couple of years, information has periodically flashed in the media about the decision of a Russian resident, programmer Vitaly Spiridonov, to become a “guinea pig” and take part in the world’s first head transplant operation on a living person. Spiridonov suffers from an incurable disease - Werdnig-Hoffmann disease, congenital spinal amyotrophy. His muscles and skeleton atrophy, which threatens his death. He gave Sergio Canavero's consent to participate in the operation, but the procedure is postponed.

Chronicles of head transplantation 1908. French surgeon Alexis Carrel was developing techniques for connecting blood vessels during transplantation. He transplanted a second head to the dog and even recorded the restoration of some reflexes, but the animal died a few hours later. 1954 Soviet surgeon Vladimir Demikhov, also as part of the development of a coronary bypass procedure, performed a transplantation of the upper body - the head with the front legs - on a dog. The grafted body parts could move. The maximum lifespan in one case was 29 days, after which the animal died due to tissue rejection. 1970 American neurosurgeon Robert J. White cut off the head of one monkey and connected the body's blood vessels to the head of another animal. He also did not touch the nervous system. At the same time, White used deep hypothermia (cooling) to protect the brain at the stage of its temporary disconnection from the blood supply. The grafted head could chew, swallow and move its eyes. All monkeys participating in such experiments died within a maximum of three days after surgery from the side effects of high doses of immunosuppressive drugs. year 2012. After several head transplant experiments by other scientists, the experiments of Chinese transplantologist Xiaoping Ren became famous. He successfully transplanted the head of one mouse onto the body of another - at best, the experimental animals lived for six months. year 2013. Italian transplantologist Sergio Canavero made a statement about the possibility of human head transplantation. 2016 Canavero and Ren reported successful attempts at head transplantation in mice, rats, dogs and monkeys, and equally successful attempts at reconnecting severed spinal cords in animals using fusogen proteins. True, the scientific community doubts the reliability of the published results, since instead of a video, only photos of dubious quality were presented. And Ren and Canavero themselves admitted that we are talking about restoring only 10-15% of the nerve connections in the spinal cord, at best. According to scientists, this should be enough for at least some small movements. 2017 Xiaoping Ren reported a successful head transplant on a human corpse. True, it turned out to be quite difficult to prove success, because it is unclear whether it is possible to restore the nerve connections of the spinal cord in this way. Bright future. Sergio Canavero (Italy) and Xiaoping Rei promise to transplant a head to a living person in the coming years. Vitaly Spiridonov hopes to become one. But it seems that the first “test subject” will be a Chinese citizen - this is more profitable for business. Conclusions Transplantology is developing by leaps and bounds. The annual number of kidney transplants in the world is measured in tens of thousands, liver and pancreas transplants in the thousands. Surgeons have learned how to transplant limbs and faces, a woman with a transplanted uterus recently gave birth, and in 2014 a penis was successfully transplanted. Sooner or later, humanity will cope with a head (or body) transplant. But for now we can say for sure: we will not see a living person assembled from the body and head of different people any time soon. Today medicine is clearly not ready for this. Take the testTest: you and your health Take the test and find out how valuable your health is to you.

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Expert: “This is very nice PR!”

Italian surgeon Sergio Canavero performed a human head transplant in China. According to him - successful. Meanwhile, the public is perplexed, because we are talking about a head transplant to a corpse. Why transplant a head into a corpse?

Canavero became famous in Russia after programmer Valery Spiridonov, suffering from a serious illness,...

Now Canavero has refused this operation. According to Spiridonov, the surgeon received funding specifically in China and specifically for a certain type of experiment...

Russian doctors called the current news about a “successful head transplant” a beautiful PR campaign.

From a PR point of view, this is a very smart move, they are pure adventurers,” Dmitry Suslov, head of the laboratory of experimental surgery of the Pavlov State Medical University of St. Petersburg, told MK. “In fact, the operation that Canavero performed was a training presented as a world sensation.

The expert said that similar training operations are carried out by all transplant surgeries in any country in the world that can boast of success in this most complex field of medicine. Moreover, it is mainly young doctors who practice on corpses, who are still afraid to let near a living body.

“We can’t talk about any success here,” Suslov noted. “They took a dead head and sewed it to a dead body.” The only thing we can talk about here is that they worked accurately and sewed it in a purely technically competent manner.

Russian doctors also do not dare talk about any discoveries during the operation. Most of the actions that are needed to sew a head to a body should be perfected to the point of automaticity by any self-respecting surgeon. Every doctor who performs operations on the heart and blood vessels should do the vascular suture practically with his eyes closed. Sutures on large nerves are for neurosurgeons.

As for the past “merits” of the Canavero team, which was also noisily discussed by the whole world - transplanting a head to a monkey, here the doctors also just shake their heads skeptically. According to them, maintaining life in the severed head of an animal is an experiment from the beginning of the last century. The then researchers in white coats were very good at such manipulations.

However, our transplantology still left a small chance of victory in the future for foreign adventurers. Theoretically, it is possible to transplant a head to a living person. And there is even a chance that after the operation both the head and the rest of the body will function normally. But to do this, you will have to make a real scientific breakthrough - learn how to fuse spinal cord neurons.

If someone manages to do this, this will be a Nobel Prize, says Suslov. A huge number of people with spinal injuries will have a chance to get back on their feet and live a full life. But so far such experiments have only been carried out on rats. And at the moment we have only a partial understanding of how this should be done.

When Dr. Canavero announced his grandiose project two years ago, the news shocked the scientific world and, of course, the project was criticized. Despite the skepticism of many scientists and surgeons, the Heaven project attracted the interest of thousands and thousands of physicians who wrote to the Italian scientist.

The first human head transplant will take place in China. The team of specialists will be led by Chinese doctor Ren Xiaoping, assisted by Sergio Canavero. Since the project will be funded by the Chinese government, the patient will be a Chinese citizen, and not Russian Valery Spiridonov, as previously planned.

Sputnik Italia learned from Sergio Canavero what results were achieved within the framework of this fascinating, but ethically ambiguous project:

- Please tell us at what stage the Heaven project is?

“In September, we published our first “proof of principle” research in Korea, conducted in collaboration with Rice University in Texas. Research has shown that mice whose spinal cords were cut, as is done in a head transplant, regained the ability to walk. These operations use an improved version of polyethylene glycol (PEG), so that 24 hours after surgery, nerve impulses begin to pass through the incision site again. A dog whose spinal cord was cut and repaired with PEG was able to run again 3 weeks after surgery.

These were early studies, and critics said we didn't have enough statistics. We were told that nerve impulses pass (through the incision site), but we had to prove that nerve fibers reappear at the incision site. In January, we published the first work that used a method for studying tissues and cells called immunohistochemistry. Using this method, we have proven that nerve fibers grow at the site of the incision.

-And what were the next steps?

To obtain sufficient statistical data, we used large rats for further research. The technique used was diffusion tensor imaging (DTI), which allows you to see the fibers without the need to kill the animals. The rats were divided into two groups: the first group received placebo during surgery, and the second group received PEG. A month later, the rats from the second group could move, but the rats from the first group could not. Later we conducted the same experiment on dogs, and the result was similar. That is, we can now say that mice, rats and dogs with a severed spinal cord can regain the ability to move.

- And the first country in the world where surgery will be performed on humans will be China?

— Yes, the Chinese government wants a Chinese specialist to lead the transplant team of doctors. Therefore, in April we announced that, according to the law of the country, I would assist the Chinese neurosurgeon Xiaoping Ren and his team. It won't be long now, and in October you will learn sensational news.

Why can’t the first person be the Russian Valery Spiridonov, who was the first to offer himself for your operation?

— Here you touched on the main essence of my appeal to Russia. I want to emphasize that in Russia there are surgeons capable of performing such an operation, there is a specially equipped hospital, and there is the necessary money. But at the same time, when representatives of very wealthy Russians, billionaires, contacted me, they emphasized their interest in investing in my project, but not in charity. So now I have lost hope of convincing Russian investors to help me find a donor for a transplant that will save Valery Spiridonov. And I appeal to the Russians: Valery, a Russian citizen, will only be saved by an operation in Russia. China, naturally, will save the Chinese, besides, Valery is a representative of the white race, and he cannot be transplanted with the body of a Chinese, so as not to cause negative psychological reactions.

© photo: Sputnik / Kirill Kallinikov

I officially appeal to the Russian authorities and the Russian people to help me save the Russian citizen Valery Spiridonov. I am ready to assist a team of Russian surgeons during an operation in Moscow. If the authorities are unwilling to intervene, there is another option - crowdfunding. I ask 145 million Russian citizens for financial assistance. There is no other way to save Valery. I ask the Russian people to help save my compatriot. Let Russia, where the great neurosurgeon Surgeon Demikhov began his operations on animal head transplants in the last century, carry out this operation and begin a new era."