No, a full brain transplant is not currently possible and remains in the realm of science fiction due to immense technical and ethical hurdles, primarily the inability to reconnect the spinal cord and nervous system to restore function, control, and sensation, as well as challenges with immune rejection and preserving consciousness. While partial brain tissue transplants have been explored, a whole brain transfer faces obstacles like nerve regeneration, cranial nerve reconnection, and preventing the body's rejection of the foreign brain, making it far from a reality.
As of now, no successful human head transplant has been performed, and the conversation surrounding the topic remains contentious, reflecting a blend of hope, caution, and ethical considerations in the face of groundbreaking medical possibilities.
Organs that have been successfully transplanted include the heart, kidneys, liver, lungs, pancreas, intestine, and thymus. Some organs, like the brain, cannot be transplanted. Tissues include bones, tendons (both referred to as musculoskeletal grafts), cornea, skin, heart valves, nerves and veins.
While no full brain transplants have been performed on humans, there have been attempts in the world of animal testing. Some experiments have involved transplanting parts of the nervous system or brain from one animal to another, but these have not resulted in lasting success.
So, brain transplantation currently remains the stuff of science fiction and academy award-winning cinema. Feasibility according to basic anatomy and physiology make developing such a complex procedure unlikely.
These can be supplied by connecting the blood vessels that supply the brain with an artificial blood substitute or by immersing the blood in an artificial cerebro-spinal fluid and oxygenating that directly. Guinea pig, dog and monkey brains have all been kept alive for hours or even days after being removed.
Lungs are the most difficult organ to transplant because they are highly susceptible to infections in the late stages of the donor's life. They can sustain damage during the process of recovering them from the donor or collapse after surgeons begin to ventilate them after transplant.
Ethics aside, the brain is a delicate organ, and the spinal cord, which connects to the brain, does not recover well after being cut. While there have been animal experiments involving transplanted heads, most animals that have been subjected to these experiments died within hours or days.
Human head transplants are also known as cephalosomatic anastomosis, and at the moment, are not actually possible and likely won't be before 2030. Some researchers have tested a human head transplant on cadavers; they've also been tested on animals.
Canavero will need the support of his peers in order to move forward on the operation which could cost around $15m. Cardiothoracic surgeon, Dr Raymond Dieter, a former president of the International College Of Surgeons, said one of the biggest concerns with the procedure was keeping the brain alive during the surgery.
Multiorgan transplants, especially triple transplants, remain rare. U.S. medical centers, including all three Mayo Clinic campuses — Arizona, Florida and Minnesota — have performed 62 heart, liver and kidney transplants since 1989, says Bashar A.
Anyone over age 18 may choose to donate their brain after death. A legal guardian must provide consent for those younger than 18. This includes people who have a brain disorder and those with healthy brains. In fact, both are needed for this important research.
Kidneys are very successfully transplanted between two people with no matching antigens. A person can make antibodies against another person's HLA antigens. Antibodies can result from blood transfusions, pregnancy, infections or even a viral illness.
All of these studies suggest that the injured adult brain can support the production and incorporation of new neurons. Even if the numbers are small, these results show the adult brain can regenerate neurons after injury. We must analyze the mechanisms controlling these remarkable regeneration processes.
Chronic rejection has widely varied effects on different organs. At 5 years post-transplant, 80% of lung transplants, 60% of heart transplants and 50% of kidney transplants are affected, while liver transplants are only affected 10% of the time.
However, despite the potential, hair cloning is not yet a reality. Current research suggests that we may be at least 10 years away from seeing this technology come to fruition—if it becomes possible at all.
If the brain is central to who we are—containing our thoughts, memories, personality, and consciousness—then theoretically, a brain transplant would transfer these elements from one body to another. The recipient body would gain the consciousness, memories, and identity of the donor brain.
Human cephalosomatic anastomosis and transplantation has never been realized before due to the inability of fusion regarding the spinal cords of the donor and the recipient.
Memory transfer proposes a chemical basis for memory termed memory RNA which can be passed down through flesh instead of an intact nervous system. Since RNA encodes information and living cells produce and modify RNA in reaction to external events, it might also be used in neurons to record stimuli.
To date, no successful human head or brain transplantation has been achieved, and this may be far off in the horizon due to a number of challenges. One of the tallest hurdles to overcome is disconnecting and reconnecting a head or brain to a new body, particularly in severing and reconnecting the spinal cord [13].
Cornea transplant in humans is almost never rejected.
Triple-organ transplants are incredibly rare, with only 59 transplants of the heart, liver, and kidney recorded in the U.S. to date.
“Where extracorporeal machines or transplantation can support or replace the function of organs such as the heart, lung, liver or kidney, the brain is the only organ that cannot be supported or replaced by medical technology.”