Hidden deep in a Russian forest, and guarded by soldiers with orders to shoot intruders on sight, the medical research laboratories on the outskirts of Moscow were one of the Soviet Union's best-kept secrets.
So the carefully-vetted journalists who were allowed past the forbidding perimeter fence on a cold February morning in 1954 were both apprehensive and curious about what lay ahead. Led to a courtyard outside an austere brick building, they waited in the bright winter sunshine to find out why they had been summoned. For a few minutes, only the sound of birdsong and the rustling of leaves filled the air but then a door slowly opened to reveal experimental surgeon Vladimir Demikhov - accompanied by the strangest looking animal they had ever seen.
Blinking unhappily in the daylight as Demikhov paraded it on its lead, this unfortunate beast had been created by grafting the head and upper body of a small puppy on to the head and body of a fully-grown mastiff, to form one grotesque creature with two heads. The visitors watched in horror and fascination as both of the beast's mouths lapped greedily at a bowl of milk proffered by Demikhov's assistants.
Resembling something dreamed up by Mary Shelley's Dr Frankenstein, it seemed literally incredible. But as the Soviet propaganda machine informed the world, this canine curiosity was both very real - and a scientific triumph.
As revealed in a National Geographic documentary to be screened later this month, the creation of the two-headed dog was the first step in an astonishing race by Cold War scientists to achieve the seemingly impossible - the first ever human head transplant. In pursuing this medical goal, Vladimir Demikhov - and his American rival, Robert White - may seem to be the epitome of immoral scientists who ignored all ethical considerations in their pursuit of scientific advance. But in their own minds, they were brilliant pioneers prepared to think the unthinkable for the greater good of mankind.
Whichever view you take, they cannot simply be dismissed as gruesome fantasists for, as the programme warns, the obstacles which held them back from their ultimate goal are fast being eroded by modern science, and we may have to confront the reality of the first human head transplant much sooner than we care to think.
Although the world's first face transplant has already taken place, the notion of taking the head of one person and transferring it to the body of another still seems far-fetched. But back in the Fifties, despite being utterly incredible to many, it was a branch of science pursued by some of the most respected doctors of the day.
A Soviet hero, Vladimir Demikhov was renowned for his work in the Red Army hospitals during World War II. When peace came, he joined an elite team of Russian doctors ordered by Stalin to beat the West in the field of medicine at any cost. Labouring far from inquisitive eyes in a secret research complex outside Moscow and experimenting freely in his search for new ways of prolonging life, Demikhov was prepared to go where others did not dare.
He believed for example that it was possible to transplant organs like hearts and lungs in human beings. In those days, such a procedure seemed scarcely credible - but Demikhov proved it could be done. Often preferring to work in the dead of night, he showed that the heart and lungs could be taken from one dog and survive in the chest of another.
This laid the groundwork for such landmark operations as the first heart transplant, conducted by South African surgeon Dr Christiaan Barnard, nearly 20 years later. But Demikhov didn't stop there.
He was determined to prove that any human organ could be successfully transplanted, even the brain. To that end, he set about the challenge to create a two-headed dog.
The lights of his laboratory shone into the small hours of that February morning in 1954 as he and his team set about the intricate task of stitching the upper half of the puppy to the larger animal and connecting their blood vessels and windpipes.
As dawn approached, they waited to see if their creation would regain consciousness. Their first sign of success came when the puppy's head woke up and yawned. It was quickly joined by the larger 'natural' head of the mastiff, which gave its new addition a puzzled look and tried to shake it off.
The composite dog was ready to be revealed to the world. Though it had no body of its own, the smaller animal's head was reported to have kept its own personality, remaining as playful as any other puppy, according to Soviet propaganda.
Even the American magazine Time reported the experiment with grudging admiration, describing how the puppy's head alternately growled and snarled with mock ferocity, or licked the hand that caressed it.
"The host-dog was bored by all this but soon became reconciled to the unaccountable puppy that had sprouted out of its neck," their correspondent wrote. "When it got thirsty, the puppy also got thirsty. When the laboratory grew hot, both host-dog and puppy panted to cool off."
After six days, the bizarre hybrid died. But it had survived long enough to worry America, which was desperate to outdo the Soviets in all aspects of science and technology.
Soon the U.S. had a radical transplant programme of its own, led by Robert White, a brilliant and ambitious brain surgeon who, like Demikhov, had seen active service in World War II. In the South Pacific, he had see many men paralysed from the neck down and he was fired with a determination to help these paraplegics live more productive lives. Following Demikhov's triumph with the two-headed dog, the American government helped Dr White establish a brain research centre at the county hospital in Cleveland, Ohio. By day, he performed surgery on people with all kinds of brain injuries and illnesses, but away from his clinics, animals were the focus of his attention.
One key experiment Dr White carried out in 1964 involved removing the brain - though not the head - from one dog and sewing it under the neck skin of another dog.
With its blood vessels connected to those of the host-dog, Dr White managed to keep the isolated brain alive for days, proving not only that the brain could survive away from its own body but that it was immunologically sound - meaning that, unlike a kidney, it could be transplanted without the likelihood of the new 'body' rejecting it.
This was a great breakthrough, but it posed much bigger questions. Did a brain isolated in this way still have the power of thought? Could it in any way be described as 'conscious'?
Since the transplanted brain had no means of expressing itself, Dr White could not answer this question and he seemed to have reached an impasse. But in 1966 he received help from a most unexpected direction.
With Stalin long dead, and the USSR creeping towards economic and technological collaboration with the West, Soviet scientists invited him to visit their laboratories and operating theatres.
During his trip, White learned of new Soviet experiments, in which a severed dog's head had been kept 'alive', not by stitching it onto another dog's body, but using special life-support machinery. Most remarkable of all, the isolated head had continued to show signs of consciousness - its eyes blinking in response to light, and ears pricking at the tap of a hammer on the cases it was in.
This inspired White to take Demikhov's original two-headed dog experiment a stage further: not merely grafting one animal's head on to another's body, but completely replacing one animal's head with another.
This highly complicated operation took White three years to plan and he knew many people would find it morally repugnant. But in the late afternoon of March 14, 1970, he went ahead with the world's first true head transplant, using two rhesus monkeys.
Decapitating both animals, the surgeon successfully managed to stitch the head of one monkey on to the body of the other. He and his team then faced a nervous wait until finally the 'hybrid' monkey regained consciousness, opened its eyes and tried to bite a surgeon who put a finger in its mouth.
The team clapped and cheered as their creation moved its facial muscles, followed their movements with its eyes and even drank from a pipette. But though White regarded the operation as a major success, he knew it had one major limitation.
Because its spinal cord had been severed as part of the operation, the monkey was paralysed from the neck down and it was impossible for the surgeons to reconnect the hundreds of millions of nerve threads necessary for it to regain any bodily movement.
Still, White insisted that such surgery might help a very particular kind of human patient - those paraplegics who faced imminent death because their heads were trapped on bodies failing due to the long-term medical complications which often accompany extensive paralysis.
With a head transplant, these people, he reasoned, would remain paraplegic but their new bodies, 'donated' by patients who were brain dead but otherwise physically healthy, would give them a new chance of life. White never got a chance to pursue this idea. When he went public with the results of his monkey head transplants two years after the event, it earned him only universal condemnation.
Shunned by the scientific establishment and threatened by anti-vivisectionists, he was forced to seek police protection for himself and his family and was denied funding for his work. He went from pioneer to pariah.
Despite the controversy caused by his research, he remains convinced to this day that head transplants for humans may one day be viable. And only now, 35 years after his first experiments on monkeys, does it seem that science may be about to prove him right.
Last year, researchers at University College, London, announced plans to inject the spinal cords of paralysed patients with stem cells taken from the human nose.
These are cells capable of regenerating themselves and adapting to many different purposes within the body and it is hoped they might create a 'bridge' between the disconnected ends of the spinal nerves, enabling paralysed patients to regain full control of their bodies.
If severed spinal cords can be restored in this way, perhaps head transplants might eventually become a scientific possibility - without leaving the unfortunate 'patient' permanently paralysed. Whether such operations would ever be deemed ethical is another matter - and the psychological and emotional implications simply beggar belief.
But we live in an age when French surgeons have already carried out a partial face transplant, and in which British surgeon Dr Peter Butler has been granted permission by the Royal Free Hospital in North London to perform the first complete face transplant in the near future.
Will a full head transplant be the next question for medical ethicists to consider? It's a prospect that raises many disquieting questions, not least whether our souls reside in our minds or in our bodies, and whether a person's head, living on another body, would still be the same person.
One thing's for certain. With surgical techniques improving at such a rapid rate, the issue will shortly be not whether we could carry out a human head transplant, but, much more importantly, whether we should.
No comments:
Post a Comment