Zara Whiteley lost her leg in a traffic accident
But her artificial leg allows her to run very fast
Zara is almost a science fiction vision of what a Superhuman could be
But a true Superhuman is rebuilt using flesh and blood,
not just plastic and carbon fibre.
In this programme,
we'll see a little boy called Kyle being given his hearing for the first time.
Look at attempts to treat blindness with bionics
And meet the man with the very latest in robotic limbs
But we'll also see surgeons replace missing limbs
with new ones made of real flesh and blood
Discover what it's like to live with the transplanted hand of a dead man
No, no, no.
And strangest of all, see how brain cells from a pig enabled this man to walk again.
The human body is often described as a well-oiled machine
Machines, though have one obvious advantage
when their parts fail they can easily be replaced
In a scrapyard like this you can even get them off the shelf.
In principle, it's possible to replace all the parts that make up a car
The idea of doing the same thing with the human body
as our parts wear out or are damaged by disease is seductive
But in reality our technology is finding it hard
to match the incredible complexity of the human body.
Kyle Duxbury is like any two-year old:
He loves drawing and messing about
but unlike most children of his age there's one thing he can't do.
I started to realise
I think about- when he was about nine months
because I'd, you know, look at other people's children and they'd be yabbering on;
all Kyle did really was high-pitched screams
Took him to the health office to do the hearing tests
They put him to sleep put the electrodes on his head
and the brain signals that were coming off to the computer were dead
They just turned round after they did the test and said - 'there is a big problem
and he has got a really severe hearing loss.'
You think 'no, no, he's not responding he doesn't want to hear when you want him to he
you know, try and give an excuse for every probl
that arised and 'course at the end of the day
you know, he was profoundly deaf
It still upsets me now because told him that I loved him and he never heard me for all that ti
It was quite upsetting.
'Postman Pat,
Postman Pat, Postman Pat and his black and white cat'
What normally happens when sound enters the ear is that it's transmitted
to a small spiral-shaped organ called the cochlea
The electron-microscope reveals things so sma they can't be seen with the unaided eye
Hair-like projections arranged like organ-pipes
stick out of what are known as 'hair-cells'
It's possible to isolate one and see how it reacts to Postman Pat
The vibrations are relayed by way of the auditory
nerve to the brain where they're perceived as so
But this isn't happening in Kyle's ears
In his world he sees the pictures but there's no sound.
The auditory nerve to his brain is OK
but there's damage somewhere in his cochlea
To overcome the problem
Kyle's parents have been offered a bionic replacement called a cochlea implant
He's gonna be able to hear dogs and birds
and aeroplanes, so I mean I'm hopeful
very very hopeful, that it's gonna give him
you know, the life that we want him to have
This is a human cochlea.
This spiral bit which looks a bit like a snail's shell converts sound into electrical signals
By comparison, this is the best man-made device available:
It's an electronic cochlea, and what the surgeon's
going to do is to insert this little tail here into this canal, and by doing so
it's hoped that Kyle will be able to hear ordinary sound for the very first time.
Cochlea implants have been available for some time
but putting them in can be tricky.
Underneath the skin
here we're gonna be drilling a bed in the bone to accommodate the er- the microchip in here
and we have to put that in the right place - we have to be clear of the ear so that
it doesn't interfere with the microphone
for the cochlea implant when it's eventually put into place.
There are risks with this type of operation:
The facial nerve passes dangerously close to the area where they're cutting
If it's accidentally damaged, Kyle's face could be paralysed for the rest of his life.
If he goes in and it does happen
you know, he's gonna be able to hear
but he's not gonna be able to smile.
That's the facial nerve in the distance there
and it runs through the ear from the brain to the face
and it's a risk with a lot of the operations that we do in the ear
It runs very close to the surgical approach of this particular operation
Damage to the facial nerve would give you facial nerve paralysis I V
that's a very undesirable thing, horrible deformity.
To reduce the chance of this happening
they've got a warning system:
If the surgeon gets too close to the nerve
Kyle's face will twitch;
electrodes near the muscles should detect the twitch and warn the surgeon
Once the hole has been drilled,
and the facial nerve carefully avoided
the implant is ready to be inserted.
So here's the active electrode array
and it almost sort of drops in under its own weight
not that there's very much weight - but it goes in usually pretty easily
and you just keep putting it in until
it won't go in any further, really.
Hi.
Hello there.
It's good. Yup.
No problem.
Oh, my God!
The thing went in beautifully.
Thank you, thank you very much.
It was actually very easy.
The whole thing went in first time without any difficulty whatsoever
so he'll be out in a couple of minutes I V
he has a wee bandage on his head at the moment
He's a fighter.
Let's take this away.
I'll just give you to him.
Is he fine? Is he fine?
Baby, mummy's here, mummy's here, baby, and daddy.
I'll take the tag off his hand
OK.
I can't help it.
One month later, Kyle visits the hospital again
to have his cochlea implant switched on
Lyndsey and Mark will know if their prayers have been answered
and if the operation has been a success.
You know it goes in there.
Kyle is given toys to play with while a technician
in a nearby room sets the level on his implant
so he'll be able to hear as many sound frequencies as possible.
As Kyle plays, his actions are monitored by the technician through a video link
When the levels have been set it's time to turn on the implant.
Kyle, for the first time in his life is about to hear ordinary sounds
and the moment will be registered on his face
And I'm clicking now, and you are on.
Now.
OK,
oh, lots of blinking. Stop, stop!
Look happy, try and look happy.
He'll be all right.
Is it good? Yeah?
Although his cochlea is turned on and working
Kyle isn't actually hearing words
What he's hearing is a jumble, a confusing and rather upsetting mixture of sounds.
Over the next few months
his brain has to learn what all those sounds he's hearing actually mean.
Like a baby does when it first emerges into the world
Kyle's brain starts to make new connections
It responds and adapts to the cochlea
Six months later, having heard speech for the first time in his life
Kyle is beginning to learn to speak himself.
He's got about twenty words now that he can
you know, use and understand and, you know, relate, you know, to one another
He's doing really well, I'm really chuffed with h
It's great, got a, you know, new little boy as concerned it's with his hearing
and his responses and, you know, the way he reacts to sound and
the way he listens when he walks down the street I mean, it's amazing.
Kyle's implant will stay in place for the rest of his life.
Say bye, bye.
Bye bye.
So we can treat certain types of deafness
and it had been assumed that by now
we would have plenty of other bionic ways to repair our bodies,
but it's been more complicated than we ever imagined.
Take, for example, the struggle to cure blindness with bionics.
Scientists have been trying to do for the eye
what they've done for the ear using an electronic chip
They're going to put this into the eyeball.
We see thanks to an array of about a hundred million light-sensitive cells
which lie at the back of the eye in the retina.
The whitish disc seen on the left is the end
of the optic nerve which relays signals from the retina to the brain
In some types of blindness the retinal cells are damaged
The idea is to replace the damaged cells with an electronic chip.
Chips have already been implanted into the eyes of a number of volunteers
and patients who previously could see nothing at all report seeing faint shades of light
Compared to the human retina, these chips are very crude
Some contain only about twenty cells
With an array that size, what you'd see is something like this.
It's early days, but if the experiments are successful
they may be able to increase the number of cells to one hundred, two hundred,
four, five, six, seven, maybe even a thousand cells
But the most optimistic experts agree that
it'll be decades before treatment like this will routinely available and even then
for only certain types of blindness.
Where the dreams of science fiction come closest to
what we can actually do with electronics is in the creation of the bionic arm.
Bionic arms have really come on a long way in the last few years
Even here, there's something of a mismatch between expectations and reality.
A hotel owner in Scotland has one of the most advanced artificial arms in the world
It's made of carbon fibre and is much lighter than the normal arm
Driven through gears by an electric motor its brain, so to speak, is in the upper arm.
The shoulder holds the battery.
On the inside are sensors which pick up a musc tensing in the shoulder and move the arm.
The hand and arm are covered with a latex skin
to give it grip, and it's attached to the body with straps.
To operate the arm, you have to think in a different way.
It may be that the muscles that once controlled your elbow movement
you're now using an old thumb movement.
The opening and closing of the hand could be the small finger movement.
This wrist rotation might be the movement of a thumb that you once used before.
You have to discipline yourself for about six weeks
to make sure you get the clear thinking processes in your head
otherwise it just goes bananas: It has a mind of its own.
Particular problem with this hand is you have two movements.
The hand opening and closing, and the wrist rotation.
If you don't get it right first time
It does give you movements that an ordinary prosthesis wouldn't give you:
It takes you a stage further.
It will get better but it'll take a long time to get better.
Perhaps in fifteen to twenty years something very realistic will be developed.
But the hand can't give Campbell any feedback
It's very difficult to apply pressure
to certain things - you have no sensory feedback whatsoever.
You just don't know how hard or soft
you're pressing, and the results can be.
Crushing!
The other problem experienced with the arm is
when you try to have a drink I V
not that I drink out of bottles very often
- is this pivotal movement here brings something to your mouth.
This doesn't have that pivot movement, so the result is.
I just let it go then!
Campbell's robotic arm is trying to compete
with something that took millions of years to evolve. Like our fellow primates,
we have hands that are remarkably versatile.
They let us grasp and hold objects.
This versatility also allowed us to start making simple tools
the earliest form of technology.
As our brains got larger and more sophisticated, so did our hands.
After all, skilled hands need a big brain.
It's likely that the development of manual dexterity
and the growth of intelligence went hand in hand with each other.
The result is that humans have not only the largest brains
but also the most complex hands of any animal
Our hands contain three main nerves,
two major arteries and twenty seven different bones.
Even quite simple motions involve coordinating
up to sixty different muscles.
It's this complexity that a robotic hand has to try to match.
The sense of touch is also something no artificial hand can give you.
There are two thousand five hundred nerve receptors
in each square centimetre of your fingertips.
More of your brain is devoted to controlling your hands
than any other part of your body.
The advantages of having the real thing are so great
that it's hardly surprising that some people
have opted to have one of these rather than one of these.
Matthew Scott has chosen to have a dead man's hand
in preference to a robotic one.
He lives in the outskirts of Atlantic City in the United States.
His operation took place in January 1999
but the story really starts back in the mid-eighties.
I was having a celebration with two of my friends
and we returned to the home of one of them
and he had a firecracker, and I touched the fuse to the tip of my cigarette
never expecting it to light.
This lit very quickly and the fuse started burning very fast
so all I could do was- is pull my hand away from my face
and I was standing next to a friend of mine
and I just take a couple of steps away from him before it exploded.
The explosion was so powerful, it took off his left hand.
To compensate, he had a prosthesis, or artificial hand, fitted.
He could type with it but many ordinary things he simply couldn't do.
Things such as tying my shoes or opening a door.
More times than not I've dropped things and spilled things
I was never able to pick up both my sons at the same time.
For years, Matt was coping with his life and getting by with his artificial hand.
How're you doing there, sport?
Things changed radically when they decided to take a holiday in Britain.
Whilst there, his wife bought a newspaper.
She said you're never gonna believe the article
that's in the paper, and she showed it to me
and it was about the team in Louisville preparing to do their transplant
and that they were actively looking for candidates
So immediately in my mind I said:
Well I'm a candidate and I'm going to try for this
So I read the article and read it several more times
on the aeroplane back home, and the next morning
after we got in, I made the call down to Kentucky.
As soon as I read the article I just knew our lives
were about to change for ever, right there and then
I just knew that he was gonna be the one getting that transplant I just knew it.
He was chosen by the Jewish Hospital in Louisville
to be America's first hand transplant patient.
Doctors have been transplanting hearts
and other internal organs for years, so why not a hand?
Well, a limb transplant supposedly was done in this church hundreds of years ago.
A fifteenth-century painting by Francesco Pessol
shows what is reported to have happened.
The two men standing by the bed are St. Cosmos and St. Damian.
They were in their time famous doctors
and are now the patron saints of surgeons
Accounts of their work refer to their great skill
Let's take a closer look at what's going on.
Their patient in this case is the gentleman on the bed
He had a diseased leg that no one could cure
One night he dreamed that Cosmos and Damian
amputated his leg and replaced it with the leg of a black man who'd recently died
but I wonder if there isn't another explanation for a black leg on a white man.
Doctors in those days
would not have been familiar with something
that surgeons nowadays are all too well aware of: Hyper-acute rejection.
Within a very short time, the patient's immune system
would have delivered a massive and devastating attack on what to it was a foreign bo
As a result of that attack, the leg would certainly turned black
cease to function and be rejected.
Legend has it that this man made a miraculous recovery
but for those of us that are not blessed with the help of Cosmos or Damian
the problem of rejection is a very serious one.
These days we have powerful drugs to suppress the immune system
but they can have serious side-effects.
The lead-surgeon, Warren Beiderbak, one of the very first things he said is:
I want you to understand that if you go through with this procedure I V
he was addressing the entire room I V
that this can kill you, that these drugs can potentially lead to your death.
Nevertheless, Matthew Scott decided to go ahead
and in January 1999
a surgical team prepared to carry out America's first hand transplant.
Doing a lot of thinking. Waves going round my brain
Let's not think too much, everyone, remember this is just like a...
this is like on-call, right?
This is like being on-call I'm on fire-power tonight, so
The donor hand arrived and was carefully unpacked
Altogether, eighteen surgeons were involved in the operation.
One team prepared the donor hand
while another team worked on Matt Scott's arm.
A hand transplant is tricky
because you have to connect arteries, veins, tendons and nerves
and unlike say a kidney there are three different tissues involved:
Skin, bone and muscle.
The first step was to attach the new arm
to Matthew Scott's stump using metal brackets.
With the bone secured, the next step was to work on the blood vessels.
The arteries and veins were carefully connected.
After the arteries and veins were joined,
Matthew Scott's blood started to circulate around his new hand.
Once the nerves and tendons had been connected
again using microscopes for the fine stitching involved,
the flaps of skin were sewn together.
The whole operation had taken fourteen and a half hours
Matthew Scott was going to wake up to a new left hand.
When I looked to the left I saw fingers.
It was cast and it was dressed and it was very-
but there were fingertips I V
I hadn't seen those for thirteen years, but now to look to this way and
See something there where for thirteen years
there was nothing was a wonderful feeling - it was terrific.
I remember the nurse Carrie, pulled back the sheet and said:
Look, and it was amazing, I remember crying
I remember just feeling completely overwhelmed
it was nothing that I could have prepared myself for.
Now all it was was: It it gonna work? Is it gonna take?
When I get to move it, are they gonna move?
The answer is yes, but to a limited degree.
He can open doors and tie his shoe-laces ie his shoe-laces, ed degree.
But not quite as easily as he could do with his original hand.
The new hand doesn't sweat much either
so he has to wear rubber fingertips to give him a better grip.
But all in all, he's happier now.
I could tell by looking in his eyes his anger and his frustrations were gone.
He's started to do things that he wanted to do:
He can play the drums now, he loves to practise.
He's much happier, he's much more at peace with himself
he's more balanced.
What're you doing?
The ability to do little things with such ease has just made all of our lives so much happier
There's a harmony here that- that I never knew was missing.
When it first came out of the cast and it came out of the dressings,
I could do nothing with it, Except for a few small movements.
Now I have great wrist motion, finger grip strength,
I can pick things up, I can do a lot of things
that I was not able to do before with the prosthesis: Opening the door,
tying the shoes and a lot of those little things that made life
so frustrating for me before.
So I feel better.
Grab hold of the bars
Grab the bars.
Matthew Scott is obviously content with his transplant.
But it doesn't always work out quite so well.
The world's very first hand transplant
was carried out in France in September 1998.
The patient was a man from New Zealand, Clint Hallam.
In March 2000, he was living in Perth,
Western Australia, with his wife and two children
My first thoughts when l- when I saw my hand was that
it was a miracle, and there hasn't been a day go by in the eighteen months
since the transplant that I don't still see it as a miracle.
The total join actually goes around in quite a jagged join.
It's probably only been in the past six or seven months that I've actually started to
feel uncomfortable some time with the actualdifferences in the skins.
The difficulty that I find psychologically
is that I want to be able to use my hand to do things
but it's not always possible to control it.
Now brushing my teeth is a- is a safe exercise for using my hand
but when it comes to shaving
I make sure that I've got the razor in my good hand and fully under control.
No, no, no?
Human hands are prehensile
In other words, we can oppose the thumb against the fingers with quite some strength
but Clint can't
Playing cricket with his children, he stops the ball with his new hand
but picks it up with his left hand.
One of the hard things to accept for me is that
I'm almost more handicapped with my new hand
than when I just had one and a half hands.
This is not exactly as the dream was for eight
nine, ten years, this is not happening like itdoes in the movies.
Reality really set in that progress was not as I wanted it to be,
not as I had told everybody it was going to be.
He also discovered that many people found being near a dead man's hand objectionable.
I've had people in aeroplanes- I had one lady ask to be moved to another seat
because um she didn't like the fact of sitting
next to me with- with this hand that belonged to a dead person.
A very dear friend who lives in London.
I never understood why he used to grab my hand like this
and in fact grab my wrist,
And I thought it was because he didn't want to
maybe injure the hand while I was- it was recovering.
But he used to grab my wrist simply because he didn't want to touch my hand.
To him it was quite horrific.
He has to accept that his new hand may never function any better than
it does now, and that this time he was facing the possibility
that he might lose it.
His body was starting to reject his hand.
My mid-December, the fingers ha- the fingertips had started to get red,
and I lost all sensation in the end of the fingertips.
Fortunately, sensation has started to recover
but unfortunately there are other indicators that
- that show that all is not well in Camelot. - The redness in the fingertips,
the fingernails falling off with new nails
coming underneath them, are all indicators of a serious rejection problem.
Clint's hand is being rejected by his immune system.
The immune system is a ferocious killing machin
Normally,
anything foreign which gets into our bodies is dealt with like this.
The immune system has been likened to a pack of piranhas in the ferocity
with which it attacks: Relentless and merciless.
That's how the white cells of our immune system are programmed to behave.
We have over fifty billion of these fuzzy
irregular-shaped cells constantly swarming around our bodies
and every second we make 120,000 new ones.
Look how they hunt down and destroy microbes,
and they respond this way to any foreign bodies they come across.
And that's great, except if you're having a transplant.
We can suppress it with drugs, but that carries risks
- the risks include cancer, diabetes and high blood pressure.
It's been estimated that for every ten people having a hand transplant,
after ten years one of them will be dead as a result of taking the drugs.
The American, Matthew Scott, knows that to keep his hand
he'll have to go on taking drugs
which means keeping his immune system constantly suppressed.
The common cold can be long and drawn-out,
things that would cause fever are of grave concern
because I don't have an immune system per se to fight those things off.
So there's the, you know, trade-off of the cost of the immune suppression
and the benefit of the physical outcomes.
In my opinion, I think the trade-off is well worth it.
Clint Hallam's experiences have clearly left him with mixed emotions.
So how would he advise anyone thinking of having a new hand?
My immediate reaction would be that
First they need to sit down and they need to look at their life as it is, right now.
If they have a good social life if they have a good work relationship
if they have a good family environment - if all of those things are fine
I would tell them that they really need to reconsider what they want,
because maybe it's not what they need.
To make hand transplants safer,
we'll have to find better ways to outwit our body's immune sytem.
Until we do, I think the risks outweight the benefits - after all,
you can live without a hand.
But when the transplant is one you can't live without,
such as a heart, then it's different.
If you need a new heart,
your most pressing worry won't be the side-effects of drugs
it'll be getting a heart because there simply aren't enough to go around.
Traffic accidents are still a major supplier of human organs.
But since we started wearing seat-belts, the supply has dwindled.
For every patient that gets one
there's another waiting
- an endless queue.
While we wait, machines can keep us alive,
but there's no real alternative to a heart except another heart.
When the heart starts to fail and death is inevitable there is no machine
we've yet built that can really take over.
So the wait for a donor heart becomes a poignant and desperate race against time.
Overlooking Central Park in New York is an unusual hospital unit where
the problems of shortage are starkly illustrated.
Everyone here is waiting and worrying.
Waiting for a transplant and worrying that they'll die before they get one.
We're called 'pole people'.
That's keeping me alive.
The pole's attached to us twenty four hours a day: Without that I'd be dead.
So when you see these poles coming down the hall
these are the heart transplants.
Name is Freedman, born in Brooklyn; I need a new heart.
The reason? I was on a sea-food diet; every time I see food I ate it!
They walk the endless corridors pushing their poles.
Seven times round the hospital adds up to a mile.
And they walk that mile
And then try and walk faster and faster in the hope of keeping their muscle tone
so that when they do get called for a transplant they'll be in good shape.
Peter Liuzzo waits for his transplant
With quiet desperation.
He's had a series of heart attacks, and now it's almost too late.
Four or five months ago I went to see my doctor
and when I got to his office I couldn't get out of the car
Because I was so short of breath.
The prognosis was: Don't come back 'cause we can't do anything for you.
So at that point, my son was called in and told to have me put all my affairs in order
Because I would probably go home and expire.
Each and every patient here has had to come to terms with a very harsh reality:
Their lives depend on somebody else's death.
As you sit here and I think:
Gee, in order for me to live, somebody has to die.
And I feel like I'm putting the gun in- I'm gonna shoot somebody just so I can live.
I was asked that question before they sent me here:
How do you feel about the fact that someone has to die for you to live?
I have no answer, except to say that
I'll probably pray for that person for the rest of my life.
When Peter arrived at Mount Sinai, it was winter.
Since then eight months have gone by and he still hasn't received a heart.
I can feel myself deteriorating the last few months.
We would walk for exercise and pretty soon
I was the last one in the group,
and they would get faster and I would get slower.
In September, his heart stopped and he was rushed to intensive care
where they saved his life.
By November, he was no longer able to walk
and on the evening of the 9th, the doctors came down to see him.
It was around 12.15, 12.20, like that when the doctor and nurse came in
and my first inclination was that something was wrong with my pressures
on the monitor and so on; then the nurse came around and put her hands
around my head and just started petting me.
At last, they'd found a heart And they started preparing for the transplant.
At six o'clock the following morning Peter was wheeled down to the operating theat
I'm happy, I'm thrilled, scared, all kinds of things, all at once.
A twenty one year old man had died and
his heart was already being flown to New York.
As the new heart arrives, the surgeons remove Peter's old one.
That's his heart - very enlarged and the walls are quite
His heart has become enlarged in its struggle to keep him alive.
Just how enlarged is obvious when it's compared
side by side with the new donated heart.
Finally, Peter's new heart is shocked into a regular rhythm.
So far, it looks very good.
The next couple of days is for any patient is the so-called critical period.
This is a very good start.
Peter recovered well, and two months later he's looking very different.
In the hospital, we're different shades of grey,
and we sort of get acclimated to being grey.
The first day it's shocking.
The second day, I'm a little greyer or yeah I look like I don't have any blood circulating.
And then you wake up from a heart transplant
and within a day you look in the mirror and say: Who is this?
All the wrinkles are gone, the greyness starts to disappear
your finger nails and your fingers are pink, and you're warm.
Peter is lucky.
He's got a new heart and it's transformed his life
but he knows others back at the hospital are still waiting.
One controversial way people are trying to get round the organ shortage
is by turning to animals such as pigs.
But what chance would pig tissue have against our immune system?
Animal organs are so alien that if
say, a pig's kidney were transplanted into a human
you'd expect it to be destroyed within hours.
But despite this, doctors have recently started transplanting parts of the pig
into humans with some remarkable results.
Jim Finn loves driving his Triumph sports car
around his home town of Newport, Rhode Island.
But a few years ago, life was very different.
It's damn depressing. I was contemplating suicide.
I could barely move; I had trouble walking
trouble talking, trouble using my hands
I had to crawl from room to room on my hands and knees
I couldn't walk at all; I was certain to have to use a wheelchair;
it was pretty demoralising.
Jim has Parkinson's disease.
The small group of cells in his brain which
control the smooth movement of the muscles of the body are damaged.
This left Jim at the age of 32 barely able to walk or talk.
So Jim volunteered for an experiment:
To have pig cells injected into his brain.
And the results are remarkable.
Within ninety days they could see improvement
within six months I had got rid of the cane the walker and the wheelchair.
I'm walking pretty damn good.
Obviously I still have Parkinson's disease, I still have voice problems
I still have tremor - I still shake a bit; but this is nothing compared to what
I was before the operation.
If I still had that condition I'd be dead by now.
The pig cells were injected into Jim's brain to replace his damaged cells.
The first thing they do is they drill a quarter-inch hole in your skull
I can show it to you right here.
And you're awake when they put this hole in your head
because they have to make sure they don't hit any optic nerves or anything else
that they don't want to hit. So you lie there and you joke with the doctors
which I actually did
- and they drill the hole and they put the pig cells in
and they send you home next day; all I got was a hand-shake and a band-aid!
The cells used to treat Jim came from the brain of a pig foetus.
They're using foetal cells Because they're more likely to implant and grow
Doctors have successfully treated patients like Jim using foetal cells before now
but the source was human.
Using human foetus's to repair adult brains is controversial
and it required a lot of them:
Each patient they treated needed up to eight foetuses.
There are fewer objections to using pigs.
But why doesn't the immune system attack this alien implant?
Well, firstly they're transplanting cells
not whole organs, and that produces less reaction
And they've disguised the pig cells.
Proteins on the cell surface trigger the immune response
and they've coated these with a chemical.
If the immune system doesn't recognize the cells as foreign it won't attack.
With Jim it seems to have worked
amazingly he doesn't have to take immuno-suppressive drugs.
It's early days yet
- some patients have not improved at all with this treatment
but Jim is pleased with what's happened with him.
In my case, I'm getting better every day.
Who knows where I'll wind up?
I may be able to go back to work some day
God forbid!
So will we farm animals for their hearts and kidneys?
Well, scientists have genetically modified pigs to try to do this
and like it or not, this may be the best hope for many heart-transplant patients.
We've made remarkable progress in replacing damaged parts of people.
But we've also found that something as complex as
the human body easily copied by technology
or fooled into accepting transplanted parts.
The race is now on, both to improve bionics
and to crack the complex problems of rejection.
But in this race, whichever wins we all benefit