"Nature has a wonderful ability to regenerate" "Pick a flower, and another one grows" "For all its sophistication, the human body cannot yet match a flower's ability to re-grow missing or damaged parts" "But we are getting close" "In an ideal world, if you suffered say a heart attack, your heart would not be replaced with someone else's left-over organ" "Nor with an intricate mechanical device" "Rather, you'd get a replacement heart that was as much yours as the damaged one" "In other words, you'd grow your own heart" "The human body is a highly complex mechanism, and we're only just beginning to understand how it develops and grows" "But doctors are harnessing this new knowledge to help the body repair itself" "In this programme, we'll meet a man who's grown new blood vessels to save his diseased heart" "And we'll meet a little boy who recovered spontaneously from terrible brain damage" "This is like astonishing" "Yeah, they hadn't done anything, he was just recovering himself" "For the first time, we'll see that brain cells can re-grow, and we'll discover how tissue engineers are building new body parts from scratch" "Doctors have now started to learn how to grow human tissue and how to use it to repair damage done by terrible diseases, and the worst kind of accidents" "In 1995, Penny Roberts was a keen skydiver" "That year, she and her team went to Florida for some training" "It was the 350th time that she had jumped" "As things turned out, these were the last steps Penny ever took" "we were practising slow in-place turns" "Join up, hold hands, turn three sixty and hold hands again" "Because when you're sky-diving you can't stop mid-air and say:" "Oh, just a second, I need to do that again, we had all our jumps video-ed" "At 2000 feet, the team moved apart to give themselves space to open their parachutes" "But for Penny, that's when it all went wrong" "For some reason, her main parachute didn't open properly, and when she tried to release it, it snagged on the shoulder strap" "when she opened her reserve 'chute, the two tangled together" "The cameraman chased her down in a fast spin, but all he could do was to watch the distant white tangle that was Penny falling to earth" "From when the canopy malfunctioned I think it took about three minutes to hit the ground I don't remember fear" "I remember hitting the ground and that was just a tremendous slam" "Oh, my God, Penny, Penny Stay still, don't move..." "Penny broke her right leg and her left shoulder." "She broke two ribs" "One of them punctured her left lung which filled with blood" "Her right lung collapsed" "She fractured her skull" "There are seven vertebrae in the neck;" "Penny broke five of them" "One completely shattered, and a piece of broken bone cut right through her spinal cord, paralysing all her limbs" "Penny's heart stopped three times on the way to hospital" "Advanced medical care saved her life, and with time her broken bones repaired" "But a severed spinal cord cannot be fixed" "The spinal cord is crucial if the body is to move with speed and precision" "Indeed, if it is to move at all" "It's a long rope of nervous tissue that runs down the centre of the spine, carrying signals between brain and limbs in just hundredths of a second" "Re-growing spinal cord so that people like Penny can walk again is still impossible, but recent discoveries mean there is now some h" "The human body can repair itself:" "Broken bones fuse, flesh heals and scars, but there are limits what can the body alone do about a severed spinal cord," "a blocked artery, a detached limb?" "The real experts at self-repair are salamanders" "Lizards can replace their tails, but when the need arises, salamanders can re-grow whole limbs" "Even in the real world, it takes only a matter of weeks for a salamander to replace bone, muscle, cartilage, blood vessels" " everything required for a brand new leg" "At the end of the process, the salamander's new leg has all the power and movement of the one that was lost" "There is a time in our lives when we can do the same thing" "These astonishing images are of a human embryo developing from three weeks to two months old" "Early on, it can easily grow new bones, arteries, hands and feet" "On the long journey from foetus to child, this ability gradually fades, but we don't lose it completely" "Advances in modern medicine mean that we can now tap into the superhuman powers of the embryo" "Progress is so fast that what seems impossible today could be routine by the time our children grow up" "Peter Roberts is one year old" "He's just gonna walk any day now" "Now he's started pulling himself up on the nearest object" "Sometimes my wheelchair, which is really nice" "Mummy's shoes" "Four years after her accident, Penny Roberts only dreams of walking, but she watches every move of her son" "Bit ambitious, Peter when I see Peter taking his first steps," "I just feel like any other mum would:" "I just feel pride and I watch him in amazement." "I don't relate it to me not being able to walk at all" "Because inside I'm still the same person, I'm still me, and I learned to walk and I walked around for thirty two years" "Doesn't occur to me to feel jealous" "Penny severed her spinal cord at the neck which means that messages don't get from her brain to most of her body" "Penny will not walk again unless science could help her re-grow her spinal cord" "But she has had some improvement in her condition" "Just try and keep my legs straight" "I can feel my feet now:" "I couldn't feel them just after the accident" "And also, since Peter's been born, I've found that" "I've gained a lot of strength in my arms from naturally having to hold him" "The small improvements that Penny is feeling are signs that despite everything, her body is still struggling to repair itself" "At least he's still asleep - that's convenient" "Something the body does on a small scale every minute of every day" "The body cannot afford to stop repairing itself because all day, every day, our bodies are under attack" "The sun on our face and the wind in our hair; food, drink, even exercise" " they all destroy our tissues, and we only survive because our cells continue to regenerate" "Red blood cells survive for six months, while white blood cells last just a couple of weeks" "we replace a tenth of our bone cells every year, and the fluid that fills our eye is changed fifteen times every day" "when we injure ourselves, repair starts almost immediately" "First a scab forms to protect the wound from infection" "New skin grows, the edges of the wound pull together, and within weeks everything is back to normal" "The power of healing is in itself remarkable, but now we are about to help the body do much more" "By latching onto our own powers of self-repair and boosting them, modern medicine is finally starting to re-grow parts of the body" "The first target is the heart" "Charles wilson and Roger Darke were guinea pigs for a remarkable new experiment" "Roger started suffering from severe chest pains in 1993" "He was able to keep working, but his condition got steadily worse" "I don't have to do too much where I really feel" " feels like someone squeezing my heart" "Then if I start doing..." "it turns to pain, you know?" "And if it gets worse, then I start sweating a little bit, so I don't think I'm too far away from, you know, a heart attack" "The healthy heart is fed food and oxygen by a network of blood vessels" "when these become blocked, the effect is the same as when any muscle works without oxygen:" "Severe cramp" "This sort of pain is called Angina" "It's the kind of pain that makes you think you're going to die" "Even everyday family life becomes a struggle" "It's hard when you know, Susan says you make sure that you ask Peter to carry up the trash, or make sure that you have one of the boys cut the grass" "You know, I need to get well, so that I can do the things for my own self-worth, you know, be able to do the things that I used to be able to do, take for granted that I could do" "This past year's been probably the most difficult year I've ever had" "I spent probably sixteen, seventeen hours a day in bed" "I literally was fighting depression," "I really had begun to feel like I had no value, and began to question, y'know, why am I here, what's my purpose?" "...bring us here to draw attention to God's faithfulness to his word..." "The Reverend Charles wilson has already had two heart by-pass operations" "But despite those, he still has fifteen to twenty angina attacks every day" "I went in to see the doctor and his news was not good news" "Basically he- in fact I'll use a quote from him, he says:" "You've got to sit still until technology catches up with you" "The latest techonology turned out to be a form of gene therapy that aims to grow new blood vessels around the heart" "This new treatment was so experimental that doctors were only allowed to treat patients who had no other options left:" "Patients like Roger and Charles" "The day Roger went into hospital was his 35th wedding anniversary" "If everything goes well, this could be the greatest anniversary present of all time, y'know!" "I was- been hoping for a miracle for the last five years and nothing happened so now this might be that, y'know" "we filmed Roger while he underwent the new procedure" "I'm a little concerned about putting the CCO..." "Scientists have recently discovered the gene that makes blood vessels grow" "It's busiest in the embryo when it builds all our arteries and veins" "After that, it's much less active" "In the new treatment they injected large quantities of the gene direct into the heart to encourage the growth of lots of new blood vessels" "Enough new blood vessels to save a damaged heart" "After the injections, it's all up to the human body" "Only Roger's body knows exactly where his heart needs new arteries" "Charles wilson had his operation three months before Roger and his blood vessels have had a chance to grow" "He's become one of the major success stories of the trial" "Now, ninety days out, I rarely have any angina" "Before the operation I couldn't walk from my house to the car without chest pain" "Now I'm exercising again, I walk in the afternoon, right now I'm walking one and a quarter miles ...nice, long..." "I'm so encouraged" "Mean, to be able to walk a mile and a quarter and not have chest pain:" "That's tremendous for me" "Things did not go as well for Roger Darke" "It was 6.15 when my phone rang" "I think my first thought was:" "Oh, he must want me to bring something to the hospital this morning" "And picked up the phone and I honestly..." "I don't remember," "I just remember that for a couple of words my life was changed for ever" "The morning after his operation, Roger died" "I remember even going in thinking:" "They've made a mistake, they have called the wrong family, I'm gonna get there, everything's fine, and-and it wasn't, it wasn't a mistake" "There is no sure evidence that Roger Darke's death was caused by his treatment, but the trial has been stopped while they try to find out what went wrong" "But there is one area where the creation of living tissue is already a great success" "People who are severely burned need skin grafts if they are to avoid being disfigured" "Traditionally, that skin comes from the patients themselves or from corpses" "But now, new skin can be grown by the metre" "The raw material for off-the-shelf skin comes from new-born babies" "If a baby boy is circumcised, the foreskin when grown in the laboratory can be used to grow a vast amount of living tissue" "It's important that the foreskins come from new-born babies" "The skin cells must be as young as possible so that they multiply easily and quickly to make fresh new skin" "The cells stay alive throughout the manufacturing process" "They are fed three times a day with different nutrients which encourages the different cell types to grow in layers" "The result is sheets and sheets of living skin" "In fact, a single foreskin can be grown into so much human skin that it would cover six football pitches" "But growing flat sheets of skin is far easier than growing whole body parts" "Apart from anything else, you have to get the shape right" "Even our nose and ears are complex shapes" "And the eye only works because it's a hollow ball" "when you try to copy internal body parts, it's even harder" "For instance, the heart is a pump built out of many three-dimensional bits of living tissue, all of which have to work together to respond to sudden demands, like this save from star-goalie, David Siemen" "The human body only works because its components fit together perfectly, as they do in any well-crafted machine" "I wonder how you scored past me" "Yeah, I wish, that's right" "To repair and replace damaged hearts and other organs, it is vital to grow not only to grow the right kind of tissues, but also to give them the right shape and form" "Remember this?" "In 1995, the ear on the back of the mouse hit the headlines" "It was a step forward in shaping body parts" "It actually was an implant, a plastic ear-shaped implant on the back of the mouse where it differed from other types of implants is that" "I would call it a living implant, or a plastic implant that was additionally 'seeded' with living cells" "Charles Vacanti chose to model the ear because it is such a complicated shape" "This is the plastic scaffolding, or mould in the shape of the human ear, with no cells" "So if we put this under the skin of a mouse or a human and folded the skin over, it would look exactly like it had an ear on its back" "The scaffold was made of fine strands of a completely new kind of biodegradable plastic" "what's so special about it is that when it's seeded with living cells, they stick to the fibres as they grow and take on the shape of the ear" "This is the first time that cells growing on these fibres has been recorded" "In time the cells will take over, they will generate new tissue;" "the new tissue in this case is ear cartilage, and you can see the nice contours, and it's floppy like an ear" "And the plastic is gone, so the plastic basically dissolves, and the tissue we end up with is exactly the same shape as our initial implant" "The mouse provided warmth and nourishment for the growing cells" "But the real triumph here was that living tissue had been grown in a three-dimensional form" "The next challenge was to use this same process to create a working organ" "One of the organs that scientists have first tried to make is the bladder" "It may not be the most glamorous organ, but it's a masterpiece of engineering" "Consider what it has to cope with" "The average bladder holds 40,000 litres of urine in a lifetime, and for those whose bladders fail, there is no really satisfactory substitute" "Because bladder tissue is an ingenious combination of materials" "The bladder is composed of three layers:" "An outer coat of connective tissue;" "a middle layer which is a muscular mesh and an inner layer of mucus membrane" "And this stops the urine from leaking out" "when full, a typical bladder can hold about a litre of urine, and it looks like a bloated sack" "So to grow an artificial bladder, they built a scaffold in the same shape" "And they seeded it with layer on layer of living cells we're drinking to life, we're drinking to death, we're drinking till none of our livers are left, we're wending our way down to the spirit store," "we'll drink till we just can't drink any more." "The bladder is the first whole organ ever to be grown from living tissue" "It's already been transplanted into animals, and it works" "Now the team is waiting for permission to try it in their first human" "Last orders, please!" "Many different parts of the human body are now being investigated to see if they too can be re-grown" "But what about the ultimate aim:" "The spinal cord?" "In the six months since we visited Peter and Penny," "Peter has learned to walk and Penny has been feeling some surprising changes in her body" "Before she severed her spinal cord, Penny was a nurse, so she has a clear idea of what her body should and shouldn't be able to do" "The parts of my body that weren't affected by the injury have become a lot stronger as Peter's got older and heavier" "But I've found a few muscles that I didn't know were still attached have become stronger and actually functional" "And that's just from holding Peter and balancing" "But the most exciting thing is" "That a muscle in my leg has started to twitch under voluntary control" "If I just feel it, I can feel myself twitching the muscle" "Very exciting, it's like hearing from a long-lost relative who you thought was dead" "There's only one explanation for this happening and that is that my leg is receiving a nerve impulse from my brain and that impulse has travelled down my spinal cord" "Medically, there is no explanation why this should start happening five years after my accident" "The changes that Penny is reporting are interesting, but to get her back on her feet she would need to grow new spinal cord right across the gap in her broken neck" "And until now all doctors have believed that this is impossible" "The spinal cord is an extension of the brain" "Like the brain it's a delicate mix of thousands of different cell types, every one essential" "To make new brain tissue, you'd need to grow them all" "There are now hints that this might just be possible, and they start with the salamander" "The salamander grows a new leg by getting cells at the wound site to revert to an earlier form," "the sort of cells that were around when it was an embryo" "By doing this, it is able to grow new cartilage, bone, blood vessels, muscle and skin" "Everything the salamander needs for a brand new leg" "Although we can't grow new limbs in this way, we now know that our bodies contain cells left over from when they were embryos, and they have similar remarkable abilities" "This is a three-dimensional scan of a human foetus with a clearly visible spine" "what's recently been discovered is that in the embryo the brain and the spinal cord grow from just one type of cell called a stem cell" "And stem cells might just explain why some damaged brains seem to self-repair what are you laughing at?" "What are you laughing at?" "Are you laughing at the shadow?" "When Tommy Palmer was five months old, he caught a viral infection that got into his brain - the results were devastating" "when we first got to hospital he was just lifeless, just sleeping..." "Laying in your arms laying in your arms, and if he did... wasn't feeding no, if he did wake up he was just crying all the time" "Tommy had suffered a stroke when you hear it, you think" "He's had a stroke, that's it the worst..." "He's not gonna be able to walk, he's not gonna be able to use one side of his body, his face is gonna be dropped, y'know, you think the worst." "This is Tommy's MRI scan" "Each picture represents a slice through his brain and his face" "The white patch on the right of the scan is the stroke damage" " a massive part of Tommy's brain where the cells have all been destroyed" "If an adult had a stroke that big, it would leave them permanently damaged" "Believe it or not, Tommy began to recover within days" "It was like astonishing" "Yeah, they hadn't done anything - he was just recovering himself" "They hadn't actually done anything, only looked at him" "Doctors can do nothing to fix this kind of brain damage, but Tommy's body seemed to be looking after itself" "I just wanted to see, y'know, what he does with two hands, whether he passes things from one hand to the other, what he can do with his left" "Three months after the stroke when he was assessed by a physiotherapist, the only sign of damage was a little weakness on his left hand side" "There's a good boy" "Oh, brilliant, good" "But just three months after that, Tommy is hardly affected by the stroke at all" "He's eleven months now and he's just improved" "From being basically a lump of meat in your hands, not doing nothing..." "Lump of meat!" "...to what he is now, y'know, he's just" "A lump of meat?" "Well he was, wasn't he?" "He wasn't doing anything, nothing at all" "And like to see him now is brilliant" "If you didn't know he had a stroke you wouldn't know by looking at him," "I don't believe you would - it's fantastic isn't it?" "No one understands what went on in Tommy's brain to make him recover so quickly" "Conventional wisdom says that Tommy recovered because other healthy parts of the brain took over the work normally done by the damaged part" "But there's a doctor in Boston who thinks that something much more important is going on" "Now the next thing I want you to do is turn them so that like you're going to be catching rain in the air, OK?" "Evan Snyder's passion is the brain" "He works as a neurologist in the Children's Hospital in Boston, and seeing children recover rapidly from strokes like Tommy did, convinced him that something remarkable goes on in children's brains" "Inspired by what he saw on the wards," "Snyder went looking for an explanation" "And what he found was a type of brain cell that behaved like nothing he'd ever seen before" "we could start with a single cell and then over time see a dish filled with cells that looked just like a whole brain" "It was as if we were watching a re-creation of the brain right in front of our eyes" "Dr. Snyder had seen something extraordinary:" "Neural stem cells, stem cells in the brain" "These remarkable pictures show a human stem cell dividing to become two new-born nerves:" "Brain cells actually forming" "Snyder believes that babies' brains contain lots of stem cells and that these cells help repair damage by growing new brain tissue" "The idea is very controversial so Snyder decided to see if he could repair damaged brains with his stem cells" "He started by trying to treat Shiverer Mice" "Shiverer Mice are born with extensive brain damage that makes them shiver and shake" "Snyder hoped that an injection of stem cells into the mouse's brain would repair that damage we simply took the same neural stem cells, put it into young Shiverer Mice and let the cells distribute themselves all throughout the brain," "and sure enough the cells started becoming exactly the kind of nerve cell that was needed to rescue these animals" "The mouse on the left is an untreated Shiverer Mouse" "The one on the right was treated with neural stem cells and was completely cured" "It's as if the stem cell recognised that this kind of nerve cell is missing and maybe thought to itself:" "Jeez, I guess that's the kind of cell I need to become" "So stem cells, at least in mice, can repair brain damage" "But since spinal cord is made of brain tissue, can they also repair a damaged spinal cord?" "At this point, the man who put the ear on the mouse comes back into the story" "The same sort of fibres which had been seeded with cells to form an ear will support the growth of neural stem cells" "So maybe they could be used to repair a severed spinal cord" "He tried it out on rats which had the same sort of injury as Penny" "Basically, the rats that we studied did not have a spinal cord in the middle of their back" "There was a gap of about 5 millimetres with no spinal cord in it, so there could be no transmission of information or electrical transmission from the brain down to the legs" "Fibres were twisted into a cord and seeded with neural stem cells" "This tangle of stem cells and plastic may not look like much, but it's what they used to bridge the gap in the rat's spinal cord" "And it seemed to work" "After eight weeks, the rat started to regain movement" "Y'know, it's got good muscle strength, the fur- he's grooming himself, you can see how he moves his legs" "Martin Vacanti, who works with his brother Charles, was amazed by the extent of the rat's recovery when we started this project, we were hoping to see any sign of neurological recovery such as movement of a toe maybe is what" "our initial hope was, and this was just completely unexpected" "I think we should try some swimming - is the temperature?" "Yeah that's a nice temperature" "All of the rats that had an implant with cells regained significant function" " some of them almost returned to normal movement" "This rat's left leg is still weak, but her right one is moving normally" "The control of legs and tail is better than you'd normally expect from a creature with a severed spinal cord, the same kind of injury as was suffered by Penny" "And when they examined the rat's spinal cord, they found that new tissue had, as they suspected, grown across the gap" "we have normal spinal cord above, also normal spinal cord below" "In between, in this grey area, is actual tissue-engineered spinal cord" "The rat's apparent recovery is all the more surprising because the new nerves grew across the gap completely at random" "It's a bit like cutting a telephone cable and trying to reconnect it" "You can match the red wire with the red, the blue with the blue and so on" "Or you can join the wires at random and let the central computer figure out what the new connections are" "And this is what seemed to have happened in the rats where the nerves in the spinal cord were joined at random, the brain used its phenomenal power to re-route signals" "And the rats learned to walk again" "This work is still at a very early stage, and there's no guarantee it'll work in humans" "But for the first time, we do have some of the right ingredients to repair the spinal cord:" "Human neural stem cells and the scaffolding to grow them on" "If we can apply the same technology successfully to a human, there's a possiblity that someone who was confined to a wheelchair would be able to walk normally again and to have normal sensation and normal body functions" "I'll have to sit up for that one, I think, 'cause this doesn't go behind... whoa." "Just give me a minute and I'll- let me get my balance" "Come to help you get dressed" "Have you come to help?" "If anything like this happened to Peter, I would be absolutely devastated" "Are you going to come, too?" "If people really put a lot of energy into research and we can end it with my generation and people of my son's generation won't have to go through everything I've been through" "Despite everything though, Penny won't give up the sky-diving" "Sit in front of me" "These days, Penny jumps in tandem with another skydiver" "when I went back to repeat the sky-dive, the first thing I remember was being in the plane with everybody else" "And that just felt normal" "And I remember seeing my wheelchair on the ground getting smaller and smaller, and that was brilliant, that was lovely" "when we got up to 15,000 feet" "I remember being in the door just before we exited the aircraft, and I looked down and I saw my feet and I saw the clouds below my feet, and I just thought, I thought:" "I'm back!" "Nothing seems to hold Penny back" "But is there any chance the new ideas we've seen in this programme will be ready in time to make her walk again?" "Some doctors think that it'll only be a matter of time before tissue engineering becomes a routine" "Not everyone is that optimistic" "But it is extraordinary to consider that by the time" "Peter is old enough to jump out of an aircraft, we might be able to defy nature and re-grow parts of our bodies on demand" "Fantastic." "Whee!" "Want to go and say hello to your mummy?" "Mummy"