28 July 2011

ARTIFICIAL ORGANS - We make human spare parts

In a small lab on the ninth floor in the Royal Free Hospital in Hampstead, a technician is watching a vial of clear liquid spin. It's an inexpensive and unremarkable-looking liquid but it can be transformed into a human artery, vein, heart valve, tear duct or trachea. It might in the future be used to make human hearts, bladders, lungs, larynxes, noses, penises, breasts, ears - or most other parts of the human body you can think of. It is the liquid, if you like, of life.

This liquid was developed by Alex Seifalian, professor of nanotechnology and regenerative medicine at UCL Medical School. It is, to get technical, a nanocomposite polymer called - wait for it - polyhedral oligomeric silsesquioxane-poly (carbonate-urea) urethane, POSS-PCU for short. To get less technical, it is a liquid plastic that sets solid when it is heated up or cooled down and contains billions of tiny holes. Earlier this month it was used in an incredible bit of surgery, when a patient in Sweden had a section of his windpipe replaced with a piece built from his own stem cells and the professor's polymer.
This was the first time anyone in the world had received an organ made in a lab. It was a lifesaving operation and it marked the beginning of a new era in medical science. Using the technology, humans can start growing new and replacement body parts to order.
Professor Seifalian works in a small office a few yards from the lab. Aged 53, he has walnut skin and slightly bushy eyebrows. Long nights have given him the beginnings of bloodhound eyebags. But he is seldom far away from breaking into a slightly roguish laugh.
An expert and enthusiast, he has a clear vision of how the work of his small team could change the world. "A lot of organs in the future can be just made in the lab and transplanted," he says. "They will be available 'on-the-shelf'. People will be able to order them, add the patient's stem cell … and put it in the patient. If someone comes along here and says 'make us this', we can spend time and make it. Initially it is difficult to make but once we've made one we can make hundreds."
It sounds like the stuff of science fiction, a comparison he bears with equanimity. "We're not creating humans," he says. "We make human spare parts. We're not making the car, we make the engine, or a piece that has broken."
Seifalian, who began his career as a nuclear physicist, and his multidisciplinary team work at the point where physics and biology, surgery and science, collide. For some time they have made smaller synthetic bits for bodies, such as arteries and tear ducts.
The "spare part" that took Seifalian to the fore of the scientific world this month was a 36-year-old Eritrean man's trachea. Seifalian and his team were given just two weeks by a Swedish team to build him a new one and save the man's life.
It was an incredibly exciting time. "We were working day and night in the lab," says Seifalian. "I live across the road and I was going home to sleep just a few hours a night. My PhD student was sleeping here. My post-doc was here all the time, making the polymer."
Their work was so effective that Seifalian says he now has six more tracheas on order. It is not only the lifesaving aspects of his polymer that are thrilling. There are plenty of cosmetic surgeons, I suggest, who would love to be able to offer their patients new body parts.
Indeed there are. Seifalian says he has just been to a meeting where he has been discussing the possibility of using his polymer for breast reconstructions. For post-cancer mastectomy patients, he suggests, using his polymer would enable more effective breast reconstruction than the fat cells currently used.
But there's a cosmetic purpose, too. The professor delves into a desk drawer and pulls out two breast implants. Both are full of silicone but one is encased in his polymer, the other in the regular material used. He squeezes them, to demonstrate how much stronger his version is - virtually impossible to burst inside an augmented breast.
Is there anything he can't envisage making? "A brain I cannot make," he says. "And the liver is a complex organ, so we won't be able to make that. But the heart is possible. Not tomorrow, but maybe in three years' time."
Seifalian's polymer is incredibly cheap to produce (for around £50 he can make 500ml - enough to make two tracheas) and the possibilities for its use seem endless. It must be an extraordinary feeling, I say. He seems tongue-tied. "It's an amazing feeling … to do something … as a scientist and an academic …" He tails off. But not for long.
"My wife always complains," he laughs. "She says 'how much money will you get?' But it's not a money thing… it's just to see that someone got better from your work."

Why synthetic?

Hundreds of thousands of patients require organ donations every year. Those who survive must take drugs for life to suppress their immune system. Since it is seeded with a patient's own stem cells, Professor Seifalian's polymer is not rejected by the body.
The operation
The first transplant of a fully synthetic organ took place on July 9 at the Karolinska Hospital in Sweden.
The patient was Andemarian Telesenbet Beyene, who had advanced cancer of the trachea, which would have killed him. The medical team was led by Professor Paolo Macchiarini.
To build a new trachea, Macchiarini sent Professor Seifalian a 3D CT-scan of his patient's chest. Seifalian commissioned a glass-blower to make a perfect model of the damaged organ. This model was then dipped into liquid polymer, which set to form a plastic mould of the trachea, covered in millions of tiny holes in which new cells could grow.
The mould was sent to Sweden and placed in a bioreactor with nutrients and stem cells from the patient's bone marrow. It was rotated slowly at body temperature. As it rotated, the stem cells attached to the plastic mould and began to form themselves into a new trachea. After two days a new organ was ready. It was lined with cells from the inside of the patient's nose, and implanted in his body during long surgery. He has made a full recovery.

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