Towards artificial organs

The field of medicine is constantly advancing. It is a theme that I revisit time and again, because these breakthroughs could be commonplace a decade or so down the road. Just remember that diseases that can easily be cured today were fatal just a few decades ago. In the same way, a few decades from now, there could be a cure or vaccine for diseases such as AIDS/HIV and even some forms of cancer.

Transplant and implantation surgery is one field where exciting things are happening almost every month.

The future is already happening. Take the story of an Eritrean patient identified as ‘Mr. Beyene’. Doctors discovered a golf-ball-size tumour growing into his windpipe. Despite surgery and radiation, it kept growing. In the spring of 2011, when Mr. Beyene came to Sweden to see another doctor, he was practically out of options.

But the doctor, Paolo Macchiarini, at the Karolinska Institute had a radical idea. He wanted to make Beyene a new windpipe, out of plastic and his own cells. Implanting such a “bio-artificial” organ would be a first-of-its-kind procedure for the field of regenerative medicine, which for decades has been promising a future of ready-made replacement organs - livers, kidneys, even hearts - built in the laboratory.

Researchers such as Dr. Macchiarini are building organs with a different approach, using the body’s cells and letting the body itself do most of the work. This field is also known as tissue engineering.

The possibilities are endless, given that some scientists and engineers are also working on entirely artificial structures to replace damaged body parts and organs. Simple artificial parts such as knee caps are already available. But only a few organs have been made and transplanted. Most of them are relatively simple, hollow ones - like bladders and Mr. Beyene’s windpipe, which was implanted in June 2011.

Tissue

In Beyene’s case, an exact copy of his windpipe was made from a porous, fibrous plastic, which was then seeded with stem cells harvested from his bone marrow. After just a day and a half in a bioreactor - a kind of incubator in which the windpipe was spun, rotisserie-style, in a nutrient solution - the implant was stitched into Beyene, replacing his cancerous windpipe. Fifteen months after the groundbreaking surgery, Beyene, 39, is tumor-free and breathing normally.

He is back in Sweden with his wife and two small children, including a one-year-old boy whom he had thought he would never get to know. The best thing about the surgery is that the windpipe contains only his own cells, so he does not need to take drugs to suppress his immune system to ward off rejection.

The good news is that scientists around the world are using similar techniques with the aim of building more complex organs.

At Wake Forest University in North Carolina, for example, where the bioartificail bladders were developed, researchers are working on the kidney, liver and more. Labs in China and the Netherlands are working on artificial blood and blood vessels.

You may argue that artificial hearts, heart-lung machines and other such machines have been around for decades. But the fact remains that they are only machines. Tissue engineers want to produce something that is far more human. They are experimenting with making organs with cells, blood vessels and nerves to become a living, functioning part of the body. Some want to go even further - to harness the body’s repair mechanisms to remake a damaged organ on its own.

The likes of ‘Bionic Woman’ as featured in the hit 80s TV series could become a possibility within our own lifetime and a few generations hence, they will be common. However, “Tissue engineers” admit that the work they are doing is experimental and costly, and that the creation of complex organs is at least a few decades off.

Stem cells transplants are controversial, because most research is done on embroyonic stem cells. (Human stem cells are part of the body’s system for building and repairing itself.

They are able to become specialised cells specific to particular tissues or organs). But what about the use of adult cells that can still become another type of cell? Such stem cells can be obtained from adult bone marrow, thereby avoiding or lessening any controversy. Researchers are making use of advances in knowledge of such stem cells, that can be transformed into types that are specific to tissues like liver or lung.

Scientists are also learning more about the natural scaffolds of organs, or extracellular matrix - intricate three-dimensional webs of fibrous proteins and other compounds that keep the various kinds of cells in their proper positions and help them communicate. Labs around the world are now experimenting with these ‘scaffolds’ with the goal of using the natural ‘scaffolds’ themselves to build new organs.

Breakthrough

An even more astounding breakthrough was reported on Wednesday, also from Sweden. Two Swedish women could be able to give birth using the wombs in which they were carried, doctors say, hailing the world's first mother-to-daughter uterus transplants.

The weekend procedures were completed by more than 10 surgeons at Sweden's University of Gothenburg. The surgeons said they won’t consider it successful unless the women give birth to healthy children.

This shows that we don’t always have to turn towards artificial organs or even deceased donors. Some organs can be taken from living donors, but the range and options are limited. And it is not always easy to find deceased people whose organs are in a pristine condition for transplantation. This is why research on artificial organs must be continued.

As I have said in this column on previous occasions, work is progressing apace to build better artificial lungs, hearts, bones and even eyes. There already are some rudimentary camera-sensor combinations that already help the blind to make out vague black and white shapes.

While this is recommended only for people who had lost their sight after quite some time and not for those who are blind from birth, there is no doubt that full-colour vision for the blind would be achievable in a few decades, in the light of advances in miniaturisation and nano-engineering, biophysics, neuro sciences, IC chips and cameras. That would be the holy grail of artificial implants. We are familiar with the debate that have arisen with the use of carbon fibre blades as a substitute for legs by South African double amputee Oscar Pistorius, with some arguing that the blades give him an undue advantage over able-bodies athletes who have to use their “natural” legs. Could there be a time in which artificial organs could be better than the body’s own “natural” ones? For a start, artificial ones hardly break down, do not age and are not struck down by disease. Will these bionic people be superior than the rest of us ? Will only the super-rich be able to afford them, leaving others to perish if they do not get a new organ? It will thus be a very interesting debate from a moral and ethical point of view as well.

One thing is clear. Progress in this field is inevitable and unstoppable. But the results should permeate to the wider society, just like discoveries such as penicillin and vaccination did. Only then will these achievements become true breakthroughs.