In a day and age that ears are being grown on the backs of mice and livers being produced in labs, could we be very well on the road to financing organ replacement and extended life through continuous organ replacement?
In the movie, Repo: A Genetic Opera this very issue is the plot.
In the not-so-distant future, a worldwide epidemic of organ failures devastates the planet. Out of the tragedy, a savior emerges: GeneCo, a biotech company that offers organ transplants…for a price. Those who miss their payments are scheduled for repossession and hunted by the villainous Repo Men. In a world where surgery addicts are hooked on painkilling drugs and murder is sanctioned by law, a sheltered young girl searches for the cure to her own rare disease as well as information about her family’s mysterious history. After being sucked into the haunting world of GeneCo, she is unable to turn back, as all of her questions will be answered at the wildly anticipated spectacular event: The Genetic Opera.
In a article from BBC News you can find the following:
The scientist who grew a human ear on the back of a mouse has suggested it may one day be possible to “grow” a liver.
US researchers say the prospect of artificial livers has been brought closer because they have worked out how to grow deep networks of blood vessels – which has not been done before.
The potential new source of livers for transplants was welcomed by campaigners as a way of closing the gap between the number of organs needed and those available.
In the UK, there are only around 100 people waiting for a liver transplant, but the British Liver Trust said many people died before they reached the list.
However experts have warned the laboratory-based research is a long way from working livers.
In 1997 Dr Jay Vacanti grew a human ear from cartilage cells the back of a mouse, causing outrage among animal rights and pro-life groups.
Now Dr Vacanti, a transplant surgeon at Massachusetts General Hospital in Boston and Jeffrey Borenstein, micro-engineering expert at the nearby Draper Lab are looking at growing more complex tissues.
Scientists had believed it was not possible to grow anything more complex than simple tissues, such as thin sections of knee cartilage and skin because of problems growing the blood vessel networks.
To do this, they use a “frame” made of a biodegradable plastic.
This is immersed in a solution of the patient’s cells, then in a nutrient solution.
As the cells multiply and link together, the frame dissolves, leaving a piece of cartilage which survives because oxygen and nutrients from surrounding fluids feed into the cells.
But in thicker tissues, the nutrients are unable to get past the first few cell layers and need an internal blood supply to survive.
The technique developed by the researchers involves copying the blood vessel network of a real liver and using 3D computer modelling and machining to mimic its construction.
To copy the structure, they injected a liquid plastic into the blood vessels of a liver, wait for it to solidify and dissolve the liver tissue, leaving a solid cast of the organ’s blood vessels.
They can then take “measure up” and feed data into a computer to create a 3D model of a liver’s blood supply.
This model is then “sliced up” on the computer into horizontal layers, which can be used to make a silicon mould.
Biodegradable plastic is then poured into the mould to make enough slices that can be sandwiched together using pressure and heat, to create a scaffold for a whole liver.
The scaffold then has to be injected with at least seven types of cells that make up the solid part of the liver.
A solution of endothelial cells, which normally line blood vessels, then has to be pumped into the empty channels in the frame where they stick to the walls.
These can then be grown in a nutrient to form a network of blood vessels within the scaffold which again dissolves over a few months.
If each step of this process works, it would result in a functioning liver.
But blood vessel networks grown this way have so far been tested in rats, with no leakage or obstruction of the blood flow.
Linda Griffith, a tissue engineer at MIT, said one of the main problems of the idea would be getting all the right cell types to grow in the right places.
She told New Scientist magazine, which sets out the research: “In just a gram of liver, you have around 100 million cells and it’d be very hard to position each and every one.
Larry Hench, a tissue engineer at Imperial College, London added: “Currently, there’s no way of keeping these implants sterile, and no one is really looking at that.”
“If we can’t sort this problem out, we could be stuck with lab-based solutions we can’t use.”
Nigel Hughes, chief executive of the British Liver Trust, told BBC News Online: “We know that the demand for livers is going to outstrip supply.
“We hope to see all of this biotech science come to fruition.”
Now it seems that the liver is more than just a Scientific dream.
Many people need new organs, but the numbers that are available don’t begin to meet the demand. At Wake Forest University an effort to solve that problem – at least for livers – is bearing fruit.
The team of researchers, led by Shay Stoker, a professor of regenerative medicine, and Pedro Batista, a doctor of pharmacy, has used human liver cells to successfully grow a small version of the organ.
The liver is just large enough to be transplanted into a rat. That’s the next step, says Batista – to see if the new liver takes over the function of one that isn’t functioning.
To build a liver, the researchers took an animal liver and removed the liver cells with a mild detergent, leaving only the skeleton. The liver skeleton is a scaffolding of tissue, rather than bone, but it still offers a way for the cells to organize themselves. They then placed liver progenitor cells and cells that line blood vessels. When the cells were provided with nutrients, they grew into a small liver.
Batista says the livers will be implanted in rats that are given cirrhosis. In humans cirrhosis is often caused by alcoholism. (In rats, it is induced by other methods). The rodent experiments will also help show whether the new livers are safe to use.
If successful, the work will show that it is possible to engineer a human liver from relatively few cells, which could be harvested from the patient who needs one before being grown.
There are many billions of cells in a liver, and even in rat-sized livers there are hundreds of millions. Batista says his team’s technique can grow a liver from only a few million cells, or about four milliliters worth.
To make a fully functional human liver they would need to regenerate about a pound of liver tissue. A full liver weighs about three pounds, but even a portion of a liver can provide enough function while it regenerates naturally. The engineered livers are a long way from that – right now they weigh about 0.2 ounces.
One thing that makes livers interesting, Batista says, is that more than any other organ they can regenerate. That makes the regenerative medicine simpler. But livers are not simple organs – there are no less than four different vascular systems in them.
The new livers do have limitations. They don’t have a system of bile ducts, only the cells that process the toxins. As time goes on they could get better at regenerating those systems, Batista says.
Ultimately, regenerating livers could be used to treat liver disease and supplement -or even replace — transplants.
“There are 16,000 people waiting for a liver,” Batista said. “Maybe 5,000 will get one, and 10-20% of those waiting will die.”
Batista says his own interest in livers comes from being a pharmacist. In drug development and use, the liver is one of the most important organs as it processes the toxins and drugs people ingest. “We’re always interested in livers as pharmacists,” he said.
So my question is….. When are the loans for organs and the repossessions of said organs going to start?