New developments in organ transplants

Take a look at the image below

What are the key takeaways?

How surprised are you by the statistics?

Would you call this a crisis or no?

solutions

As we saw in our previous class, one solution to the problem is the following:

1 - genetically modify pig embryos

2 - implant these embryos into pigs

3 - raise these pigs

4 - harvest their organs

5 - give these organs to a human to keep them alive

6 - replace the pig organ with a human organ when one becomes available

What other solutions do you think medical scientists are working on?

Growing new human organs from cells

up to 3m28

Discussion

Have you heard the term 'stem cells' before? What are they? Why is there so much excitement around stem cell research?

Intuitively, how realistic does this approach sound as a possible solution for the organ shortage crisis?

"It is insane that we restrict this technology because of silly ethical concerns." - agree or disagree?

The term 'Frankenstein' often comes up when research like this is spoken about. Why?

3d bioprinting

3D bioprinting takes the idea of 3D printing and applies it to living tissue. Instead of printing plastic or metal, a bioprinter places living cells and biological materials layer by layer to create a three-dimensional structure. Scientists began experimenting with this idea in the early 2000s, building on earlier work in tissue engineering and conventional 3D printing. Today, researchers can print relatively simple tissues and are working towards much more complex structures such as kidneys, livers and hearts.

The potential advantages are easy to understand. In the future, doctors might be able to scan a patient's body and produce tissue designed specifically for that person. If the printer used the patient's own cells, the risk of rejection could be much lower. Bioprinting could also make organs available without waiting for a human donor. In addition, researchers can already use printed tissues as models for testing medicines, which could reduce the need for some animal experiments.

The biggest problem is complexity. A large organ contains an enormous number of cells, arranged in precise patterns. More importantly, every part of the organ needs a blood supply. Scientists can print structures containing blood vessels, but creating a dense, functioning network of tiny vessels throughout a large organ remains extremely difficult. Keeping cells alive during and after printing is another major challenge. Researchers must also prove that printed tissues remain safe and functional for many years.

3D bioprinting is therefore real science, but printing a complete replacement organ is still experimental. Researchers are currently much closer to producing tissues, patches and smaller structures than fully functioning kidneys or hearts. Some experts expect useful bioprinted tissues to become increasingly common during the 2030s, while fully printed replacement organs may take considerably longer.

Discussion

3D printing carried a lot of hype 10-15 years ago. Has this tech fulfilled its promises?

Do you think this approach is more or less realistic than growing new human organs in lab?

artificial organs and machines

One way to solve the organ shortage is to stop looking for biological organs altogether. Instead, scientists can build machines that perform some or all of the functions of a human organ. This approach is not new. One of the earliest major examples was the artificial kidney. During the 1940s, Dutch doctor Willem Kolff developed an early dialysis machine, which could remove waste from the blood of people whose kidneys had failed. Modern dialysis continues to keep hundreds of thousands of people alive.

Scientists have also developed machines for other organs. Ventricular assist devices can help a failing heart pump blood, while artificial hearts have been used in some patients. ECMO machines can temporarily perform important functions of the heart and lungs in critically ill patients. These technologies show that machines can already replace particular biological functions, at least for limited periods.

The biggest advantage is obvious: machines do not depend on human donors. A patient does not have to

wait for a compatible organ to become available. Artificial devices can also be manufactured, tested and improved rather than depending on chance.

However, the human body is extremely complicated. A natural organ does far more than its most obvious job. The kidneys, for example, do not simply remove waste; they help control blood pressure, minerals, fluids and hormone production. A machine that performs only some of these functions may keep a person alive but cannot completely reproduce a healthy kidney.

For this reason, artificial organs are already realistic for some situations but much less realistic as permanent replacements for complex organs. Researchers are increasingly combining machines with living cells to create “bioartificial” organs. In the next 10–20 years, we are likely to see more sophisticated devices that temporarily replace or support organs. Fully artificial replacements for organs such as kidneys or livers, however, are unlikely to become routine until scientists can reproduce much more of their natural functions.

Discussion

We mentioned dialysis yesterday. What is it? How does it work?

The difficulties are becoming fairly predictable - organs are complicated and we need to make sure they are safe. Do you think people should be allowed to take greater risks with their own health if they are suffering with life-threatening illnesses?

There is also a lot of talk about who should be prioritised when it comes to receiving an organ:

a) people with money?

b) people with healthier lifestyles?

c) younger people?

What are your thoughts on this?

Out of the three methods we've seen today, which do you think will become mainstream in the next 100 years?