even hearts.

In fact, at the moment there are some people walking around with lab-grown bladders.

But this is rare.

In the U.S., over 80 percent of transplanted organs come from the deceased.

The rest are donated by the living — except for a small number that are grown in laboratories.

However, this could all change fairly soon.

In the not too distant future, you might have a spare heart, kidney or liver grown for you

in a lab.

And someday there could be warehouses full of new organs.

So how close are we to farming human body parts?

[TRACE] Last year, there was a record number of organ transplants in the United States

- over 30 thousand!.

Which sounds like a lot, but the waiting list for organ donation is over 100-thousand.

There just aren't enough organs to go around!

[DR.

ANTHONY ATALA] In a 20-year period, the actual number of patients on the transplant list

has gone up six-fold, 600 percent...So, really, there's a dire need for organs for patients.

At the moment, the main way to get an organ is from a donor, but what if we could just

cook up our own from scratch?

[DR.

ANTHONY ATALA] We have placed lab-grown organs into patients already, we have a number of

tissues we have implanted into patients.

And the goal is to increase the number of patients that can benefit from these technologies.

[TRACE] And Dr Atala knows.

He led the team that developed the first lab-grown organ to be transplanted into a human in 2006.

It was a bladder which, to be fair, is a pretty simple structure.

But what about organs that are more complex?

[TODD McDEVITT]: Each of them actually, even the ones that may look simple, have their

unique challenges to them

[DR. ANTHONY ATALA] there are some things which are harder to make than others.

For example, there's a level of complexity as we look at tissues with flat structures

such as skin being the least complex.

They're flat, mostly one major cell type.

Tubular structures, like blood vessels, are the second level of complexity.

Hollow non-tubular organs, like the stomach, the bladder, are the third level of complexity.

And by far the most complex are the solid organs, like the heart, the lung, the kidney,

the liver.

[TODD McDEVITT] As they get more complex in terms of the numbers of cells involved and

the structural features, the complexity of those.

The brain is certainly one that many people, I think, would say is among the list of higher

tissues or organs to try and create.

[TRACE] Now, there are scientists who are working on growing brains in the lab, but

so far they've only produced miniature, partially functioning brains, about the size

of a piece of popcorn.But these aren't being grown to implant into humans, they're being

used for medical testing.

Like, seeing how the Zika virus affects the human brain.

Now, how are scientists doing all this?

Well, growing organs and organ tissue comes down to our good friend, the stem cell.

Stem cells are the basis of all the cells in our body.

They're like children, and can grow up to be anything.

[DR.

ANTHONY ATALA] To grow a tissue, or an organ, one of the very first challenges to overcome

is really how to get the cells to grow.

[TODD McDEVITT] The pluripotent cell has the potential, at the earliest state, to turn

into heart and liver and lung.

Not just the tissue, but all the different cell types: the heart muscle cells, the blood

vessel cells--all of those necessary cells that you need to form a complex tissue or

organ.

[TRACE] Our old friend the stem cell is powerful.

It's already being used to grow things like skin and tracheas

[TODD McDEVITT] One thing we're interested in is using the power of stem cells to try

and grow or coax the cells to form the tissues, largely on their own so what are the minimal

cues, the minimal information we need to provide to let them do something they're already

capable of doing.

[TRACE] But we want to know about growing a complete organ, or let's say, an entire

farm of organs and that's where things get a little crazy.

Right now, scientists are creating organs and body parts using 3D printers.

They make a biocompatible plastic scaffold, stems cells are placed onto it, and then they

pop that whole thing into an incubator that mimics the conditions of the human body.

[DR.

ANTHONY ATALA] Through the 3D printers we're really trying many different types of tissues.

We use, basically, your typical, imaging software program that's available at every major

hospital where you can really three-dimensionally configure what the organ really looks like

and then to develop our own software program that can then download the information from

an x-ray, then you can print a structure to fit that specific defect in that patient

[TRACE] While we can print simple structures, solid organs are more complex - engineers

need to figure out how to connect blood vessels and tissues within the same organ.

Which ain't easy.

[DR.

ANTHONY ATALA] The most difficult organs to create are the solid organs.

But the future really is can we actually create structure so we can put in,to either augment,

or replace these solid organs.

[TRACE] Then we have to overcome another huge obstacle.

Even if we can make these organs, how can we produce them on a large scale and farm

them?

How do we meet the demand of thousands and thousands of patients.

It's a process that could to take decades.

[TODD McDEVITT] So, realistically speaking, I think that widespread manufacturing and

availability of large organs that are produced in a lab or reactor setting: we're still a

long ways away because of some of the challenges that we face in growing them reproducibly

to that size.

Where I see in the shorter-term success--five, ten year period--is that, can we make small

pieces of them?

Can we make lots of them?

[DR.

ANTHONY ATALA] In terms of solid organs, it's still gonna be a while.

In terms of the less complex organs, such as flat, tubular and hollow non-tubular organs,

we're already there.

We're putting these into patients now.

[TODD McDEVITT] One of the big ones of the moment is the manufacturing.

Can you make enough of this and can you make it repeatedly enough so that it's deemed

safe?

You can't just make it once and it be very different the next time.

That's not acceptable.

[TRACE] So we've come a long way.

But seeing row upon row of hearts, livers and kidneys being grown and delivered to you

via drone?

That's still the stuff of sci-fi for sure.

So take care of that liver.

Or don't.

Who am i, your dad?

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