and, just like getting over a cold,

you could heal your wounds faster?

Today, if we have an operation or an accident,

we're in the hospital for weeks,

and often left with scars and painful side effects

of our inability to regenerate or regrow healthy, uninjured organs.

I work to create materials

that instruct our immune system to give us the signals to grow new tissues.

Just like vaccines instruct our body to fight disease,

we could instead instruct our immune system

to build tissues and more quickly heal wounds.

Now, regrowing body parts out of nowhere might seem like magic,

but there are several organisms that can achieve this feat.

Some lizards can regrow their tails,

the humble salamander can completely regenerate their arm,

and even us mere humans can regrow our liver

after losing more than half of its original mass.

To make this magic a bit closer to reality,

I'm investigating how our body can heal wounds and build tissue

through instructions from the immune system.

From a scrape on your knee to that annoying sinus infection,

our immune system defends our body from danger.

I'm an immunologist,

and by using what I know about our body's defense system,

I was able to identify key players

in our fight to build back our cuts and bruises.

When looking at materials that are currently being tested

for their abilities to help regrow muscle,

our team noticed that after treating an injured muscle with these materials,

there was a large number of immune cells

in that material and the surrounding muscle.

So in this case,

instead of the immune cells rushing off towards infection to fight bacteria,

they're rushing toward an injury.

I discovered a specific type of immune cell,

the helper T cell,

was present inside that material that I implanted

and absolutely critical for wound healing.

Now, just like when you were a kid and you'd break your pencil

and try and tape it back together again,

we can heal,

but it might not be in the most functional way,

and we'll get a scar.

So if we don't have these helper T cells,

instead of healthy muscle,

our muscle develops fat cells inside of it,

and if there's fat in our muscle, it isn't as strong.

Now, using our immune system,

our body could grow back without these scars

and look like what it was before we were even injured.

I'm working to create materials

that give us the signals to build new tissue

by changing the immune response.

We know that any time a material is implanted in our body,

the immune system will respond to it.

This ranges from pacemakers to insulin pumps

to the materials that engineers are using to try and build new tissue.

So when I place that material, or scaffold, in the body,

the immune system creates a small environment of cells and proteins

that can change the way that our stem cells behave.

Now, just like the weather affects our daily activities,

like going for a run

or staying inside and binge-watching an entire TV show on Netflix,

the immune environment of a scaffold

affects the way that our stem cells grow and develop.

If we have the wrong signals,

say the Netflix signals,

we get fat cells instead of muscle.

These scaffolds are made of a variety of different things,

from plastics to naturally derived materials,

nanofibers of varying thicknesses,

sponges that are more or less porous,

gels of different stiffnesses.

And researchers can even make the materials

release different signals over time.

So in other words, we can orchestrate this Broadway show of cells

by giving them the correct stage, cues and props

that can be changed for different tissues,

just like a producer would change the set

for "Les Mis" versus "Little Shop of Horrors."

I'm combining specific types of signals

that mimic how our body responds to injury to help us regenerate.

In the future, we could see a scar-proof band-aid,

a moldable muscle filler or even a wound-healing vaccine.

Now, we aren't going to wake up tomorrow and be able to heal like Wolverine.

Probably not next Tuesday, either.

But with these advances,

and working with our immune system to help build tissue and heal wounds,

we could begin seeing products on the market

that work with our body's defense system to help us regenerate,

and maybe one day be able to keep pace with a salamander.

Thank you.

(Applause)