Hi, I'm Erika Matunis, and we're standing in the laboratory where
my research team studies stem cells.
[MUSIC]
My lab uses the fruit fly, Drosophila melanogaster,
to study stem cells.
And to explain stem cells,
let's take a look over here in the toy box.
Stem cells are amazing cells because when they divide
they give rise to all of the differentiated cell types in our
bodies.
Like this blue block is a stem cell and
every tissue contains just a few stem cells.
So, those will be the blue blocks.
When the stem cells divide, they make daughters that look pretty
similar to the stem cells, but have a really different fate.
So what the daughter cells are going to do is make more and
more progeny in the tissue and
fill that tissue up with differentiating cells.
And so all of these other blocks are going to be
the differentiating cells in our tissue.
So the stem cells are critical for regenerating whole tissue.
And if something happens and all the stem cells are eliminated,
say by disease.
Then you won't have enough differentiating cells in
the tissue anymore either.
So that's why stem cells are so important.
And now, I want to tell you about some of our work.
I'm gonna use these magnets to depict a tissue.
Tissues have boundaries.
And I'm gonna use this math toy to depict the stem cells.
So if these little blue muffins are our stem cells,
there's just a few of them in a tissue.
And a really important thing about stem cells is that
they are controlled by their neighbors, so
they have managers.
So I'm gonna use these red muffins to depict the niche
cells and they're actually gonna manage what the stem cells do.
So they communicate, they send signals to the stem cells, and
make sure that the stem cells stay alive,
divide appropriately, make the right kinda tissue.
So these stem cells are going to be capable of
making all the right kinds of differentiated cells
that the tissue needs to function normally.
So what we've found is that if you eliminate the stem cells
from the tissue, as you could probably guess, all these
differentiating cells are also gonna disappear from the tissue.
But what was unexpected is that we saw that the niche cells, who
are normally just the managers and don't actually build
the tissue, take on the role of the stem cells.
And so they change and first, they divide,
and there turns out to be more of these niche cells.
And it turns out that when there are enough of them
they actually split up and make a whole new niche.
So instead of just having one niche in a tissue you can have
two or even three and they're not really normal.
They fill up with more stem cells and
the stem cells start to divide.
But you get all kinds of differentiating cells that
are really confused now in the tissue and
it doesn't function properly at all.
And instead, it grows to what appears to be a tumor.
So it turns out that having these extra stem cell niches
that are full of stem cells that are active in the tissue is
really not good for the tissue.
And the tissue gets misshapen and
it's not functioning properly.
And what really intrigues us is how really we can go from
a situation where there's just, One stem
cell niche that's functioning normally to extra niches.
How do these extra stem cell niches actually show
up in the tissue?
Does the first one get really big and split into two and
seed a new niche and recruit more stem cells?
This is not understood, but
having the right number of niches and
stem cells in all of our adult tissues is really critical.
Because when it's misregulated, that can lead to cancer.
So this is what we'd like to figure out next.
Targeting cancer stem cells through understanding how their
niches work is the key to cancer therapy.
And we are really excited to be a part of that.
[MUSIC]