( applause )
And thanks everybody for coming out on a cool November evening.
What I'd like to do today is just talk a little bit about
stem cells and the heart and
implications for in the way of regenerative medicine.
So we'll start out a little bit by talking about the burden of
heart disease.
to what are stem cells. From there, move on to how our
understanding of cardiac biology
cells to change in a dish to has changed, how we can get stem
And then about cardiac become heart cells.
center here on campus. regenerative medicine and the
today, but I'd like it to be So we've got a bit to cover
So if you have questions as we interactive.
them. go, pleI don't know. to ask
Tom, can you turn down the light
little brighter, or is that in frontimpossible?een is a
Or could I do it, if I was smart
( inaudible ) ( laughter )?
While Tom is testing himself
So I just want to start because I am a cardiologist here at UW.
That's great. You don't have to turn it down
too low.
campus, and also have a basic I am a research lab.here on
The focus of my research is understanding heart disease and
defining new treatments for it. And part of that is in education
and making sure that everyone's aware of really how big a
problem heart disease is. It remains the number one cause
of death in the United States.
U.S. live with one or more forms About 71 million people in the
It causes about 37% of all of cardiovascular disease.
And it's estimated in direct deaths in this country.
to be about $403.1 billion. So this is a big public health
problem.
in this pie graph over here is The majority of the problem here
disease. related to coronary artery
up in the coronary arteries. That's the cholesterol building
well as a range of other That can cause heart attacks, as
But tonight, I'll focus a little cardiovascular diseases here.
disease and what it means to bit about coronary artery
therapy may help with that. hOn this slide, I just give youl
some images.
may or may not be able to see These are MRhere.ges that you
I'll try and point out. Let's see, does that show up?
That doesn't show up. So there's--
Well, you can't really see it.
in the heart in a normal heart, so I'll just have to describe it
to you. All the walls come in in the
pumping chamber of the heart
and symmetrically to eject the left ventricle, equally
And what happens with the heart attack is you lose part of that
wall. Here's a heart that had a heart
attack and there's a part of the
Without a pointer, I can't wall not moving.
Maybe I'll use this. really show you that.
black area is the wall. SIt's should be moving in, ands
it's not. And so part of the heart muscle
stops working after a heart attack.
And it becomes scar tissue. So the obvious question is, can
we address that problem with new
heart muscle. apSo that's where the issue ofed
stem cells come in. And first, I'll spend a little
time describing what stem cells are and how we understand them.
A simple definition of a stem cell indicates that it has the
ability to divide or
indefinite periods of time, even self-replicate for, really,
organism. thIt can differentiate intoan
various specialized cell types
it can potentially grow into under the right conditions and
such as heart cells and nerve very mature cells.lized cells,
There are a variety of different
Embryonic stem cells are one types of stem cells.
They're isolated from the pre-implantation blastocyst.
That is after the sperm and egg unite to fertilize and form the
zygote. That begins to divide.
It forms the cystic structure called the blastocyst, which is
sort of floating before it
And if those inner cell mass implants in the uterus.
blastocyst, they can then be cells are isolated from the
conditions, originally on a cfeeder layer of cells that
maintain them as
cells that are pluripotent, in undifferentiated non-specialized
the different cell types in the that they cabody.e rise to all
And they can grow indefinitely
They can also be grown up as in culture.
of cells. So that's what embryonic stems
cells are.
the mouse. They were first isolated from
were described by Martin and And mouse embryonic stem cells
And really set the groundwork for a revolution in biology with
engineered mice models really helping us understand the
function of individual genes by loss of function, knocking out a
gene and seeing what happened to
Or gain a function experiments, adding a gene and seeing what
happened to the mouse phenotype and the mouse cells.
So this was a major advance for biology.
And it's created a whole new
And even back in 1981, folks tool for research.
useful to have human embryonic thought it would be potentially
But as you can see, it wasn't easy to get the human embryonic
stem cells. Jamie Thomson here was the first
to make a step closer to that when he isolated embryonic stem
cells from non-human primates from the rhesus and marmoset.
And that was published in 1995
But ultimately the interest really ramped up when Jamie
successfully isolated embryonic stem cells from surplus
In Vitro Fertilization embryos
That is embryos that were created for couples undergoing
treatment for infertility, and
created in a tissue culture in the procesdish.y embryos were
Some of which were implanted in the mother and went on to bear
children. The rest were cryo-preserved
indefinitely, potentially for future use.
But with informed consent, Jamie
donor's consent, and isolate the was able to get these with the
Here, a colony is shown growing on a fetal layer of mass
embryonic fibroblasts, which
this field. hAnd the latest excitement, asin
Tom suggested is related to a new form of stem cell.
This is something called induced
And really, there have been several labs working hard on
this. Perhaps one of the leading labs
is from Japan.
this work working in mouse and Yamanaka and colleagues started
Where they took fibroblasts, using mouse fibroblasts.
terminally differentiated cell. So we start out in development
as a zygote, a very blank slate cell that then progressively
specializes.
of development is as this cell And typically, our understanding
it can't go backwards and get geless specialized with normal,
development.
that if you expressed the appropriate combination of genes
in very specialized mouse fibroblast cells, that you can
reverse their clock and reprogram them so they become
pluripotent.
into all different cell types in In other words, they can grow
cells. the body, like embryonic stem
these really are pluripotent And the most recent proof that
pluripotent cells were injected into a mouse blastocyst in a
study done by Yamanaka. And in that blastocyst, they
incorporated and they became a
schematically here after chimeric mouse, shown
So you've got these cells growing into all the different
cell types in the mouse.
the germ cells and they can do And then they can even get in
So they can form mice from this single induced pluripotent stem
cell. So they are truly pluripotent in
the case of the mouse.
People didn't really think it Awould be that easy to turn the.
clock back on cells, to get them
And this is recent work, really starting to come out just last
year. And the most recent paper was
earlier this year.
because just this week we heard about human induced pluripotent
cells that were isolated both by
Yamanaka group, where they Jamie Thomson here and the
particular way to transform the cells and get human cells into
these induced pluripotent stem
regenerative medicine cells thaapplications.rtant for
The figure just shows that in Jamie Thomson's work, they were
able to differentiate these cells into a variety of
different lineages. When they formed teratoma tumor
in mouse cells, they allowed the
differentiate into neural-like cells to spontaneously
structures, and into gut-like structuresstructures.ilage-like
Just a selection of different tissues that can form.
Again, supporting the idea that these are truly pluripotent stem
cells.
there are also stem cells in And that's not to forget that
cells, or progenitor cells, are aa little more specialized.m
Probably the best description of
blood system in the adulhematopoietic stem cell.the
It's present in our bone marrow,
what's called a progenitor that can give rise to a variety of
different cell types. If it's a lymphoid progenitor,
it can give rise to lymphocytes,
If it's a myeloid progenitor, it specific blood cells.
of blood cells. canAnd this is sort of thesets
hierarchy of development of this
quite important for us. blAnd this has been, really,y
appreciated for a few decades,
stem cells that are able to that the self-renew. contains
They undergo what's called
So if this cell divides, one asymmetrical division.
the other starts to specialize a cell remains a stem cell, and
They are multipotent, but they're not pluripotent.
That means they can differentiate into many cell
types, but they can't differentiate into the full
gamut of cell types present in
And the most rigorous test the human.
hematopoietic stem cell and reconstitute a blood system in
an animal or a human. So really what the hematopoietic
stem cells and more recent
tools to find stem cells in technolother tissues. us are
We've known about them in blood for a number of years.
But only really in the last decade or so have we started to
appreciate stem cells in other
And that's because we've had tissues.
those cells. tools that allow us to identify
standard histology, looking at Otherwise, when we do the
really stand out as anything tissues, the stem cells don't
And it's only by using special.
various specialized proteins on athose cells, as well as gene
expression studies that we can
as well as better techniques in tmicroscopy to allow us to look
at the tissues, and better ways to isolate the cells.
And that's important because
these tools have impacted we'll gcardiac biology.out how
So now we'll start focusing a little bit on the heart and
where I focus most of my effort and energy.
And one of the dogmas of cardiac
heart responds to injury. bAnd a common injury is a hearte
attack or a myocardial
you with the movie, which didn't infarction, as I tried to show
But what happens with the myocardial infarction is a scar
forms.
heart that's had a myocardial And here iinfarction. through a
And the blue is the area of scar.
All that blue tissue is dead
They are fibroblasts, but there are no red muscle cells.
So this part of the heart won't contract.
So obviously, the larger that is, the bigger the problem is.
It turns out this scar puts stress on the rest of the heart,
causing it to sort of work
And in the long haul, that overtime.
call remodel, get bigger, cadilate, and go on to heartwe
failure.
are associated with loss of Sfunctional contracting hearte
muscle cells. And so we typically thought that
once you lose the cells, they're
And that was the dogma I grew up gone for good.
largely still the dogma being with itaught today.ool and
But when people have more recently been looking at things
a little more closely, they found that things don't quite
add up that way.
meticulous and count the number of heart cells in a rat heart,
there are about 23 million
But if you also look at the rate myocytes.
undergoing programmed cell that those myocytes are
apoptosis, about 1.34 million cells die every month.
So if you then take that into consideration and look at 20
months, you'd think there'd really be no heart left.
But it turns out there are some fewer myocytes, but really not
that many fewer.
difference? How are we making up for the
cells lost via programmed cell
Then others have looked for cell death?
It's been very controversial, divihard to find.eart.
But in diseased hearts, they can
dividing. So maybe the heart isn't sort of
fixed after you're born, and
cells. there is the ability to get new
came with work earlier in 2000, Anwhere people did sort ofne
interesting work in heart transplant patients.
Something that modern medicine
that really have no options with has created to help patients
But it's also provided a a failing heart.
you transplant a female heart, research tool, and that is, if
into a male recipient, males females have two X chromosomes,
And if you look at that female have XY.
ingrafted, if the patient dies heart later on after it's been
they got these autopsy samples, you find out that in the female
heart, it should be XX, there are Y chromosomes.
Where did those Y chromosomes come from?
Is there some population of cells getting into that heart
that then are forming heart cells?
So these have been sort of clues
is a little more complicated, and maybe it has some ability to
repair itself.
have identified adult stem cells And at the same time, others
including skin, liver, fat, skeletal muscle, the GI tract,
and so forth. So really, the breakthrough
paper came pretty recently, 2003.
We've been studying the heart for a long time.
But just in 2003, really some definitive work was done that
provided evidence that there are
So there is a population of adult stem cells, shown here as
these small cells with a rim of green around them.
I'm not sure if you can see that
But that green is identified too well.
a protein called c-kit, which is with an antibody that recognizes
cells. particularly present on stem
of other experiments to support the idea that these were stemy
cells in the heart. So this really is a fundamental
change in our understanding of
all sorts of new potential cardiac biology and gives us
So the good news is that there avenues to treat heart disease.
call them progenitor cells are cardiac stem or you could
They're self-renewing. identified in the heart.
they can grow from a single In other wordcell.y can grow and
They're clonogenic. And they're multipotent.
That is, they can grow into heart muscle cells, but they can
also grow into blood vessel cells.
Having muscle without the blood vessels to supply it
wouldn't be too useful. So these cells can do all that.
So regenerate heart tissue, pretty encouraging.
So the heart, like we also found
terminally differentiated post-mitotic, so that means very
specialized cells that can't
But it's not simply only those divide anymore.
There's a hidden population of cells.
ability to repair the heart. stem cells that have some
those endogenous stem cells holds promise for treatment for
a variety of heart disease. And perhaps some of the most
striking findings were produced by this work in zebrafish where
Mark Keating and colleagues took
the tip of the heart. aThey just cut it off and threwf
it out to see what would happen.
formed there initially, a blood And it turns clot.hat a big scar
But over time, that was replaced, and the heart totally
regenerated in the zebrafish. So zebrafish can totally repair
their heart after an insult like
The bad news is we can't. So most of the insults that we
are faced with in adult cardiology, stem cells that are
endogenously present aren't able
wouldn't be seeing it to takeclinically., or we
Why is that?
become dysfunctional with aging. It may be that adult stem cells
heart failure, the bone marrow-derived stem cells aren't
working so well.
risk factors for And interestingly, many of the
a cholesterol build-up in the atherarteries are inverselyords,
correlated with the levels of circulating stem cells.
In other words, if your cholesterol is high, and your
bad cholesterol is particularly high, it knocks back the stem
cells in the circulation. It's sort of a potentially a
one-two punch.
stem cells in our hearts, but the way they are, they're really
not taking care of many of the
So how can we get around that insultsand treat that?ed with.
And I think that's where the
some of these stem cells and the idea of harnessing the power of
will be helpful. tools of regenerative medicine
or not these stem cells can actually form heart muscle and
some of the work we've done in
And that work has looked at the differentiation or
specialization of embryonic stem
using a system where we take the cells into cardio-myocytes,
remove them from the specialized undifferentiated cells and
undifferentiated, form clumps of conditions that maintain them
embryoid bodies and then plate cells in suspension called
spontaneously differentiate. them down, and they
little cover slips and look in We can then plate them on our
And we can see contracting there.
I don't know if you can see that cells.
But there are cells spontaneously contracting.
They give us a not-too-subtle clue that heart cells have
developed.
pattern. They develop in sort of a random
doesn't recapitulate formation This embryoid body formation
Rather, it's a spontaneous of an embryo.
embryoid bodies have these process, and some of the
So we've then gone on to study beating areas and some don't.
( inaudible ) thosI will do that.ls--
It's not important
( inaudible ) I will do that on another slide.
I can read it on my computer
( laughter ) screen.
Tom would have to do that, ( inaudible )
But maybe he could. becaus( inaudible )n, beyond me.
No, I'll fill in blanks where the red shows up.
But on this slide, don't worry
So what this shows is a schematic diagram where we can
take an electro physiologic apparatus, so an amplifier, and
put an electrode, a micro-electrode, into the cells,
and then measure their
And why might we want to do electrithat?ctivity.
One of the hallmarks of different types of heart cells
is their electrical signature.
organ. Our heart is an electrical
triggers the contraction. So different parts of the heart
have different electrical, what we call action potentials.
So the pacemaker region of the
node, sort of has this slow upstroke action potential and
this slow what we call
But that's quite different than action potentials in the atrium,
the upper chambers of the heart,
chambers of the heart, which and the ventricles, the lower
phase. have a much longer plateau
hearts have different types of So the four chambers of our
And that's sort of a nice signature, because it's made up
of the opening, closing and activity of really, dozens, if
not a hundred different electrical ion channels and
transporters. It gives us sort of a
fingerprint of the cell type. And so when we took our
electrode and measured some of
electrical activity from the these action potentials, or
that there are a variety of different electrical signals.
There are nodal-like action potentials, suggesting that
nodal-type cardio-myocytes can
stem cells. devThere are more atrial-likenic
action potentials, more ventricular-like.
So this is just a general proof of principle that the embryonic
stem cells can form all different types of
cardio-myocytes, which may be useful for different
applications. If you've got a problem with a
ventricle, you'd like to put
If you need a biopacemaker, you might want to think about more
nodal-like cells, for example.
be important to have these stem Ancells beating in a dish isht
something to do with cardiac
Now I have to get you a little drug safety.
This is a schematic of an electrocardiogram, and one QRS
complex, which is essentially one heart beat.
And it turns out that from the
activity to the end, which is called the QT interval, depends
on how long the electrical
ventricular muscle. So a longer QT means a longer
action potential. And so we can measure an action
potential in these heart cells. And we can see if a drug makes
that action potential longer. So why am I telling you all
this? It turns out that it's
important, because there are
rhythms that can be induced by certain potentially lethal heart
Not as part of their planned certain drugs.
side effect. effect, but as sort of a bad
patient actually admitted to UW Hospital, now more than a decade
ago, who came in and was taking an antihistamine called
Hismanal, and had fainted in
And she got brought into the church.
with an electrocardiogram. ICU, and they monitored her here
line so they could measure her Also put in an intra-arterial
You can see the electrical blood pressure here.
And a long QT interval is here, which is a sign that the action
potential is long.
rhythm here that's called And whTorsades de Pointes.heart
It goes very fast and you can see the blood pressure goes down
to nothing. So if this wouldn't have
spontaneously broken, this would
didn't happen in the hospital. have been a lethal event, if it
other studies, led to the withdrawal of this drug from the
market. It's also led to the withdrawal
of several other drugs, and is
With all new drugs coming through development, they're
screened for this potential side
But there aren't great models to effect.
So potentially using screen for that.
stem cell-derived cardio-myocytes may provide
a useful tool to help with drug safety, as well as other aspects
of drug development.
about cardiac regenerative So now let's talk a little bit
now with that. medicine and where we are right
think is an extremely exciting So regenerative medicine, I
It's really largely new concepts.
And it's rapidly growing. It explores, not only the use of
stem cells and their derivatives
also looks at the ability to to repair damaged tissues, but
own reparative properties using small molecules, for example, to
turn on endogenous stem cells or
to repair itself. to So it's a broad area thatbody
encompasses a lot of different
But if we're going to think about cell therapy, we have to
really take our time and think
from the research lab to about the various steps to get
And the first step, really, is patients.
population. tAnd develop, if we're going tol
do tissue engineering, making pieces of tissue that will then
implant into a patient. We have to really develop the
appropriate materials to do that.
And then test their properties
culture dish. And then use them in animal
models of disease, understanding
animal models to deliver them, how best to put them in the
animals from rejecting them as understanding how to prevent the
Ultimately, we'd like to see in the animal models that they're
effective and that they can ingraft, integrate into the host
tissue. Improve the function of the host
tissue and cause the disease to get better.
But at the same time, equally and maybe more important, they
have to be safe.
infectious agents. We don't want to bring along
formed. WeAnd we don't want any otherors
potential problems, such as arrhythmias to come up.
And then, ultimately these will get into human trials.
So there's a bit of work to do
most of these cell-based before we get to patients with
For cardiac cell repair, and applications.
of heart disease, are associated many of the most prevalent forms
cardio-myocytes. with a loss of function
about getting new cells in So it is appealing to think
Whether it's coronary artery there.
infarction, causing the loss of a big piece of the heart, heart
failure with loss of functioning
are due do the loss of heart heart cells, certain arrhythmias
And maybe engineering new valves muscle.
therapies and tissue could take advantage of new cell
A variety of different cell sources have been considered for
this. And many have already been
tested, whether it's stem cells from the blood, so-called
endothelial precursor cells,
skeletal muscle, from fat. mesenchymal stem cells from
about embryonic stem cells, and also stem cells even from the
heart itself. It's also important to think
about your source of donor
self, or whether they come from cells,non-self sources.e from
So we call that autologous if it's from self.
So if you give some of your own bone marrow and they purify that
to transplant into a heart. Or endothelial precursor cells
are isolated from your blood, skeletal myoblasts from your
muscle biopsy.
the new induced pluripotent Maycells from a skin sample.t is
Or cells isolated from your heart or cord blood cells.
But maybe allogeneic cells will be a potentially important
source. Right now, the embryonic stem
cells represent an allogeneic source.
Mesenchymal stem cells are
baby cord blood from other folks another allogeneic source, or
source of cells. would be allogeneic or non-self
here, and I'm sorry about that. This is a slide that really got
us going down this road quickly.
really, in early 2000 and 2001, by Peiro Anversa's lab and Don
Orlic's lab, where they did sort
They took blood stem cells. So they isolated stem cells out
of the bone marrow, isolated the
And it was from a mouse that stem cell population there.
fluorescent protein. expresses a protein called green
positive, which means they're green under the appropriate
illumination. They transplanted them to a
mouse that they tied off the
had a heart attack. Then they saw what those cells
did.
there are a bunch of green And here you barely can see,
But in the same range of tissue, cells.
cardiac protein called myosin, there's also staining for a
those transplanted cells became suheart tissue in the area of or
injury and are regrowing heart
So that got everybody pretty muscle.
take bone marrow-derived stem exccells and regenerate heartld
muscle. So that really got this field
jump started. But it hasn't been without some
controversy.
have said that bone marrow stem A cocells do not regenerate labs
infarcted myocardium. And this was, again, published
in a fairly prominent journal,
And so this has been an area of some controversy as to what the
cells do. We, in our lab, used another
cell population.
cells, and transplanting them Andinto a mouse heart model.stem
And again, green cells have a reporter protein to tell us
where the cells came from.
is an area of regenerated heart And hard tomuscle.re, but this
And the red is an antibody to what's called smooth muscle
actin.
vessels you may be able to see. And this is regenerated bloodd
vessel and heart tissue here. We think that transplanting
embryonic stem cells can help the heart.
And what we, and many other labs, have found is that
transplanting these stem cells
impact on the heart, in that if you look, these are what are
called M-mode echocardiograms.
attack, this is a particular What you see is after a heart
chamber is of the mouse heart. measurement of how big the
End Diastolic dimension for the It's calleaficionados.entricular
It gets bigger after a heart
That is, the heart dilates attack.
myocardial infarction. after a heart attack, after
blunt that, what we call And transplanting the stem cells
So the heart doesn't dilate as remodeling of the heart.
Likewise, the contraction of the much after the heart attack.
shortening, gets much less, heartbecause you're losingional
functioning heart muscle. And if we transplanted the stem
cells, that decrease in fractional shortening is
blunted.
helps the heart, in that it blunts the remodeling and also
improves the fractional shortening, or contractile
properties of the heart.
How does it do it? Two good things.
were thinking that it was all regenerational repair to help
the tired heart.
heart muscle. But over time, it's become clear
that there are many, many potential mechanisms.
And maybe these cells were only really secreting factors that
helped the heart repair itself. Or maybe they're fusing with
other cells in the heart to change their function.
Maybe it's just stabilizing that
stretching and putting the heart scar so it doesn't keep
Maybe it's turning on the cell in mechanical disadvantage.
those cells that we thought could never divide, to divideg
again.
connective tissue in the heart Changing the way that the
Reducing that programmed cell death or drop out heart cells.
Turning on endogenous stem
Forming new blood vessels. cells.
possibilities that are being They're really many
are helping the tired heart. investigated, that ultimately
which are the most important It's really up in the air as to
powerful. But I think this gives you an
idea that there are many
develop over time to treat heart potential avenues that will
fundamentally new insights. But it hasn't slowed us from
getting into clinical trials. And these are, this is a list
that I know no one will be able to read.
And I just show it to you to
have been done since this discovery in 2001, up to 2006,
these are the completed phase 1 and phase 2 trials looking at
cell therapy in the heart.
sort of get some of these trials This is really unprecedented to
patients, at this quick tempo. into patients, these cells into
are primarily designed to look And phase 1 and phase 2 trials
less at efficacy. The phase 2 trials start to look
at how beneficial this therapy
So the conclusion from the is.
we can see, putting primarily inbone marrow cells into humant
hearts is safe. These are autologous cells, so
they're taken from the patient, his or herself and put back into
the patient, mostly after a myocardial infarction.
But there's a variety here of different approaches here.
It seems to be safe.
trials that have been done to look and see if it's more than
safe, if it actually helps. Here's a German trial called the
Repair AMI Trial. They took patients after a
myocardial infarction who had an
the heart. impairment in the contraction of
three to seven days after that They transplanted these cells
And they looked at how well the contractile function of the
heart improved after that.
here, that there was an improvement in the ejection
fraction, or the contracting
And they also looked at clinical properties of the heart.
In other words, how many end points.
myocardial infarction or needed to have a blood vessel openedt
again.
cell therapy. ThAnd now there's follow-up toe
this original study.
of follow-up. At the meeting I was at earlier
this month, now we're at two
And these beneficial effects years follow-up.
However, if you go a little further north to Norway, and you
do apparently the same thing in a trial called the ASTAMI trial,
where they randomized 100 patients after a myocardial
infarction who had angioplasty, percutaneous intervention.
Then they got these bone marrow cells on day six.
They looked at left ventricular function by a wide variety of
measurements. And the long story short is they
didn't see any beneficial effect, either on ejection
fraction or on clinical end points.
So that has left us with some finger pointing going on,
talking about whose cells are better than whose and how you
isolate the cells.
and a number of articles trying to understand how preparing the
cells after you isolate them
their biologic activity. from the bone marrow may impact
the details of some of these I'm not going to go through all
say, there are some fundamental disagreements on the right way
to prepare the cells, and whether that impacts--
Yes?
result, how do you know that the >> When you get a negative
heart are actually integrated in cells that you put into the
So the question is if you get a negative result, how do
you even know you got the cells where you want them, and whether
they're alive and functioning?
challenges with human trials. SoIt's hard to answer some oftal
those very logical, basic biological questions.
And I think, again, that's one
studies are so important, ofreally, to refine ourmal
understanding.
when we put in these cells, we The best we can tell is that
specifically, because in both of are targeting them pretty
catheter. And that catheter went into thea
coronary artery, where the
They blew up a balloon, so the infarction was.
of the heart, but only could be cshot down the coronary arteryt
into the infarct bed. So they could only go into the
tissue where there had
So they should go that previously been an infarction.
The question is did they stay dithere?n.
Do the stay alive?
trials. AnThere's no easy way to trackan
that. In part, because one of the
reasons this has been able to get to clinical trials so
quickly is that if you take cells out of a patient, the
patient's own cells, you just clean them up a little bit, and
put them back in, there's less
If you take those cells out, chance for things going wrong.
approach so you can see where they are and get reporters, then
you've monkeyed with them,
quality control. you've got to do much more
trials, they're sort of the Sofirst gee-whiz approach.l
So your question is good, and we
Yes? don't know.
the changes in contractility >> Do you have baseline data on
You know, I went over that. I glossed over that quickly.
That's another great question.
stem cells, with optimum medical It turns out that even without
attacks, ejection fraction tends care, with medium sized heart
attack if you get on the right to get better after the heart
What they're arguing is that medicines and good medical care.
improvement with the cell there's therapy.greater
So they've compared it to placebo, which is squirting just
the media the cells were growing
And both improved relative to right after the heart attack.
But the improvement is even greater with the cells.
Yes?
ejection fraction? >> What was the change in
You know, the absolute change was shown here about 2% to
2-1/2%. >> What was the question?
Change in ejection fraction.
change in ejection fraction? >> I'm sorry, so what is the
is it clinically significant? So a normal ejection fraction in
patients is generally greater than 50% or 60%.
And so a 2-1/2% improvement on
would argue is of borderline ejection fraction some people
It's of statistical clinsignificance.ance.
In other words, it seems to be a
But will that impact clinical clearoutcome?nce.
People have debated that. But in this trial, they did make
some measurements of clinical end points, suggesting it could
improve how patients did, at
cells, in Germany. least in this trial, with their
debate as far as the right cell So preparation and the right and
patient population, as well,
Some of the earlier trials that will maintain benefit.
have very big heart attacks. studied patients that didn't
if you're looking at patients Andwith a small heart attack,hat
they're prognosis, outlook, is
They're going to do well, regardless of cells or no cells.
So it's sort of silly to study
So you really need patients that cells in those folks.
a significantly weakened heart, that are going to need some
additional help.
being studied. So only now are those patients
to understand this biology, the Even thtrials continue. trying
And we have been reluctant to get involved, initially.
But now we couldn't hold back anymore.
So we're participating in a trial here.
This trial looks at patient population.
It's a little different.
intractable angina. So they have blockages in their
coronary arteries that we can't fix with angioplasty, with the
balloons, with stents, we can't treat with medicines any more.
They have chronic pain, chronic symptoms with any activity.
So they're really at the end of what we can do with medical
therapy.
done, can't do it again. Bypass surgery has usually been
referred to as no-option And so these are sometimes
And so one of the hypotheses is if these cells can help grow new
blood vessels, and get blood to the muscle that's not getting
enough blood that you might improve the angina.
You might improve the clinical
So there's a trial that Amish Raval is the local principal
investigator. It's a multi-centered trial.
Douglas Losordo at Northwestern is the overall trial principal
investigator. Where we isolate from blood
CD34+ cells.
expressed on endothelial This is a particular protein
that we can then use magnetic pbeads, pull them out of thed
blood after they're mobilized using this apharesis technique.
And then purify them. Then we take the patient to the
catheterization lab and use a fancy technique of
electroanatomical mapping called
the function of the heart, how NOGA, where we can both look at
electrical activity, and it's squeezing, as well as the
that aren't squeezing so well ibut are still alive based on
their electrical activity, which
the heart not getting enough is a hallmark for that area of
That's shown here in this red area on this map.
And the black dots are where we can inject cells.
So you make multiple injections of cells in this area of heart
muscle that's sort of alive, but
getting new blood vessels to barely alive, in the hopes of
patient's angina. That's an ongoing trial that's
still enrolling patients. We obviously don't know the
outcome of that.
give us a dose of reality as far But I think it's important to
developments to take, really, to as how long we can expect these
And how much it's actually going get into mainstream medicine.
I think it's useful to look at to cost.
comparison. So from getting an idea of a
target for a drug until FDA approval of a drug, in the range
of 10-15 years for most drugs.
in the range of $800 million per And in current dollars, costing
A pretty big investment in time drugand money.ge.
So thinking that we can get the complexity of cells into
broad clinical applications over
without much investment is a remarkably short time period
Maybe cells are more like devices, such as the implantable
cardiodefibrillator, ICD. That story, first described in
1969 in an animal experiment in Baltimore.
It wasn't really put into a patient experimentally until
1980. And the first FDA approved
application was in 1986.
from the proof of concept Suntil patient application.
What about stem cells themselves?
Well the whole idea of stem cells isn't all that novel.
Blood stem cells, or hematopoietic stem cells,
were really first conceived of in the late 1940s and
early '50s, largely based on
happened after Hiroshima our understanding of what
And the radiation sickness and and Nagasaki.
in those folks. losAnd so the concept of aions
stem cell renewing blood in the bone marrow grew out of that.
And the first successful bone marrow transplant was done in
1956, in identical twins, for leukemia.
But it really wasn't successful in an unrelated donor until
1973. It's become more broadly
available to patients, and there
and so forth, and it's a major is now banking of bone marrow,
Again, that took from, really, clinical application.
there. the '50s until the '80s to get
promise with cellular therapies and regenerative medicine for
the heart, but it's not going to
Stem cells has also brought up happen tomorrow.
the stem cells come from. This is largely focused on human
embryonic stem cells since
blastocyst or embryo. And those embryos are destroyed.
And so this raises questions
time. What is the definition of life?
And other questions, such as
cell nuclear transfer. cloning, also called somatic
potentially a attractive way for That's been suggested to be
cloning. what's called therapeutic
are outlawed in most parts of Things likethe world.ive cloning
Also concerns about exploiting
to be able to generate these oocyte donors, or egg donors,
And then questions such as cell lines.
If you treat an animal brain chimeric animals.
have you really created there? with human brain cells, what
and you have animal and human Ifgenes mixed in reproduction.e
A clear ethical concern.
discussion, thoughtful debate, So that's led to a lot of
Ultimately some guidelines have andemerged from a variety ofons.
sources.
here. The National Academy of Sciences
has produced guidelines for human embryonic stem cell
research that you can look at.
Stem Cell Research has also The Iprovided guidelines. for
Both have suggested the formation of oversight
committees, an ESCRO committee, which we have here at the
University of Wisconsin, as well
Standing for Embryonic Stem Cell as other institutions have them.
be sure that only ethically Resapproved applications are, to
underway at the university. And different countries have
come up with different ways to
And again, what happens in the provide oversight for this.
national policy. United States, as far as our
policy, as per the Web sites. And it states that federal funds
will be set aside to explore the
cell research, with sort of the pcoda here that federal funds
will not support the further
cell research. destruction of embryos for ES
lines, that were derived before So scienAugust 9, 2001.existing
So a compromise position by the Bush Administration.
And the funding of more translational, that means
getting from the basic research lab to the clinical arena is not
well developed yet. And that's in contrast to drug
development, right? The pharmaceutical industry has
really developed this structure to get a compound that may be
useful through clinical trials
Many of the ideas come from basic researchers, but there's
big cost, big funding that comes
industry. There is no such thing yet for
cellular based therapy and
And so this is one of the growing pains that we have to
work with right now with this novel approach.
The federal policy has been a little complicated with the
inability to use newly derived
So some of the states have seen fit to address this issue.
And it's ranged from really trying to facilitate research
using stem cells and embryonic
The biggest example is stem cells.
Proposition 71, a couple years California, which passed
year of taxpayer money for ten ago, that took $300 million a
this research in the state of years, or California. to support
Obviously, they're pretty excited about it.
And if you compare that to the
in 2006 on stem cell research, amount of money the NIH spent
the $300 million in California, you can see where the field
is not quite level since
the country. this was spread throughout
initiatives to support stem cell Other states have provided
passed legislation prohibiting research, while some states have
So it's a varying playing field out there in the U.S. right now.
To facilitate our work in stem
here on campus, we formed a cells ancenter recently.edicine
And our mission is, "To advance the science of stem cell biology
and foster the clinical breakthroughs in regenerative
medicine through faculty
and education." And one of the things that wet
realize has been very lacking here on campus is a good way to
communicate, both within campus and outside of campus.
We really need to get better
That's important for you, too, communication.
that can provide some of the because we have a Web site here
here, maybe not. background, maybe I'll get it up
network. No, I've got to log in to the
provides information for But we have a Web site that
information about stem cells and patients and also general
We want to improve the basic the researchers here on campus.
basic research to clinical research, work to translate this
challenges in bioethics and also treatments, understand the
policy that can really allow develop appropriate public
forward. this new area of therapy to move
together across disciplines. We want to get people working
getting complex. Because as you can tell, this is
drugs as complex. YouThat's a single molecule.ping
If you think about the
the tens of thousands of complexity of cells and really,
sync there. diIt's not a simple process.in
So we want to get groups from chemistry, from engineering, the
basic biologists, the clinicians, all working
together. And also we're working hard to
expand our educational
So just a few things that hopefully you'll be able to take
home. I have to say heart disease is
still a big problem here. It's our number one killer.
And we really are in desperate
Some of the new tools and approaches that have come
through basic research have allowed us to understand that
there actually are stem cells in
And I think that's going to provide all sorts of new avenues
for therapy.
cells that researchers have discovered and are working with:
embryonic, different adult
now the newest kid on the block cthe induced pluripotent stem
cells.
or divide indefinitely in These stem cculture. self-renew
They can form the highly-specialized cell types
that are necessary to repair or regenerate a heart, or other
organs, for that matter.
medicine is really a rapidly And cardiac regenerative
We're developing new treatments. expanding field.
going to be years before many of But it's a long road and it's
mainstream. tAnd I think this wille
revolutionize our treatment approaches for a broad variety
of diseases over the coming decades.
And all the work that I presented was the work of many
folks working together. And I just show you some of
their names.
answer any questions. With t( applause )op and try and
Thank you.
But there's also other options >> You referred to embryonic.
( inaudible ) >> The question is,
I mentioned embryonic stem cells
And there are other options. in the talk.
cells attractive or not So what attractive.onic stem
The embryonic stem cell, right
standard for a pluripotent stem now, is scell.f the gold
That is, it can form every cell type in the body.
Most of the adult stem cells
repertoire. So they can only form a certain
collection of cells.
cell from the heart or the Typically, if you take a stem
heart or brain. The other advantage of embryonic
stem cells is that they're
to renew. So you can grow them potentially
indefinitely in culture, which
amounts of cells, which can grow means you can grow up vast
Whereas the adult stem cells into vast amounts of tissue.
They stop dividing over time in undergculture.ence.
So you know, obviously, there's ranges for both of them.
But the attraction with the embryonic stem cells has been
that they're the most versatile cell, and if you grow up the
most of them, and they do best
cell sources. in cBut you know, there areother
obviously limitations.
of embryonic stem cells. You don't have unlimited numbers
of the use of human embryos. They're difficult to get because
consideration and the ethical Sconcerns with that.l
So there are pluses and minuses.
( inaudible ) Response to these cells, which
came from different individuals?
challenges if you're going to use these cell therapy.
We talked a little bit about
in and allogeneic. autologous, self-cells put back
matter, sorry, I'm repeating the So the question was, does it
answer. But the question is how does
this impact, if you use embryonic stem cells from one
embryo that's not matched to the
And that is a concern. patient.
that those cells would be rejected unless we get clever
and find ways to allow those
something that's called cells timmune-tolerance.o induce
We know from work with solid
kidney transplantation, heart otransplantation, there's been,
ongoing research to understand
you can take those cells. howThe easiest way is to giveso
immunosuppressive drugs.
do that with transplanted And we knoworgans.been able to
That has some shortcomings, because the immunomodulating
drugs can have some side effects
So I think it will take ways to modify the stem cells, perhaps
to make them better able to be
example, one strategy is well, tolerated, as well as, for
lot of cell therapy and repair a if you're going to really do a
also need to give them a new heart in a patient, maybe you
So you can put in cells and reconstitute their immune system
with bone marrow cells derived
cell line. from that same embryonic stem
theoretical approaches. >> Theoretically, your own cells
would be preferential.
excitement with these, you know, >> That's why there's a lot of
of these induced pluripotent Jamie Thomson's recent discovery
Then you don't have that immune rejection problem.
And I think that is something that's really going to change
the field.
that direction right now. The limitation is that those
cells are genetically engineered
to sort of get them back with viruses that came in,
So the current generation, I to stem cells.
comfortable using those for don't ththerapies.y would
Because where those viruses go
potentially lead to tumor or in, they can alter genes and
So this is a first step in the cancer formation.
ways to induce them. long-term, if we can find better
be very exciting. I think you'reYes?ht, that would
You mentioned that the
you're creating can be used for currendrug reactions.s that
Have any experiments been done
that out? w>> Well, I showed you oneed
example there where the action
particular drug that's known to potentibe an offender.ith the
So we have, in our lab, in the
few drugs and shown that in a orsmall subset, it has somed a
predictive value. Of course, the literature out
there, there are thousands and
how good this test is, we really tens of thousands of drugs, so
drugs. need to go through a lot of
my knowledge. And thI think in the back.yet to
With your last announcement,
national news and reading the national papers, it was always
experts from Chicago or someplace else that were talking
about what Jamie did. The University of Wisconsin was
hardly mentioned. Didn't you guys feel slighted?
Well, you know, the question
( laughter ) is...
with the announcement of the If you didn't hear it,
the experts were not from inWisconsin, talking about it.,
And my own impression of that is, is that typically when
discoveries are made, the media,
to get independent, outside eexperts that aren't tied in toe
the research. Of course if you talk to
researchers at Wisconsin, they're going to tell you it's
the greatest thing since sliced bread.
So they want to find a somewhat independent, credible scientist
somewhere else to discuss it. So I think that's driving a lot
of those expert comments from around the world.
And frankly, I'd rather be the
having the discoveries made. institution developing it and
our work here. Let everybody else talk about
Yes? That's fine by me.
Is anybody doing any work on I think up front.
cells in the heart to do the stimulating the existing stem
The question is, is anybody studying how to stimulate the
endogenous stem cells in the
People are looking at that, and are trying to add cytokines,
or signaling molecules that are soluble, to turn on those.
First we have to understand what
still learning that. turns on those cells, and we're
to be able to see that they're Then we have to be good enough
So people are looking at that. turned on and what they do.
understanding what's called a And parniche.hat is
So where those cells live in the
environment, and how to foster heart, and that specialized
So people are looking at that. that.
though. IYes, another question in the
front?
say that NIH was spending >> $26 million on stem cellou
research. If one does the calculation,
that's about what it costs for
I wonder if you could comment on one hour in the war in Iraq.
So the question is the NIH is spending $28 million on stem
cell research in the U.S. And that's roughly equivalent
to the cost of one hour of
And my comment on that is it funding for the Iraq War.
But to comment more than that, wouldn't be my choice.
unfortunately, to change it. I'm not in a position,
I believe you said earlier I think over here, yes?
I was just curious, is there any that stem cells are circulating.
when a tissue is injured that ngenerates a signal that sayse
it's in need of stem cells? >> That's a great question.
The question is, stem cells are going around in the circulation.
And is there a signal when
tissue, come help me out. therAnd I think there is.cular
And those signals overlap what
signals for inflammation. So when you have a heart attack,
your heart gets filled up with
that in part chew up the damaged blood cells, white blood cells
But it's probably also a signal to bring in some cells to try
and help repair it. And it's the same with damage in
other organs. There are signaling molecules
that cause these cells
We don't really understand them ttoo well.e.
And the real problem is that
in relatively low numbers. most of these cells are present
human heart has in the range of Sfour billion muscle cells.
So if you start doing the math, it's hard to get four billion
stem cells into the heart.
very small number of cells with So ya massive task at hand.ith a
So there are ways to get those
are being dissected out. cells out, and those pathways
You talked about heart A question over here?
I wondered if you would just tissue.
successes or failures on comment on clinical trials and
So the question is, I've had regenerating tissues.
talk. And what's happening in other
tissues.
tissues as there are, there are beginning explorations of
clinical trials.
neuro diseases, primarily Parkinson's disease where fetal
tissue is put in patients with
That was really done in the late Parkinson's disease.
But there are new trials with new sources of the dopaminergic.
neurons being considered. There's a trial here on campus
using a human cell line that can
And in patients that have had bad burns that can't have grafts
because they've been burned over
they've normally gotten 80cadaveric skin grafts.,
So Lynn Allen-Hoffman is leading
stem cell that she's growing in tissue culture that can form,
they're called NIKS, Nearly Immortalized Kerotinocytes.
And so they can form skin cells,
grafting. and pThere are a variety of skin
orthopedic applications where stem cells have been used, and
tissue engineering for repairing
There's a variety of other bone.
board. things that are on the drawing
the most exciting is for One of the ones that I think is
And diabetes, sort of the proof of principle experiments have
been done, if we can get the
cell therapy. That is, as you may or may not
know, juvenile onset diabetes is
cells in the pancreas. due to a loss of functional beta
secrete insulin. So they are lost, so you can't
cadaveric donors, brain-dead And so taking islets out of
beta cells and then injecting them into the liver, actually
through the portal vein, in patients with diabetes, and
immunosuppressing them, so they don't reject those cells, has
successfully treated Type 1 diabetes and the patients have
glucose control.
donor, isolate those cells, put You them into a patient andorgan
potentially cure diabetes, with the caveat that you have to be
on immunosuppressives, which is a problem.
But to me, that tells me that if
stem cells, and can get stem we continue to work with these
cells, that's going to be a disease that may be amenable to
cell based therapy in the not-too-distant future.
So there's, you know, a vast
I can't touch on them all, nor array.
all. am I qualified to touch on them
What is the basic difference Yes?
cells? between stem cells and cancer
The question is what's the >> That's a good question.
and a cancer cell. difference between a stem cell
great. I've told you stem cells are
culture. They keep growing forever in
But I could've said, cancer Wcells, they're bad.?
They keep growing forever.
overlap. And so they clearly have some
populations are fairly quiescent Most of our stem cell
That's one of the things that defines them.
They don't really divide much until they're stimulated.
They respond to the local environment in their ability to
differentiate and form various
But cancer cells have sort of lost that check on their growth
control.
They don't turn off in response to the signals around them.
There is an emerging concept of a cancer stem cell.
So a cancer stem cell is that cell that's sort of slowly
dividing that can give rise to
rapidly grow and cause the the new cancer cells that
And some investigators believe problem.
cancers therapies is related to the inability to get rid of they
cancer stem cell. It's sort of sitting there,
hiding their in the background, and it's the fast dividing
cancer cells we can get rid of. If you don't get rid of the
cancer stem cell, the cancer
So some of the biology clearly comes back.
Some of the gene regulation programs, some of the cell cycle
programs, the ability of the
But their behavior is distinctly cells to divide overlap.
Metastasized cancer cells sound like pluripotent stem
cells in a way. >> It does.
So metastasizing cancer cells,
cells going anywhere in the are they likbody?ripotent stem
Probably not. These are cells that have some
lineage commitment. In other words, if you've got
lung cancer, these cells have some similarity to lung tissue,
either an epithelial form or a
form. sAnd when they metastasize,t
they still show that phenotype. So they don't go to the liver
and become liver. If they were pluripotent cells
and went to the liver and became
heart, that'd be great. more But they don't.ed the
They sort of are committed to that lineage.
But they're abnormal in their growth control.
They don't turn off when normal cells stop dividing.
They do clearly overlap.
I know the brain is not your Yes?
controls most of us. part of the body, but the brain
And how does that impact ( laughter )
that they're working on in the rest of the stem cells
working on. >> The question is how does the
brain feedback on other stem
an overriding controller. cI think there's no doubt thate
the signaling, that the nervous system impacts cardiac function
in many ways. We know that from when you get
excited, your heart rate goes up.
And there are a variety of
stimulate the heart that may adrenaline like molecules that
So there may be some impact stem cells.
I don't think in general, though, we think the brain has
specific, strict oversight of all the stem cell populations in
the body. At least our current
understanding.
And as I always tell my neurologic colleagues, the brain
doesn't matter if your heart
( laughter ) stops.
so I worked on the heart. I can't underYes?d the brain,
Do you think the field of epigenetics is going to have an
impact on this work?
field of epigenetics have impact >> So the question is will the
And so obviously we have an educated audience here.
But for the few that don't know the difference between genetics
and epigenetics, standard genes,
about all the time, we DNA, what we've sort of talk
in our cells have a DNA encoding understand that our chromosomes
off, and create the proteins specific genes that turn on and
live. But epigenetics is sort of a
different control mechanism.
structure of those genes, so Sort of modifying the overall
And whether they're methylated, or other impacts on the gene, so
they're available to turn on and
And it's the epigenetics that really allows us all to commit
to a particular lineage and not be able to go in other
directions, to a large extent.
induced pluripotent stem cells, Sepigenetics is a giant fielde
which will be explored, and quite important.
We really don't understand
the genome to be active in what's allowing certain parts of
We're learning, and there's a lot of advances, but we're just
starting to scratch the surface,
In the back? so that will be important.
So there was an investigator ( inaudible )
Sorry, the question is what about stem cell research and
multiple sclerosis. And Ian Duncan here on campus is
in the Vet school, and actually studies the abilities of stem
cells as a potential treatment
Multiple sclerosis is an for multiple sclerosis.
what's called a demyelinating interesting disease.in that it's
So the axons, the particular
out distally, to go to the parts of the nerves that send
wrapped in a special sort of various parts of the body, are
And with multiple sclerosis, insulator called myelin.
dysfunctional. they lose that myelin and become
cells in there that would So protect that myelin andget
re-myelinate them, you may
That's ongoing work. be able to treat MS.
to clinical trials yet, but Ipeople are exploring in animal
models the ability to treat MS. >> Thank you very much.
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)