Good GVHD vs bad GVHD

What is the difference 
between beneficial graft versus host disease

and harmful graft versus host disease?

 So this is a really contentious topic.

So graft versus
host disease is where the graft,

which is the cells
you get from the donor, mount

an attack on the host,
which is the patient with myeloma.

So that it's graft versus host disease.

So the assumption is that
if your donors, immune cells can recognize

the recipient or the host
as a different person and attack them,

they can also attack the myeloma, which is
part of the recipient or the host.

So graft versus host correlates with what
we call graft versus myeloma effect.

So it is best to have no graft versus host disease

and have a graft versus myeloma effect.

Now, that does happen,
there are people who get a transplant

and they don't have any detectable
graft versus host disease,

and they basically have cleared
their myeloma successfully.

That is the luckiest option.

In some cases, you get what we call acute
graft versus host disease,

which is the type of graft resources
that happens right after transplant.

And that is usually associated
with some rash,

diarrhea, nausea, vomiting, liver
abdominal disease, etc.

And that comes and goes
and the patient still feels good.

And the anti
myeloma effect continues,

But very severe acute
graft versus host disease,

which is not controlled by
medication, can be fatal.

And that would not be a good thing
to have in any under any circumstances. So

we would

actually not we would wish for a minor
amount of graft versus host disease

that also eliminates the myeloma
as the good graft versus host disease.

Whereas if it's a long lasting
graft versus host disease,

more like chronic liver disease
and the data in myeloma,

allo transplant, is that chronic left
versus host disease at a limited level

does have some protection
against myeloma relapsing.

But as the acute bad graft versus
host disease

generally does not correlate
with a long sustained immune effect.

So this is, again, a controversial topic

in that you could have no graft
versus host disease

and an immune effect, a lot of graft
versus host disease and an immune effect.

But then you'd really wish
you didn't have the transplant at all

because the graft versus
host disease is just as bad.

So the golden balance

is to keep the patient with just enough

graft versus host disease
or just enough graft versus myeloma effect

and not do immune suppressed
so that the myeloma just stays away.

Is that luck of the draw
or are there therapies you can give?

So it's a lot of it would say
it's a little bit luck of the draw.

It is a little bit dependent
on the immune sensitivity of the myeloma

to the immune effect from the donor cells,
but we can actually ramp up

or down the immune effect
by adding more immune cells.

We call the donor lymphocyte infusions.

I have, for example, patients
who got donor lymphocytes

for their relapse 15 years ago,
got some new

fresh immune cells from the donor
and put them in.

And the patient has never looked
back in terms of getting myeloma again.

So for that person,
it would be luck of the draw

because we actually don't even know much
about myeloma in those days.

Now the

other scenario is that you can dial down

the immune suppression and wish for 
a little bit more graft versus host disease.

And sometimes there is a little
bit of an art to doing that.