Immunotherapy
Myth or Reality?
Doug Joshua
Institute of Haematology, Royal Prince Alfred Hospital,
Sydney, Australia.
May , 2011
X111TH MYELOMA WORKSHOP
PARIS
Ross Bown, Joy Ho, John Gibson, Derek Hart
Immunotherapy for Myeloma
Myth or Reality?
· The potential
Plateau phase disease and SMM infers host tumour interaction
GVM well documented, even in drug refractory patients
Expanded Clonal T cell populations are present and protective
Cytotoxic T cell can be developed against autologous myeloma cells in vitro
· The claims
· The facts
· The conundrum
· The solution
1
Immunotherapy The claims
Immunotherapy may be used in multiple myeloma treatment to help:
· Make myeloma cells more recognizable, and therefore, more
susceptible to destruction by your immune system
· Boost the killing power of your immune system cells, including T
cells, NKcells and macrophages
· Enhance your body's ability to repair or replace normal cells
damaged or destroyed by other forms of multiple myeloma
treatment, such as chemotherapy or radiation
· Prevent myeloma cells from spreading to other parts of your body
The potential
Microbial model
Virus
Bacteria
Cancer Cells
2
Virus
Induced Tregs or
CD80 or HLAG acquired Tregs
regulate tumour escape
Trogocytosis
TROGOCYTOSIS
Bacteria
Myeloma Cell
My
as
eloma APC
or
Cancer Cells
Immunotherapy Myth or Reality?
The issues
· Active immunotherapy requires
tumour rejection antigen,
adjuvant
stimulation of an correct immune response
the development of long term immunological
memory
· Minimise risk of autoimmunity
· Prevent tumour immune evasion and
tolerance
3
Possible antigens
· Tumour specific
· Idiotype ?
· Can we generate heteroclitic peptides with high affinity for
the T cell receptor?
· Is there a generic or differentiation antigen?
DKK1, MAGE 3, NYESO1, SP17
Mutational antigens derived from myeloma genome
sequencing eg RAS
Myeloma associated antigens
· Idiotype , while being unique to malignant cell is rarely
immunogenic
· No concept of what constitutes a rejection antigen in
humans other than allo antigens , eg GVM
· RNA and DNA immunization antigens techniques offer
possibilities but choice of antigen remains problematic
and initial clinical trials disappointing
· In vitro cytotoxicity does not necessarily translate into in
vivo rejection.
· Barriers at the level of the microenvironment
· Does dendriticmyeloma cell fusion overcome these
issues?
4
DC issues for active immunisation trials in
myeloma
· What is the optimum DC population?
· Do in vitro loaded DCs overcome the in vivo DC defect?
· Do responses to DC loaded TAAs eliminate myeloma
stem cells , as well as mature plasma cells ?
· Is the immune system already primed by the presence
of the malignant plasma cell ?
How do we break tolerance?
Immunotherapy Myth or Reality?
The Facts
Lots of
· Active immunotherapy
studies No
Immunisation
really
CLINICAL
Peptide or DNA/RNA
dramatically
Adjuvants
successful
Dendritic cells
results
5
Immunotherapy Myth or Reality?
· Passive immunotherapy
Antibodies
Immune modulating antibodies
Anti CS1, Anti CD38, anti CD40
NK cells
T cells
Stimulation of ADCC (CD137 or lenalidamide)
ADCC in Myeloma
Myeloma Cell
Y
Y
Y
Y
Coat myeloma
cells with specific
antibody
Antib
ody
Stimulate NK with
Antibody
CD137 ligation
dependent
Upregulate
cell
CD137
cytotoxicity
on NK
cells
6
Immunotherapy Myth or Reality?
The Conundrum
· The conundrum of myeloma immunology
· Why is the first malignant plasma cell not destroyed?
· Non immunodominant antigen
· A tumour antigen may not be a rejection antigen
· Impaired function of Dendritic cells
· Low affinity T cells made anergic by failure of second message
· Evasion of immune recognition
· Generation of Treg inhibition
Tolerance of the immune system
The Myeloma is Just too Smart
The cellular and molecular interactions involved with
immune suppression in myeloma are complex
T cells with acquired antigens
X
iTreg -T cells acquire antigens by
trogocytosis and regulate tumor
escape
Dysfunctional
DC
Tumor
Antigens
(
Th17
Plasma
TGF +
cell
IL10
Treg
nTreg
TGF
Cytokine storm
IL2
7
How does the Malignant Plasma Cell Hide?
· Expresses immunosuppressive molecules , eg
HLAG which inhibit NK function
· Secretes immunosuppressive cytokines eg
TGF to enhance Tregs and impair DC
function
· Develops marked heterogeneity with
chromosomal evolution.
HLAG in Patients with Myeloma
HLAG expression on BM plasma cells is varied
HLAG is present at low
100
Patient No 1 Patient No 2
n
levels on blood T cells
io
lls
80
ess
cea 60
expr
asm
n=51
0.4
PE
0.7%
pl
40
-G
%
AL BM
CD38
H
20
%
on
PerCP
0
HLAG FITC
0.1
CD3
Myeloma patients
%
HLAG FITC
HLAG+ BM plasma cells = poor prognosis
HLAG Neg
s
20% of MM patients have
llec
increased HLAG on T cells
1.5
T+3D
F=3.7
HLAG Pos
C
P<0.01
n
1.0
o
2
n
=12.4;
io
p<0.001
ress
0.5
p
ex
-GA 0.0
L
H
Aged matched controls
Myeloma patients
%
8
CD3 cells with acquired
antigens(trogocytosis) inhibit
proliferation of CTL
M3
Dendritic Cells
· Vaccination with antigen pulsed autologous DC
requires efficient cross presentation of TAA to
T cells to elicit antitumour responses in the
tumour microenvironment.
· This requires DC to not only migrate efficiently to
sites of antigen presentation such as the BM in
MM but also to induce functional CTL responses
capable of lysing tumour cell targets.
9
Dendritic Cells
· DC are dysfunctional in myeloma
· Can we reverse with exvivo manipulation of DC ?
· Which DC will actually be the antigen present cells ?
· Do infused DC go to the bone marrow?
· Monocyte derived DC (MoDC) are functionally quite
different to blood DC and display an unstable phenotype
reverting to a monocytic lineage once DC differentiating
cytokines such as GMCSF are withdrawn.
2. DC function
X
DC function
is blocked by
is
Decreased
blocked by
Decreased
Antigen presentation
function
function
tumourderived fact
tumour ors
derived
factors
DC function blocked by tumourderived
DC function blocked by tumourderived
factors eg. TGF
IL12 restores
factors eg. TGF
DC function
Myeloma
Myeloma
cell
cell
TGF
DC
DC
Brown,Joshua et al. Blood 2001; 98:2992
M3
10
Dendritic Cell Subtypes
CD141+ equivalent of mouse CD8+ DC
can cross present necrotic cell antigens
Isolation of CD141+ DC and CD1c+ DC from apheresis products.
Jongbloed S et al. JEM 2010;207:1247-1260
© 2010 Jongbloed et al.
11
The Cytotoxic T cells in MM
· Expanded clones of
cytotoxic T cell are
present (TCRV analysis)
· Expanded clones
are associated
with prolonged survival and
interact with immunomodulators
100
% 80
·
ee
TCR sequencing of the
T cell clones + thal
Frn 60
o
clonal T cells are
40
essi
heterogeneous
rogr 20
P
No clones
0
0
10
20
30
40
50
60
70
Months
Functional proof of anergy
4 day CFSE proliferation assays
TCRV20
TCR V20+
Proliferating T cells 62% 0%
Nonclonal
Clonal
Can the anergy be reversed ?
Cytokines,CD137, +/ IL12 producing SlanDC
Li, Brown, Joshua et al BLOOD 2010 115:3580
12
Some Possible Solutions
1. Change the paradigm
2. Realise that the tumor has control
3. Neutralise the inhibitory effects of the tumor
4. To vaccinate against myeloma
Reduce tumor load
Use high potency DCs .... CD 141 +subset
Use more than one tumor peptide
4. Break anergy and enhance cytotoxicity of possible primed
CD8 cytotoxic cells ..... Slan DC `s ..CD137
5. Combination immunotherapy with active and passive
therapies
Immmunotherapy , now a myth, but soon reality
Purify high
Potency DC
Use multiple peptides
from tumor antigens
Virus
Expand CTL
Initiate NK
mediated ADCC
Neutralise
tumor
derived
Inhibitors
Treg
nTreg
Bacteria Treg
iTreg
Reduce nTregs
IL2
Myeloma Cells
Limit iTregs
IL2
Eg. HLAG+ T cells
13
Dendritic Cell Subtypes
SLAN DC Subset of CD16+ DC
High IL12 production, can we
use themto break T cell
anergy?
Restore TCR and CD8 co
localisation
MULTIPLE MYELOMA
Multiple Myeloma is Heterogeneous
multiple clones multiple properties
* *
*
instability
*
**
ic
control
enomG
*
*
&
*
Immune
*
*
nancy
Malig
*
*
Plasma cell viability *Potentialstemcell
14
rTGF increases
inhibitory function of Treg
rTGF
rIL-12
100
eg
50
Trni tye
Tre
Tr g
ivi
0
eg
act
hangC
-50
%
TGF
-100
Myeloma
cell
TGF
DC
M3
Improving Immunotherapy Making passive therapy into active therapy
ADCC by NK cells following antibody therapy The Lymphoma Model
Enhancement of Rituximab efficacy in lymphoma due to CD137 ligation following anti
CD20 priming of tumor cells
Blood 2011; 117: 24232432
Consider ADCC in myeloma Antibody therapy plus sequential anti CD137 ligation
15
Tumour Marker (paraprotein)
90
Escape phase
70
L
g/
blood in 50
ein
Host disease control
ot
r pru
Smouldering
om 30
phase
Tu
10
1996 2000 2004
2008
T cell clones are anergic
Li, Brown, Joshua et al BLOOD 2010 115:3580
16