TLR ligand functionalized nanocarriers to enhance immunogenicity of vaccines
USP CHOP Annie De Groot Presentation June 2013
1. Andres
H.
Gu,érrez,
Leonard
Moise,
Frances
Terry,
Kristen
Dasilva,
Chris
Bailey-‐Kellogg,
William
Mar,n,
Anne
S.
De
Groot
Immunoinforma2c
analysis
of
Chinese
Hamster
Ovary
(CHO)
protein
contaminants
in
therapeu2c
protein
formula2ons
Measurement
of
Residual
Host
Cell
Protein
and
DNA
in
Biotechnology
Products
June
3,
2013
2. How
did
we
get
to
HCP/CHO/CHOPPI?
2002
Invita,on
to
“Predic,ng
Biologic
Protein
Immunogenicity”
Conference
at
FDA
2011
CHO
Genome
Published
2006-‐2007
Immunogenicity
scale
Tregitopes,
Collabora,on
With
Gene
Koren
and
others
CHO
genome
immunogenicity
analysis
Plenary
at
ECI
CCE
conference
HCP
/
CHO
Cells
Host
Cell
Proteins
Parallels
with
Graves’
model
2004
Benchmarking
Vaccine
tools
for
Biologics:
Clustered
T
cell
epitopes
EpiBars
CHOPPI
On
line
.
.
.
3. Why are we interested in the Impact of species-
specific sequences on immunogenicity?
Autoimmune
Graves
Disease
Graves Disease Example
4. “Autoimmune
Graves
Disease”
begins
with
a
response
to
a
single
epitope
that
is
mismatched
and
presented
in
the
context
of
murine
MHC
hTSHR variant 1_NM_000369 and murine TSH-R mTSHR variant 1_NM_011648 alignment
mTSHR_variant_1_NM_011648 PPSTQTLKLIETHLKTIPSLAFSSLPNISRIYLSIDATLQRLEPHSFYNL
hTSHR_variant_1_NM_000369 PPSTQTLKLIETHLRTIPSHAFSNLPNISRIYVSIDVTLQQLESHSFYNL
peptide 5-6 (78-94) (variant)
Graves Disease Example
5. • Epitope fully conserved in human and murine FVIII:
• Tolerated in FVIII-expressing HLA DR mice (have autologous FVIII)
• Immunogenic in FVIII KO mice (do not have any FVIII)
• Epitopes containing human/murine FVIII sequence mismatches:
• immunogenic in FVIII-expressing HLA DR mice (foreign)
• immunogenic in FVIII KO mice (still foreign)
FVIII KO
Not KO
FVIII Example (murine)
6. Murine'response'to'TSH/R Mouse'Sequence'same'as'Hu Mouse'Sequence'Different
T'cell'Epitope'Present Tolerance Immunogenicity
T'Cell'Epitope'Absent No'Response'''' Absent'epitope,'no'response
Human'response'to'HCP Human'Sequence'Same'as'CHO Human'Sequence'Different
T'cell'Epitope'Present Tolerance Immunogenicity
T'cell'Epitope'Absent No'Response'''' Absent'epitope,'no'response
Mice
immunized
with
human
TSH-‐R
Humans
exposed
to
CHO
or
other
HCP
Important Parallels – HCP effects
8. Pathogen
Immune
Response?
Self/
Microbiome
8
Ac,ve
area
of
research
-‐
EpiVax/URI
9. HCP
Contamina,on
cancels
trial
Immune
response
to
HCP
(CHO)
led
to
recent
cancella,on
of
phase
III
clinical
trials:
“Higher
than
expected
rate
of
An,-‐
CHO
an,body
development”
(what
is
expected????).
IB1001
–
hemophilia
(Inspira3on
Biopharmaceu3cals)
10. • Danger
signals
of
all
sorts
• Aggregates
–
how
do
they
work?
– (probably
don’t
work
if
no
T
cell
epitopes)
– Immune
complexes
–
Complement
• T
cell
epitope
content
• (absence
of)
Treg
epitope
content
• Pre-‐exis3ng
T
cell
response
(Tolerance
or
heterologous
immunity)
What
drives
immunogenicity?
11. Factors (↑roof Immunogenicity) Immune effect
Glycosylation (↑) Increase presentation? Increase foreign-
ness of protein, need T cell epitopes
PEGylation (↓) Slow antigen processing, “mask” T cell
epitopes and B cell epitopes
Host Cell-derived Protein (↑) CPG DNA (if bacterial); CHO T cell epitopes
Oxidized Form of the Product (↑) Increase foreign-ness, modify presentation
Excipients (↑) Increase Danger signal, T cell epitopes
Leachates (↑) Increase Danger signal, T cell epitopes
Characteristics of Patients (↑or↓) Missing Protein is foreign, T cell epitopes
Frequency, Duration and Route of
Administration (↑or↓)
Administration like a vaccine, DAMPs, T cell
epitopes
Aggregates (↑) Aggregation increases T cell epitope
presentation
In almost every case
Mechanism of Action – T cell Response
In
almost
every
case
–
T
cell
epitope
drives
Immune
response
13.
In
the
right
context
self
proteins
can
be
immunogenic.
Take
Epo†,
for
example.
T
cell
epitope
content
is
unequally
distributed
throughout
the
human
(and
CHO)
proteome.*
Immune
response
depends
on
protein
prevalence,
func,on
&
previous
exposure.**
†
Marc
H.V.
van
Regenmortel,
Ph.D.,
Ka,a
Boven,
M.D.,
Fred
Bader,
Ph.D.
Immunogenicity
of
Biopharmaceu,cals:
An
Example
from
Erythropoie,n:
Protein
structure,
contaminants,
formula,on,
container,
and
closure
all
can
affect
the
immunogenicity
of
the
product.
BioPharm
Interna,onal
2005.
hmp://www.biopharminterna,onal.com/biopharm/ar,cle/ar,cleDetail.jsp?id=174494&sk=&date=&pageID=5
*A.S.
De
Groot,
J.
Rayner,
W.
Mar,n.
Modeling
the
immunogenicity
of
therapeu,c
proteins
using
T
cell
epitope
mapping.
In:
Immunogenicity
of
Therapeu,c
Biological
Products.
Developments
in
Biologicals.
Fred
Brown,
Anthony
Mire
Suis,
editors.
Basel,
Karger,
2003.
Vol
112:71-‐80.
**Clute,
S.
C.,
L.
B.
Watkin,
M.
Cornberg,
Y.
N.
Naumov,
J.
L.
Sullivan,
K.
Luzuriaga,
R.
M.
Welsh,
and
L.
K.
Selin.
2005.
Cross-‐reac,ve
influenza
virus-‐specific
CD8+
T
cells
contribute
to
lymphoprolifera,on
in
Epstein-‐Barr
virus-‐associated
infec,ous
mononucleosis.
The
Journal
of
clinical
inves,ga,on
115:3602-‐3612.
CHO
are
mammalian
proteins
–
How
can
“self”
proteins
be
immunogenic?
14. T
Cell
Epitope
Content
-‐
Predicted
Poten,al
for
Immunogenicity
of
Selected
Proteins
-‐80
-‐60
-‐40
-‐20
0
20
40
60
80
100
Human
FSH
beta
Human
IgA
CD
Human
IgG
CD
Human
Albumin
Human
Amylase
De-‐immunized
INF-‐beta
Human
Transferrin
*
Human
Gonadotropin
Random
Expecta,on
Influenza
Hemagglu,nin
*
Human
GHRH
*
Human
Gonadotropin
w/signal
Tetanus
Toxin
Human
Erythropoie2n
Brazil
Nut
An,gen
*
Human
GHRH
w/signal
**
Human
INF-‐
beta
Less
Immunogenic
Proteins
(based
on
clinical
experience)
Have
Fewer
T
cell
Epitopes
De
Groot,
As,
Goldberg
M,
Moise
L,
Mar,n
W.
Evolu2onary
deimmuniza2on:
An
ancillary
mechanism
for
self-‐tolerance.
Cell
Immunol.
2007
Apr
17;
Pages
148-‐153.
hmp://dx.doi.org/10.1016/j.cellimm.2007.02.006
Are
self
proteins
immunogenic?
15. EpiVax
Immunogenicity
Hypothesis:
Immune
Response
=
Sum
of
Epitopes
T
cell
response
depends
on:
T
cell
epitope
content
+
HLA
of
subject
Protein
Immunogenicity
can
be
Ranked
epitope
Protein
Therapeu,c
1
+
1
+
1
=
Response
epitope
epitope
• De
Groot
A.S.
and
L.
Moise.
Predic,on
of
immunogenicity
for
therapeu,c
proteins:
State
of
the
art.
Current
Opinions
in
Drug
Development
and
Discovery.
May
2007.
10(3):332-‐40.
In
biologics,
immunogenicity
is
related
to
T
cell
epitope
content
16. EpiVax
-‐
Immunogenicity
Scale
Low
Neutral
High
Albumin
Tetanus
Toxin
Protein
X
or
mAb
Y
Proteins
ranked
by
T-‐
Epitope
content
per
Amino
Acid
•
De
Groot
A.S.,
Drug
Discovery
Today
-‐
2006;
•
De
Groot
A.S.,
Mire-‐Sluis,
A.
Ed..
Dev.
Biol.
Basel,
Karger,
2005.
vol
122.
pp
137-‐160.
An,gen
A
An,gen
B
Aggregate
immunogenicity
drives
Immune
response
17. EpiMatrix
predicted
excess/shorwall
in
aggregate
immunogenicity
rela,ve
to
a
random
pep,de
standard.
-‐
80
-‐
-‐
70
-‐
-‐
60
-‐
-‐
50
-‐
-‐
40
-‐
-‐
30
-‐
-‐
20
-‐
-‐
10
-‐
-‐
00
-‐
-‐
-‐
10
-‐
-‐
-‐
20
-‐
-‐
-‐
30
-‐
-‐
-‐
40
-‐
-‐
-‐
50
-‐
-‐
-‐
60
-‐
-‐
-‐
70
-‐
-‐
-‐
80
-‐
Thrombopoie2n
Human
EPO
Tetanus
Toxin
Influenza
-‐
HA
Albumin
IgG
FC
Region
EBV
-‐
BKRF3
Follitropin
-‐
Beta
A
protein
score
>
20
indicates
a
significant
immunogenic
poten,al.
Proteins
that
have
previously
been
demonstrated
to
be
immunogenic
have
higher
poten,al
immunogenicity
on
the
scale.
Those
that
have
rarely
been
demonstrated
to
be
immunogenicity
have
lower
T
cell
epitope
content.
Immunogenicity
scale
19. - 80 -
- 70 -
- 60 -
- 50 -
- 40 -
- 30 -
- 20 -
- 10 -
- 00 -
- -10 -
- -20 -
- -30 -
- -40 -
- -50 -
- -60 -
- -70 -
Human EPO
Immunogenic Antibodies*
Tetanus Toxin
Influenza-HA
Albumin
IgG FC Region
EBV-BKRF3
Fibrinogen-Alpha
Non-immunogenic Antibodies†
Follitropin-Beta
Hirudin(-‐90.41)
See
my
Blog
“Thinking
out
Loud”
for
a
discussion
of
Leech
proteins
and
Tick
Saliva
proteins-‐Tick
saliva
proteins
also
have
low
immunogenicity
poten,al.
Hirudin
–
Very
Low
Poten,al
Immunogenicity
-‐
Why?
Other Antigens – Extremely Low Scores
(Hirudin, Tick Saliva, Some Parasites)
20. • Handled on a case-by-case basis
• Consider Source
• Maximum dose (mg biologics/kg body weight)
• Route of administration
• Frequency of dosing
• Pre-clinical and clinical data
• Detection process in evolution
The FDA Prefers Leech-like Proteins
And HCPs - Regulatory Perspective
21. HCP Analytical Technologies
• Detection
– Protein staining
– Immunoblotting
• Identification
– 2D-PAGE/MS
– 2D-LC/MS
• Quantitation
– ELISA using anti-HCP antibodies
– May need to develop internal processes
– Some kits are available
• Risk assessment
– Cytokine release assays
New
Approach
–
Immunogenicity
Screening
in
silico
Analytical Tests for HCP
22. • MHC
binding
is
a
prerequisite
for
immunogenicity
• Epitopes
are
linear
and
directly
derived
from
an,gen
sequence
• Binding
is
determined
by
amino
acid
side
chains
• Matrix-‐based
predictor
MHC
II
Mature
APC
Immunogenicity
predic,on
23. EpiMatrix
• EpiVax
uses
EpiMatrix
to
predict
epitopes
– matrix
based
predic,on
algorithm
• Can
predict
either
class
I
or
class
II
MHC
binding
– MHC
binding
is
a
prerequisite
for
immunogenicity
MHC
II
Pocket
Pep,de
Epitope
Mature
APC
MHC
II
T
cell
epitopes
are
linear
and
directly
derived
from
an,gen
sequence
Binding
is
determined
by
amino
acid
side
chains
(R
groups)
and
‘encoded’
in
single
lemer
code
23
6/3/13 Confidential
24. Easy
easy
to
deliver
as
pep,des
Clusters
of
MHC
binding
drive
T
cells
DRB1*0101
DRB1*0301
DRB1*0401
DRB1*0701
DRB1*0801
DRB1*1101
DRB1*1301
DRB1*1501
• T
cell
epitopes
are
not
randomly
distributed
but
instead
tend
to
cluster
in
specific
regions.
– These
clusters
can
be
very
powerful,
enabling
significant
immune
responses
to
low
scoring
proteins.
• Clus,Mer
recognizes
T-‐cell
epitope
clusters
as
polypep,des
predicted
to
bind
to
an
unusually
large
number
of
HLA
alleles.
6/3/13 Confidential
25. What
Makes
Proteins
Really
immunogenic?
Sequences
that
Contain
EpiBars
Confiden,al
Roberts
CGP,
Meister
GE,
Jesdale
BM,
Lieberman
J,
Berzofsky
JA,
A.S.
De
Groot,
Predic,on
of
HIV
pep,de
epitopes
by
a
novel
algorithm,
AIDS
Research
and
Human
Retroviruses,
1996,
Vol.
12,
No.
7,
pp.
593-‐610.
Clus,Mer
-‐
Locates
highly
immunogenic
regions
EpiBar
:
A
common
feature
of
highly
immunogenic
clusters
EpiBar
26. EpiVax
Immunogenicity
Scale
Confiden,al
- 80 -
- 70 -
- 60 -
- 50 -
- 40 -
- 30 -
- 20 -
- 10 -
- 00 -
- -10 -
- -20 -
- -30 -
- -40 -
- -50 -
- -60 -
- -70 -
- -80 -
Thrombopoietin
Human EPO
Immunogenic Antibodies*
Tetanus Toxin
Influenza-HA
Albumin
IgG FC Region
EBV-BKRF3
Fibrinogen-Alpha
Non-immunogenic Antibodies†
Follitropin-Beta
PROTEIN_001 (35.13)
Protein Immunogenicity Scale
Proteins Scoring above +20 are
considered to be potentially
immunogenic.
On the left of the scale we
include some well-known
proteins for comparison
- 80 -
- 70 -
- 60 -
- 50 -
- 40 -
- 30 -
- 20 -
- 10 -
- 00 -
- -10 -
- -20 -
- -30 -
- -40 -
- -50 -
- -60 -
- -70 -
- -80 -
Thrombopoietin
Human EPO
Immunogenic Antibodies*
Tetanus Toxin
Influenza-HA
Albumin
IgG FC Region
EBV-BKRF3
Non-immunogenic Antibodies†
Follitropin-Beta
27. EpiMatrix
mAb
Immunogenicity
Scale
- 80 -
- 70 -
- 60 -
- 50 -
- 40 -
- 30 -
- 20 -
- 10 -
- 00 -
- -10 -
- -20 -
- -30 -
- -40 -
- -50 -
- -60 -
- -70 -
- -80 -
IgG FC Region
Nuvion (0%)
Avastin (0%)
AB01 (EPX Adjusted Score: -46.98)
AB02 (EPX Adjusted Score: -44.48)
AB03 (EPX Adjusted Score: -44.81)
AB04 (EPX Adjusted Score: -45.81)
AB05 (EPX Adjusted Score: -45.88)
AB06 (EPX Adjusted Score: -47.85)
AB07 (EPX Adjusted Score: -46.99)
AB08 (EPX Adjusted Score: -46.30)
AB09 (EPX Adjusted Score: -47.40)
AB10 (EPX Adjusted Score: -45.88)
AB11 (EPX Adjusted Score: -47.40)
Synagis (1%)
Simulect (1.4%)
Humira (12%)
Bivatuzumab (6.7%)
Remicade (26%)
Rituxan (27%)
Campath (45%)
Humicade (7%)
Reopro (5.8%)
Tysabri (7%)
LeukArrest (0%)
Herceptin (0.1%)
Compare
with:
27
6/3/13 Confidential
Due
to
the
presence
of
Tregitopes,
an,bodies
tend
to
fall
lower
on
the
immunogenicity
scale.
We
have
developed
a
refined
method
using
regression
analysis
to
predict
the
immunogenicity
of
an,body
sequences
based
on
observed
clinical
responses
(next
slide).
We
have
found
that
a
balance
in
favor
of
Tregitope
(regulatory)
content
over
neo-‐epitope
(effector)
content
is
correlated
with
reduced
clinical
immunogenicity.
NeoEpitopeContent
Tregitope Content
High
Low
Low
Avastin (0%)
Herceptin (0%)
Mylotarg (3%)
Simulect (1%)
Synagis (1%)
High
Campath (45%)
Remicade (26%)
Rituxan (27%)
28. CHO
genome
Immune
Response?
Self/
Microbiome
28
Logical Next Step
measure CHO/Self Conservation
31. • Protein databases (UniProtKB/Swiss-Prot, Locate)
• BLAST
• SignalP
• EpiMatrix
• BlastiMer - JanusMatrix
Tools used for this analysis
32. • Identify secreted CHO proteins
• Collect published HCP from CHO
• Evaluate potential immunogenicity
• Evaluate sequence homology
• Identify clustered regions – compare to CHO;
• Are human/CHO different at the cluster? Count
as possible immunogenicity trigger.
Approach
37. Putatively
Secreted
(signal
peptide)
Mouse
secreted
165
proteins
Transcriptome
32,801
contigs
Validated
HCP
contaminants
25
proteins
CHO
genome
24,383
predicted
genes
Human
proteome
20,238
proteins
Approach
to
conserva,on
with
Human
38. • Identify secreted CHO proteins
• Evaluate potential immunogenicity
• Evaluate sequence homology
• Identify clustered regions – compare to CHO;
• Are human/CHO different at the cluster? Count
as possible immunogenicity trigger.
Approach
39. T
cell
Receptor
Face
(epitope)
MHC-‐binding
Face
(agretope)
T
cell
epitopes
are
two-‐faced
40. Identifies cross-reactive peptides:
• Identical T cell-facing residues
• Same HLA allele but . .
• OK if different MHC-facing residues
The
God
of
Two
Faces:
JanusMatrix
41. TCR
face
vs.
MHC
binding
face
MHC/HLA
TCR
The most conservative approach:
• Identical T cell-facing residues
• Same HLA allele and minimally different
MHC-facing residues
44. Cross-‐reactivity
visualization
Predicted
9-‐mer
epitope
from
a
source
protein
Human
protein
where
cross-‐reactive
epitopes
are
present
9-‐mer
from
human
prevalent
proteome,
100%
TCR
face
identical
to
source
epitope
Source protein
HCV_G1_NS2_794
50. • Identify secreted CHO proteins
• Evaluate potential immunogenicity
• Evaluate sequence homology
• Identify clustered regions – compare to CHO;
• Are human/CHO different at the cluster? Count
as possible immunogenicity trigger.
New Approach for CHO
51. Immune
Response
=
Sum
of
Epitopes
Sum
includes
+
(T
effectors)
and
–
(Tregs)
scores
Protein
Therapeu,c
Host
Cell
Protein
Contaminant
HCP
Epitope
New Approach
52. For
an
individual,
T
cell
response
depends
on:
T
cell
epitope
content
x
HLA
–
Treg
Epitope
content
x
HLA
Vaccine or Foreign Protein = (TeffPT1+
TeffPT2
.
.
.
)
=
Response
CHO = Σ (
TeffPT
+
TeffPT
+
TeffHCP
–
TregPT)
=
Treg
Adjusted
Response
Immune
response
depends
on
Foreign-‐ness
Potential
Tregs
Adjuvant
(Danger
signal)
Proposed adjustment to score
53. Available
now:
CHOPPI
CHO
Protein
Predicted
Immunogenicity
CHOPPI
hmp://bit.ly/11fZqfJ
55. • While CHO are the most
commonly used cell lines for
mammalian cell protein expression,
Company-specific cell lines may
vary. Furthermore, we can’t
anticipate
• Genetic engineering
• Batch-to-batch variation
• Expression (based on above)
• Which protein will ‘hitchhike’
CHO Cell lines may differ
57. Thank
you!
And
.
.
.
CHOPPI:
hmp://bit.ly/11fZqfJ
or
contact
me.
Translational Immunology Research and Accelerated [Vaccine]
Development Institute for Immunology and Informatics University of
Rhode Island
Dartmouth College
EpiVax, Inc. SL cytokine
58. Institute for Immunology and Informatics (iCubed)
D.
Spero
icubed
overview
2011
www.immunome.org
URI
Alumni
Board
2012
59. New
Concept:
Tregitopes
induce
tolerance
to
protein
Therapeu,cs
(Friday
April
20th
Session)
Epitope may induce different types of Response
60. CHO Adjustment for Immunogenicity ?
+
+
Conserved epitope Neo-Epitope
Neo-Epitope
61. Immune
Response
=
Sum
of
Epitopes
Sum
includes
+
(T
effectors)
and
–
(Tregs)
scores
ISPRI approach to analyzing mAbs . . .
T
cell
response
depends
on:
T
cell
epitope
content
x
HLA
–
Treg
Epitope
content
x
HLA
Protein
Immunogenicity
can
be
Ranked
Treg
epitope
Protein
Therapeu,c
1
+
1
-‐
Treg
=
Response
epitope
epitope
62. T
reg
S,mulus
IL
10,
TNF
alpha
Additional Treg Epitope
Modify Effector T cell response:
Reduce T effector Stimulus
Current Hypothesis: More Tregitopes
Lower Immunogenicity
De Groot A.S. and D. Scott. Immunogenicity of Protein Therapeutics.
Trends in Immunology. Invited Review. Trends Immunol. 2007 Nov;28(11):482-90.
631/29/11
63
Confiden,al
and
Copyrighted
EpiVax
65. Correlation of EpiMatrix Scores
and Immunogenicity in Human studies
40%
37%
21.97
FPX
1
0%
9.3%
-‐111.25
FPX
5
NA
0.5%
12%
Neutralizing
An,bodies
5.6%
7.8%
53%
Binding
An,bodies
-‐1.76
1.62
34.37
EpiMatrix
score
FPX
4
FPX
3
FPX
2
Protein
Na:
not
analyzed
Nega,ve
score
indicates
presence
of
Treg
epitope
66. - 80 -
- 70 -
- 60 -
- 50 -
- 40 -
- 30 -
- 20 -
- 10 -
- 00 -
- -10 -
- -20 -
- -30 -
- -40 -
- -50 -
- -60 -
- -70 -
- -80 -
Thrombopoietin
Human EPO
Immunogenic Antibodies*
Tetanus Toxin
Influenza-HA
Albumin
IgG FC Region
EBV-BKRF3
Fibrinogen-Alpha
Non-immunogenic Antibodies†
Follitropin-Beta
Ab K (-38.23)
Ab E (-16.03)
Ab N (-53.88)
Ab P (-70.14)
Ab B (-00.32)
Ab A (13.82)
Ab D (-08.87)
Ab F (-22.13)
Ab I (-25.77)
Ab O (-54.26)
Ab L (-48.49)
Ab C (-02.03)
Ab M (-52.25)
Ab H (-24.99)
Ab J (-28.94)
Ab G (-24.33)
*Tregitope
adjusted
Application – Germline Abs*