U.S. patent application number 15/978390 was filed with the patent office on 2018-10-04 for bispecific constructs and their use in the treatment of various diseases.
The applicant listed for this patent is Numab Therapeutics AG. Invention is credited to Tea Gunde, Sebastian Meyer, David Urech.
Application Number | 20180282419 15/978390 |
Document ID | / |
Family ID | 48463668 |
Filed Date | 2018-10-04 |
United States Patent
Application |
20180282419 |
Kind Code |
A1 |
Urech; David ; et
al. |
October 4, 2018 |
Bispecific Constructs and Their Use in the Treatment of Various
Diseases
Abstract
The present invention relates to bispecific constructs that
specifically bind to immune effector cells and, simultaneously, to
IL23R-carrying target cells, as well as nucleic acids, vectors,
host cells, pharmaceutical compositions, and methods of production
and use thereof, including such bispecific constructs for use in
treating inflammatory and/or autoimmune diseases and/or cancer.
Inventors: |
Urech; David; (Jona, CH)
; Gunde; Tea; (Zurich, CH) ; Meyer; Sebastian;
(Eggenwil, CH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Numab Therapeutics AG |
Pfaffikon |
|
CH |
|
|
Family ID: |
48463668 |
Appl. No.: |
15/978390 |
Filed: |
May 14, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14889225 |
Nov 5, 2015 |
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PCT/EP2014/001282 |
May 12, 2014 |
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15978390 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61P 25/00 20180101;
C07K 2317/622 20130101; A61P 25/16 20180101; C07K 2317/56 20130101;
C07K 2317/626 20130101; A61P 27/02 20180101; A61P 37/06 20180101;
A61P 17/06 20180101; A61P 25/28 20180101; A61P 29/00 20180101; A61P
35/02 20180101; C07K 2317/55 20130101; A61P 9/10 20180101; A61P
35/00 20180101; C07K 16/2866 20130101; C07K 2317/569 20130101; A61P
1/04 20180101; A61P 3/10 20180101; C07K 2317/73 20130101; C07K
2317/92 20130101; C07K 2317/75 20130101; C07K 2317/33 20130101;
C07K 16/2809 20130101; A61P 19/02 20180101; C07K 2317/31
20130101 |
International
Class: |
C07K 16/28 20060101
C07K016/28 |
Foreign Application Data
Date |
Code |
Application Number |
May 10, 2013 |
EP |
13002500.0 |
Claims
1. A method of treatment of an inflammatory and/or autoimmune
disease or cancer comprising IL23R-expressing cells, comprising
administering to a subject an effective amount of a bispecific
construct comprising at least one first binding moiety and at least
one second binding moiety, wherein said first binding moiety
specifically binds to a first antigen present on a cytotoxic
effector T (Tc) cell, wherein said first antigen is CD3, and said
second binding moiety specifically binds to the IL23R present on
the surface of the IL23R-expressing cells, and wherein said first
binding moiety and said second binding moiety are antibody-based
binding moieties.
2. The method according to claim 1, wherein the inflammatory and/or
autoimmune disease is selected from the group consisting of
rheumatoid arthritis, ankylosing spondylitis, psoriasis, psoriatic
arthritis, ulcerative colitis, Crohn's disease, systemic lupus
erythematosus, juvenile diabetes, autoimmune uveitis, and multiple
sclerosis, Parkinson's disease, Alzheimer's disease, and
ischemia-reperfusion injury.
3. The method according to claim 1, wherein the cancer is selected
from the group consisting of colorectal cancer, lung cancer, breast
cancer, nasopharyngeal cancer, oral cancer, esophageal cancer,
pancreatic cancer, B-cell lymphomas, and T-cell lymphomas,
including adult T-cell lymphoma leukemia (ATLL), acute myeloid
lymphoma (AML), diffuse large B-cell lymphoma (DLBCL), follicular
lymphoma (FL), pediatric acute lymphoblastic lymphoma (B-ALL),
angioimmunoblastic T-cell lymphoma (AITL), anaplastic large-cell
lymphoma (ALCL), T-/natural killer-cell lymphomas, and peripheral
T-cell lymphoma (PTCL).
4. The method of claim 1, wherein the subject is a human
patient.
5. The method of claim 1, wherein the subject is a human patient,
which has a high Th17 response.
6. The method of claim 1, wherein said first binding moiety
specifically binds to the epsilon chain of CD3 (CD3.epsilon.).
7. The method of claim 1, wherein the construct allows for
efficient killing of said IL23R-expressing cells by the Tc
cell.
8. The method of claim 1, wherein said Tc cell is a stimulated or
an unstimulated Tc cell.
9. The method of claim 1, wherein said first and second binding
moieties are arranged relative to each other in such a manner that
the part of the first binding moiety recognizing CD3.epsilon. and
the part of the second binding moiety recognizing IL23R project,
relative to the center of the bispecific construct, outward in
essentially opposite directions.
10. The method of claim 1, wherein said bispecific construct is in
an antibody format selected from the group consisting of a
single-chain diabody (scDb), a tandem scDb (Tandab), a linear
dimeric scDb (LD-scDb), a circular dimeric scDb (CD-scDb), a
bispecific T-cell engager (BiTE; tandem di-scFv), a tandem
tri-scFv, a tri(a)body, bispecific Fab.sub.2, di-miniantibody,
tetrabody, scFv-Fc-scFv fusion, di-diabody, DVD-Ig, IgG-scFab,
scFab-dsscFv, Fv2-Fc, IgG-scFv fusions, including bsAb, Bs1Ab,
Bs2Ab, Bs3Ab, Ts1Ab, Ts2Ab, and Knob-into-Holes (KiHs) and
DuoBodies.
11. The method of claim 10, wherein said bispecific construct is a
single-chain diabody (scDb).
12. The method of claim 11, wherein the bispecific scDb comprises
two variable heavy chain domains (V.sub.H) or fragments thereof and
two variable light chain domains (V.sub.L) or fragments thereof
connected by linkers L1, L2 and L3 in the order
V.sub.HA-L1-V.sub.SB-L2-V.sub.HB-L3-V.sub.LA,
V.sub.HA-L1-V.sub.HB-L2-V.sub.SB-L3-V.sub.LA,
V.sub.LA-L1-V.sub.SB-L2-V.sub.HB-L3-V.sub.HA,
V.sub.LA-L1-V.sub.HB-L2-V.sub.SB-L3-V.sub.HA,
V.sub.HB-L1-V.sub.LA-L2-V.sub.HA-L3-V.sub.SB,
V.sub.HB-L1-V.sub.HA-L2-V.sub.LA-L3-V.sub.SB,
V.sub.SB-L1-V.sub.LA-L2-V.sub.HA-L3-V.sub.HB or
V.sub.SB-L1-V.sub.HA-L2-V.sub.LA-L3-V.sub.HB, wherein the V.sub.LA
and V.sub.HA domains jointly form the antigen binding site for
CD3.epsilon., and V.sub.SB and V.sub.HB jointly form the antigen
binding site for IL23R.
13. The method of claim 1, wherein the bispecific construct is SEQ
ID NO: 7, or a functionally active variant of the construct
according to SEQ ID NO: 7.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to bispecific constructs that
specifically bind to immune effector cells and, simultaneously, to
IL23R-carrying target cells, as well as nucleic acids, vectors,
host cells, pharmaceutical compositions, and methods of production
and use thereof, including such bispecific constructs for use in
treating inflammatory and/or autoimmune diseases and/or cancer.
BACKGROUND OF THE INVENTION
[0002] Interleukin (IL)-23 is a heterodimeric cytokine comprised of
two protein subunits, designated p40 and p19 for their approximate
molecular weights. The p40 protein is shared between IL-12 and
IL-23, whereas the p19 protein subunit is unique to IL-23. IL-23
signals through a two-chain receptor complex consisting of the
IL-12 receptor beta-1 (IL-12R[31) chain, which binds to p40, and a
unique IL-23 receptor chain (IL23R), which confers IL-23-specific
intracellular signaling.
[0003] IL-23 induces the differentiation of naive CD4+ T cells into
pathogenic IL-17-producing helper T (Th17 or Th.sub.IL-17) cells.
The IL-17 secreted by this distinct helper T cell subset is an
important effector cytokine during inflammation. Elevated IL-17
levels have been observed in target tissues of various autoimmune
diseases and inflammatory conditions, including rheumatoid
arthritis, inflammatory bowel diseases (i.e., Crohn's disease and
ulcerative colitis), and psoriasis. Therefore, IL-23 has been
implicated as a critical factor in inflammatory conditions and
autoimmune-mediated diseases.
[0004] Several approaches to target IL-23/IL-17 signaling have been
tested so far, including antibodies directed against IL-23 or the
IL-23 receptor, as potential therapeutic approaches for treating
inflammatory and autoimmune diseases. With respect to the use of
IL-23 as a target for potential pharmacological interventions,
various neutralizing antibodies directed to the p40 subunit of
IL-23 have been developed for potential use in the treatment of
autoimmune driven diseases. For example, the monoclonal antibody
known as "ustekinumab" (Janssen-Cilag) is an antibody that targets
the common p40 subunit of IL-12 and IL-23. It has been shown to be
effective in the treatment of psoriasis and psoriatic arthritis.
Another monoclonal antibody that targets the smaller p19 subunit of
IL-23 is described in EP 2 548 577.
[0005] With regard to strategies aimed at blocking the IL-23
receptor function by IL-23 receptor-targeting antibodies, WO
2004/042009 discloses the use of a monoclonal anti-IL-23 receptor
antibody or fragments thereof (Fv, Fab, Fab' and F(ab').sub.2) for
the treatment of an inflammatory disease associated with elevated
expression of IL-17. Moreover, WO 2008/106134 discloses the
generation of humanized antibodies, which recognize the IL23R chain
of the human IL-23 receptor, suitable for use in the treatment of
inflammatory and autoimmune disorders. These anti-IL23R antibodies
include, inter alia, antibodies conjugated to cytotoxic payloads
that can be used in immunotherapy to selectively target and kill
cells expressing IL23R on their surface.
[0006] A promising approach for the antibody-based treatment of
various cancer diseases is the redirection of immune effector cells
to specifically lyse target cells using bispecific antibodies. The
bispecific antibodies recognize a particular antigen on the surface
of a target cell and, simultaneously, an activating surface
molecule of an immune effector cell, such as a natural killer (NK)
cell or a cytotoxic T (Tc) cell, to thereby kill the target
cells.
[0007] The bispecific antibody concept is, for example, used in
cancer therapy where bispecific antibodies are employed that bind
to a cancer antigen on cancer cells and, simultaneously, to the
epsilon chain of CD3 presented on, for example, cytotoxic T cells.
A well-known example of such a bispecific antibody construct is
"blinatumomab", an antibody in the BiTE (bi-specific T cell
engager) format, for the treatment of non-Hodgkin's lymphoma and
acute lymphoblastic leukemia. Blinatumomab was developed by
Micromet and simultaneously binds to the cancer antigen CD19 as
well as to CD3 on the surface of cytotoxic T cells, thereby linking
these two cell types together and activating the cytotoxic T cell
to lyse the target cancer cell.
[0008] The hitherto most successful antibody-based approaches to
treat inflammatory and/or autoimmune diseases exploit mechanisms of
action that interfere with the interaction of cytokines and their
respective receptors in order to prevent signaling through cytokine
receptors. Examples include inhibition of TNF.alpha. (e.g.,
infliximab and adalimumab), inhibition of p40 (e.g., ustekinumab)
or inhibition of IL6R (e.g., tocilizumab). However, these
antibodies often still allow for the signaling through redundant
pathways. As a consequence, a significant number of patients cannot
be effectively treated. For example, up to 40% of the patients are
refractory to treatment with TNF.alpha. inhibiting antibodies.
[0009] Thus, there is still a need for new and improved treatment
strategies in the treatment of various diseases, such as
inflammatory and/or autoimmune diseases and cancer. In particular,
bispecific molecules for use in such treatments are required that
are stable, easy to produce, highly specific for a given target
antigen, and have a low immunogenicity.
SUMMARY OF THE INVENTION
[0010] The present invention meets the needs presented above by
providing a bispecific construct that specifically binds to an
immune effector cell, i.e. a cytotoxic effector T (Tc) cell and,
simultaneously, to a IL-23 receptor expressing target cell, e.g. a
pathogenic IL-17-producing helper T cell (Th17 cell), in order to
kill the IL-23 receptor expressing target cell.
[0011] In a first aspect, the present invention provides a
bispecific construct comprising at least one first binding moiety
and at least one second binding moiety for use in the treatment of
cancer comprising IL23R-expressing tumor cells, wherein said first
binding moiety specifically binds to a first antigen present on a
cytotoxic effector T (Tc) cell, and said second binding moiety
specifically binds to the IL-23 receptor specific subunit
(IL23R).
[0012] In a second aspect, the present invention provides a
bispecific construct comprising at least one first binding moiety
and at least one second binding moiety, wherein said first binding
moiety specifically binds to a first antigen present on a cytotoxic
effector T (Tc) cell, and said second binding moiety specifically
binds to the IL-23 receptor specific subunit (IL23R) present on the
surface of a target cell.
[0013] The present invention also provides, in further aspects, a
nucleic acid or nucleic acids encoding the bispecific construct of
the present invention, as well as a vector or vectors comprising
said nucleic acid or nucleic acids, and a host cell or host cells
comprising said vector or vectors.
[0014] Another aspect the present invention relates to a method for
producing the bispecific construct of the present invention,
comprising (i) providing a nucleic acid or nucleic acids according
to the present invention, or a vector or vectors according to the
present invention, expressing said nucleic acid or nucleic acids or
said vector or vectors and collecting said bispecific construct
from the expression system, or (ii) providing a host cell or host
cells of the present invention, culturing said host cell or host
cells, and collecting the bispecific construct from the cell
culture.
[0015] Yet another aspect of the present invention relates to a
pharmaceutical composition comprising the bispecific construct of
the present invention and a pharmaceutically acceptable
carrier.
[0016] In still another aspect, the present invention relates to
the use of a bispecific construct of the present invention in the
treatment of an inflammatory and/or autoimmune disease, or in a
method for the treatment of an inflammatory and/or autoimmune
disease, comprising administering to a subject an effective amount
of the bispecific construct of the present invention. Exemplary
inflammatory and/or autoimmune diseases include rheumatoid
arthritis, ankylosing spondylitis, psoriasis, psoriatic arthritis,
ulcerative colitis, Crohn's disease, systemic lupus erythematosus,
juvenile diabetes, autoimmune uveitis, multiple sclerosis,
Parkinson's disease, Alzheimer's disease, and ischemia-reperfusion
injury.
[0017] Particular embodiments of the present invention are set
forth in the appended dependent claims.
FIGURES
[0018] FIG. 1: A: IL23 signaling and Th1 antitumor response; B:
proposed mechanisms of bispecific anti-IL23R.times.CD3.epsilon.
antibody interactions.
[0019] FIG. 2: Expression of IL23R on colon cancer cell-lines.
IL23R expression was detected by a primary goat polyclonal
anti-IL23R antibody and a PE-labeled anti-goat antibody. Solid
lines, IL23R expression; dashed lines, isotype control. X-axis, PE
intensity; Y-axis, cell counts.
[0020] FIG. 3: IL23R expression on lung adenocarcinoma cell-line.
IL23R expression was detected by a primary goat polyclonal
anti-IL23R antibody and a PE-labeled anti-goat antibody. Solid
lines, IL23R expression; dashed lines, isotype control. X-axis, PE
intensity; Y-axis, cell counts.
[0021] FIG. 4: IL23R expression on lymphoma/leukemia cell-lines.
IL23R expression was detected by a primary goat polyclonal
anti-IL23R antibody and a PE-labeled anti-goat antibody. Solid
lines, IL23R expression; dashed lines, isotype control. X-axis, PE
intensity; Y-axis, cell counts.
[0022] FIG. 5: Phylogenetic tree generated by aligning the unique
CDR sets with the Neighbor Joining algorithm of COBALT.
[0023] FIG. 6: Thermal unfolding of PRO165 by differential scanning
fluorimetry. Duplicate measurement of temperature induced protein
unfolding normalized fluorescence signal.
[0024] FIG. 7. T cell driven lysis of DLD-1 colon carcinoma cells
induced by PRO165. Quantification of early apoptotic and necrotic
DLD-1 cells.
DETAILED DESCRIPTION OF THE INVENTION
[0025] In a first aspect, the present invention provides a
bispecific construct comprising at least one first binding moiety
and at least one second binding moiety for use in the treatment of
cancer comprising IL23R-expressing tumor cells, wherein said first
binding moiety specifically binds to a first antigen present on a
cytotoxic effector T (Tc) cell, and said second binding moiety
specifically binds to the IL-23 receptor specific subunit
(IL23R).
[0026] Within the meaning of the present invention, the term
"construct" refers to any chemical entity so long as it exhibits
the desired binding activity. Thus, the term "construct" is used in
the broadest sense and specifically covers protein-based molecules,
including recombinant antibodies and fragments thereof comprising
one or more antibody-based domains or binding fragments thereof.
Specific examples include, but are not limited to, monoclonal
chimeric antibodies, humanized antibodies, single-chain diabodies
and the like. Furthermore, the term "comprise" as used within the
present invention, for example in conjunction with the term
"construct", encompasses both "includes" and "consists of".
[0027] The term "bispecific", as used herein, is intended to refer
to a construct having two different antigen specificities and,
optionally, other binding moieties that bind to their respective
binding partners, such as a moiety that binds to an Fc receptor or
a tag for detection and/or purification. This means that a
bispecific construct is capable of simultaneously binding to at
least one antigen "A" and at least one antigen "B", wherein A and B
are not the same. Thus, whilst having two different antigen
specificities, a bispecific construct of the present invention does
not necessarily have only two binding moieties, one for each
targeted antigen, but may also include more than two binding
moieties. Furthermore, the term "antigen", as used herein, is to be
interpreted in a broad sense and includes any target moiety that is
bound by the binding moieties of the bispecific construct of the
present invention.
[0028] As used in the present invention, the terms "specific" or
"specifically" are intended to mean that the first and second
binding moieties are able to discriminate between their respective
target molecules (i.e. between the first and second antigen) and/or
one or more reference molecule(s). Thus, in its broadest sense,
"specific binding" or "specifically binding" refers to the first
and second binding moieties' ability to discriminate between the
first antigen on the surface of a Tc cell and the IL23R second
antigen on the surface of a target cell and/or between other target
molecules that are related to or not related to the first antigen
and/or the second antigen (i.e., IL23R).
[0029] The binding specificity of a specific binding moiety can be
determined as known in the art using, for example, surface plasma
resonance (SPR), western blot, enzyme-linked immunosorbent assay
(ELISA), radioimmunoassay (RIA or IRMA), enhanced chemiluminescence
(ECL), and peptide scan analysis.
[0030] If an ELISA assay is used, the scoring can be carried out by
means of a standard color development reaction, for example by
using horseradish peroxidase (HRP)-conjugated second antibodies in
a HRP, H202, tetramethyl benzidine system. The optical density of
the color development in the reaction vessel (e.g. well) at a given
wavelength is a measure of the binding specificity. A typical
background signal (negative reaction) may be about 0.1 OD, whereas
a typical signal for a positive reaction may be about 1.0 OD or
higher, resulting in a signal to noise ratio of 10:1 or higher.
Typically, the determination of the binding specificity is carried
out using a set of about three to five unrelated biomolecules, such
as milk powder, BSA, transferrin and the like, rather than using
only a single reference biomolecule.
[0031] In particular, the present invention relates to a method for
the treatment of cancer comprising IL23R-expressing tumor cells,
comprising administering to a subject, particularly a human
patient, an effective amount of the bispecific construct of the
present invention.
[0032] The term "effective amount" is defined as set out below in
Section [0085]. Typically, an effective amount of the bispecific
construct of the present invention is administered in form of the
above-described pharmaceutical composition. Suitable administration
routes include, but are not limited to, topical and parenteral
administration, in particular subcutaneous and intravenous
injection. The administration regimen is not particularly limited
and includes, for example, continuous infusion over one week, two
weeks or four weeks.
[0033] The cancer to be treated includes, but is not limited to,
colorectal cancer, lung cancer, breast cancer, nasopharyngeal
cancer, oral cancer, esophageal cancer, pancreatic cancer, B-cell
lymphomas, and T-cell lymphomas, including adult T-cell lymphoma
leukemia (ATLL), acute myeloid lymphoma (AML), diffuse large B-cell
lymphoma (DLBCL), follicular lymphoma (FL), pediatric acute
lymphoblastic lymphoma (B-ALL), angioimmunoblastic T-cell lymphoma
(AITL), anaplastic large-cell lymphoma (ALCL), T-/natural
killer-cell lymphomas, and peripheral T-cell lymphoma (PTCL). In
particular embodiments the cancer is selected from colorectal
cancer, lung cancer, breast cancer, nasopharyngeal cancer, oral
cancer, esophageal cancer, B-cell lymphomas, and T-cell lymphomas
such as adult T-cell lymphoma leukemia (ATLL), angioimmunoblastic
T-cell lymphoma (AITL), anaplastic large-cell lymphoma (ALCL),
T-/natural killer-cell lymphomas, and peripheral T-cell lymphoma
(PTCL).
[0034] The balance between interleukin (IL)-23 and IL-12 plays an
important role in regulating the anti-tumor immune response. IL-23
and IL-12 are heterodimeric cytokines that share one of their
domains (p40). While IL-12--consisting of the two subunits p35 and
p40--has been found to have antitumor effects, IL-23 that is
composed of p40 and p19, seems to promote growth of certain tumors
by direct effects on tumor cells and by indirect mechanisms
creating a tumor supportive inflammatory microenvironement. IL-12
drives the development of IFN-.gamma. producing Th1 cells, which
are crucial for the antitumor immunity (Dunn, G. P. et al. 2006.
Nat. rev. Immunol:6; 836-848; Colombo, M. P. and Trinchieri,
G.2002.Cytokine Growth Factor Rev; 13:155-168). IL-12 and
IFN-.gamma. are able to inhibit the expansion of intratumoral T
regulatory cells (Tregs) that antagonize the activity of Th1 cells,
as well as angiogenesis in the tumor microenvironment, thus
enhancing tumor control (Cao, X et al.2009.Cancer Res;
69:8700-8709). In line with a converse effect of IL-23 in the tumor
microenvironment, IL-23 suppresses IL-12-dependent IFN-y secretion
in T cells (Sieve, A. N. et al. 2010.Eur. J. Immunol; 40;
2236-2247). In the gut, IL-23 produced by dendritic cells (DCs) in
response to microbial products, cellular stress and cell death, may
drive the formation of Th17 cells instead of an antitumor Th1
response. These Th17 cells in turn also produce IL-23, which may
inhibit the immune surveillance activity mediated by cytotoxic T
cells by potentially preventing their ability to infiltrate into
the tumor (Ngiow, S. F.2013.Trend in Immunology; 34:548-555) and to
affect antitumor and antimetastatic functions of NK cells (Teng, M.
W. et al. 2010PNAS; 107:8328-8333). In line with the view that
IL-23 signaling may have effects supporting tumor formation and/or
growth in certain tumors is the finding that mice deficient only in
IL-12 signaling show increased tumor growth, while mice deficient
for both, IL-12 and IL-23 signaling, show no increased risk of
developing tumors (Street, S. E. et al.2002. J. Exp. Med;
196:129-134; Airoldi, I, et al. 2005.Blood; 106:3846-3853).
Furthermore, mice specifically deficient for IL-23 signaling--but
not for IL-12 signaling--were found to be almost completely
resistant to tumor formation and showed attenuated tumor growth
(Langowski, J. L. etal.2008. Nature; 442:461-465; Teng, M. W. et
al. 2010PNAS; 107:8328-8333). In a recent study it was further
found that the coadministration of an anti-CD40 antibody
stimulating T-cells together with an anti-IL-23 antibody
attenuating the Th17 response showed better efficacy as compared to
either antibody alone (von Scheidt, B. et al. 2014.Cancer Res;
DOI:10.1158/0008-5472.CAN-13-1646), possibly by shifting the
balance from Th17 to Th1. In the human situation, independent
clinical studies have reported that serum concentrations of IL-23
are increased in cancer patients in comparison with healthy
individuals (Li, J. et al.2012. PLoS ONE; 7:e46264; Gangemi, S. et
al.2012. J. Cell. Biochem; 113:2122-2125; Ljujic, B. et al.2010.
Arch. Med. Res; 41:182-189; He, S. et al. 2011.Int. J. Mol. Sci;
12:7424-7437; Fukuda, M, et al.2010.Int. J. Oncol; 36:1355-1365).
For example in pancreatic cancer, elevated IL-23 levels correlated
with disease stage and in breast cancer with poor prognosis (He, S.
et al. 2011.Int. J. Mol. Sci; 12:7424-7437). In primary
hepatocellular carcinoma (HCC) higher IL-23 levels in the cancer
microenvironment have been associated with poor prognosis. Also in
colorectal cancer serum IL-23 levels were increased in patients as
compared to healthy donors (Stanilov, N. S.2009.Labmedicine;
41:159-163). Further, Th17 gene expression profiles as well as Th17
cell infiltrations in colorectal cancer tissue samples were
associated with drastically worse prognosis as opposed to Th1 gene
expression or Th1 cell infiltration (Tosolini et al, Cancer Res
2011; 71:1263-1271). Collectively, these data suggest that IL-23
promotes tumorigenesis by driving protumor inflammation to suppress
antitumor effector cells.
[0035] Human IL23R is predominantly found in activated memory T
cells, natural killer (NK) cells, and innate lymphoid cells (ILCs),
and at lower levels on monocytes, macrophages, and dendritic cells
(DCs). Recently, direct effects of interleukin IL-23 on tumor cells
have been described, suggesting that IL23R is expressed also on
certain tumors. For example IL-23 was shown to have
pro-proliferative effects on human oral squamous cell carcinoma
(SSC) cell lines (Fukuda, M et al.2010. Int. J. Oncol;
36:1355-1365; Fukuda, M et al.2010. Mol. Med. Rep,; 3:89-93) and
non-small cell lung cancer (NSCLC) cell lines (Baird, A. M. et
al.2013. Lung Cancer; 79:83-90). Using genome-wide association
studies, two sequence variants of IL23R have been associated with
the risk of several solid cancers and the same polymorphisms have
been found to predispose individuals to an increased risk of acute
myeloid leukemia (AML) (Xu, Y, et al.2013.J Gastroenterol;
48:125-131; Chu, H. et al.2012.Int. J. cancer; 130:1093-1097; Chen,
J. et al.2010. mol. Carcinog; 49:862-868; Qian, X. et al.2013. PLoS
ONE; 8:e55473). IL23R expression was further found to be
upregulated in primary tumor tissue of small cell lung cancer
(SCLC), in lung andenocarcinoma (Li, J. et al.2013. Carcinog;
34:658-666), in follicular lymphoma (FL) and diffuse large B cell
lymphoma (DLBCL) (Cocco et al.Leukemia.2012:26:1365-1374), in
pediatric B-ALL (Cocco et al.Blood.2010; 116:3887-3898) as well as
in colorectal carcinoma (CRC) (Lan et al, Int J Colorectal Dis
2011; 26:1511-1518; Suzuki et al, Oncology Letters 2012;
4:199-204). In CRC a correlation between expression level and
severity/metastasis was found (Carlsson et al, Br J Cancer 2012;
106:517-524).
[0036] Taken together, IL-23 seems to create an inflammatory
microenvironment that on one hand favors tumor formation, growth
and metastasis and on the other hand supports tumor immune escape
by attenuating the Th1 antitumor response (see FIG. 1A).
Preclinical studies with co-administration of anti-CD40 and
anti-IL-23 antibodies have demonstrated that this "push" (anti-CD40
driven activation of T cells) and "pull" (anti-IL-23 driven
attenuation of Th17 cells) is effective in certain tumor models.
However, this approach does not specifically target cancer cells.
Thus certain cancer cells are still likely to escape the enhanced
Th1 response. And further, systemic activation of Th1 cells may
lead to adverse effect, such as enhancing inflammatory processes.
Other approaches using bispecific antibodies redirecting T cells to
lyse cancer cells have demonstrated efficacy in different tumor
models, also in solid tumors such as colorectal cancer
(Lutterbuese, R. et al.2010.PNAS; 107:12605-12610; Osada T. et al.
2010; British J Cancer; 102:124-133).
[0037] Here we present a novel approach aiming at optimally
balancing efficacy and safety, by specifically targeting cancer
cells on one hand and by locally stimulating the anti-tumor
immune-response on the other hand. To achieve this, a bispecific
anti-IL23R.times.CD3.epsilon. antibody is employed that acts
through the mechanisms, illustrated in FIG. 1B: [0038] a)
Redirecting CD3+ cytotoxic T cells to lyse IL23R expressing tumors;
[0039] b) Stimulating CD3+ Th1 cells specifically in the tumor
microenvironment, as binding to target cells and consequently
cross-linking of CD3.epsilon. binding domains is required for T
cell stimulation; [0040] c) Redirecting CD3+ cytotoxic T cells to
lyse IL23R expressing Th17 cells, thereby eliminating a major
source of Th1 inhibitory cytokines; [0041] d) Redirecting CD3+
cytotoxic T cells to lyse IL23R expressing regulatory T (Treg)
cells that inhibit the Th1 anti-tumor response; and [0042] e)
Optionally: blocking IL-23 signaling by competing with IL-23
binding to its receptor IL23R.
[0043] In particular embodiments, said human patient is a patient,
which has a high Th17 response.
[0044] In the context of the present invention, the term "high Th17
response" refers to a situation, where a patient either shows
increased Th17 gene expression or increased counts of Th17 cells.
An increased Th17 gene expression may be shown by increased levels
of Th17 gene mRNA in the tumor tissue when compared to normal
distant control tissue. In colorectal cancer such increase is at
least 2-fold, particularly 4-fold and most particularly 5- to
6-fold for the genes IL17A and RORC (see Tosolini et al., Cancer
Res 2011; 71:1263-1271) between tumor tissue and normal distant
mucosa. An increased count of Th17 cells may be seen in the tumor
tissue or in the tumor adjacent tissue compared to distant control
tissue. In colorectal cancer, such increased counts are observed in
the center or at the invasive margin, particularly in both the
center and the invasive margin of the tumor (see Tosolini et al.,
loc. cit.)
[0045] In a second aspect, the present invention relates to a
bispecific construct having at least one first binding moiety and
at least one second binding moiety. The first and second binding
moieties specifically bind to a first antigen and a second antigen,
respectively. The first antigen is an antigen present on the
surface of an immune effector cell, namely a cytotoxic effector T
(Tc) cell (also known as cytotoxic T lymphocyte (CTL) or T killer
cell). The second antigen is the IL-23 receptor specific subunit,
IL23R, present on the surface of a target cell.
[0046] Within the present invention, one target cell type is
typically a pathogenic cell, in particular a pathogenic T cell,
more particularly a T cell expressing the transcription factor
ROR.gamma.(t). ROR.gamma.(t) promotes thymocyte differentiation
into pro-inflammatory Th17 cells and also plays a role in
inhibiting apoptosis of undifferentiated T cells and promoting
their differentiation into Th17 cells, possibly by down-regulating
the expression of the Fas ligand and IL-2, respectively. In
particular embodiments, the cells are selected from the group
consisting of IL-17 producing T cells (Th17 cells), .gamma..delta.
T cells, natural killer T (NKT) cells and invariant natural killer
(iNK) cells. Most particularly, the target cells within the present
invention are selected from Th17 cells and .gamma..delta. T
cells.
[0047] Another target cell type within the present invention is a
tumor cell, particularly a tumor cell expressing IL23R. IL23R
expression has for example been shown for epithelial cancers such
as colon carcinoma (CRC), small-cell lung cancer (SCLC),
adenocarcinoma (AC) of the lung, as well as on various B- and
T-cell tumors, exemplified by diffuse large B-cell lymphoma
(DLBCL), follicular lymphoma (FL), pediatric B-ALL and acute
myeloid lymphoma (AML).
[0048] In particular such embodiments, said bispecific construct
has at least one first binding moiety directed against an antigen
present on the surface of an immune effector cell, namely a
cytotoxic effector T (Tc) cell (also known as cytotoxic T
lymphocyte (CTL) or T killer cell), and at least a second binding
moiety directed against the IL-23 receptor specific subunit, IL23R,
present on the surface of a tumor cell, wherein said bispecific
construct is also able to eliminate Th17 cells and to stimulate a
Th1 response. In particular such embodiments, said first antigen is
CD3, particularly CD3.epsilon..
[0049] The first and second binding moieties are not structurally
limited so long as they specifically bind to the desired first and
second antigens. However, the first and second binding moieties
generally consist of or are formed of one or more oligo- or
polypeptides or parts thereof. Particularly, the first and second
binding moieties are antibody-based binding moieties, which
typically comprise at least one antibody variable domain or binding
fragment thereof.
[0050] In a particular embodiment of the present invention, the
first binding moiety specifically binds to a first antigen selected
from CD3 and CD28. The CD3 protein is associated with the T cell
receptor (TCR) and required for T cell activation. CD3 is a complex
of one CD3.gamma., one CD3.delta. and two CD3.epsilon. chains
which, together with the TCR and the .xi.-chain, form the TCR
receptor complex. CD28 is one of the molecules expressed on T cells
that provide co-stimulatory signals required for T cell activation.
Stimulation through CD28 can provide a potent co-stimulatory signal
to T cells.
[0051] In a particular embodiment of the present invention, the
first binding moiety binds specifically to CD3, more particularly
to the epsilon chain of CD3 (CD3.epsilon.), and most particularly
to an agonistic epitope of CD3.epsilon.. The term "agonistic
epitope", as used herein, means (a) an epitope that, upon binding
of the bispecific construct of the present invention, optionally
upon binding of several bispecific constructs on the same cell,
allows said bispecific constructs to activate TCR signaling and
induce T cell activation, and/or (b) an epitope that is solely
composed of amino acid residues of the epsilon chain of CD3 and is
accessible for binding by the bispecific construct of the present
invention, when presented in its natural context on Tc cells (i.e.
surrounded by the TCR, the CD3.gamma. chain, etc.), and/or (c) an
epitope that, upon binding of the bispecific construct of the
present invention, does not lead to stabilization of the spatial
position of CD3.epsilon. relative to CD3.gamma..
[0052] In another particular embodiment of the present invention,
instead of binding to Tc cells, the first binding moiety
specifically binds to a component of the complement system, such as
C1q. C1q is a subunit of the Cl enzyme complex that activates the
serum complement system.
[0053] In an alternative embodiment, the present invention also
contemplates the use of a first binding moiety that specifically
binds to an Fc receptor, in particular to an Fc gamma receptor
(Fc.gamma.R). The Fc.gamma.R may be a Fc.gamma.RIII present on the
surface of natural killer (NK) cells or one of Fc.gamma.RI,
Fc.gamma.RIIA, Fc.gamma.RIIB1, Fc.gamma.RIIB2, and Fc.gamma.RIIIB
present on the surface of macrophages, monocytes, neutrophils
and/or dendritic cells.
[0054] In such embodiment, the first binding moiety particularly is
an Fc region or functional fragment thereof. In the present
context, a "functional fragment" refers to a fragment of an
antibody Fc region that is still capable of binding to an FcR, in
particular to an Fc.gamma.R, with sufficient specificity and
affinity to allow an Fc.gamma.R bearing effector cell, in
particular a macrophage, a monocyte, a neutrophil and/or a
dendritic cell, to kill the target cell by cytotoxic lysis or
phagocytosis. Particularly, a functional Fc fragment is capable of
competitively inhibiting the binding of the original, full-length
Fc portion to an FcR such as the activating Fc.gamma.RI.
Particularly, a functional Fc fragment retains at least 30%, 40%,
50%, 60%, 70%, 80%, 90% or 95% of its affinity to an activating
Fc.gamma.R.
[0055] Within such embodiment of the present invention, the Fc
region or functional fragment thereof is particularly an enhanced
Fc region or functional fragment thereof. The term "enhanced Fc
region", as used herein, refers to an Fc region that is modified to
enhance Fc receptor-mediated effector-functions, in particular
antibody-dependent cell-mediated cytotoxicity (ADCC),
complement-dependent cytotoxicity (CDC), and antibody-mediated
phagocytosis. This can be achieved as known in the art, for example
by altering the Fc region in a way that leads to an increased
affinity for an activating receptor (e.g. Fc.gamma.RIIIA (CD16A)
expressed on natural killer (NK) cells) and/or a decreased binding
to an inhibitory receptor (e.g. Fc.gamma.RIIB1/B2 (CD32B)).
[0056] Suitable alterations within the present invention include
altering glycosylation patterns, in particular afucosylation (also
referred to as "defucosylation"), mutations (point mutations,
deletions, insertions) and fusions with oligo- or polypeptides.
Known techniques for altering glycosylation patterns include
overexpression of heterologous
.beta.1,4-N-acetylglucosaminyltransferase III in the
antibody-producing cell (known as the Glycart-Roche technology) and
knocking out of the gene encoding .alpha.-1,6-fucosyltransferase
(FUT8) in the antibody-producing cell (the Potelligent technology
from Kyowa Hakko Kirin). Specific examples of enhancing mutations
in the Fc part include those described in Shields et al., J. Biol.
Chem. 276:6591-6604 (2001), which is incorporated herein in its
entirety.
[0057] In accordance with the present invention, the bispecific
construct is particularly designed in such a way that the killing
of IL23R-expressing target cells by Tc cells is highly efficient.
Such efficient killing generally involves the ability of the
bispecific construct to effectively redirect Tc cells to lyse
IL23R-expressing target cells. The term "efficient", as used
herein, means that the bispecific construct of the present
invention typically shows an in vitro EC.sub.50 ranging from 10 to
500 ng/ml, and is able to induce redirected lysis of about 50% of
the target cells through Tc cells at a ratio of Tc cells to target
cells of from 1:1 to 50:1, particularly from 1:1 to 15:1, more
particularly from 2:1 to 10:1. As used herein above and below, the
terms "about" and "approximately" refer to .+-.10% of the indicated
value or range.
[0058] Furthermore, the bispecific construct of the present
invention is particularly capable of cross-linking a stimulated or
an (otherwise) unstimulated Tc cell and the target cell in such a
way that the target cell is lysed. This offers the advantage that
no generation of target-specific T cell clones or common antigen
presentation by dendritic cells is required for the bispecific
construct to exert its desired activity. In fact, the bispecific
construct of the present invention is particularly capable of
redirecting Tc cells to lyse the target cells in the absence of
other activating signals. More particularly, if the first binding
moiety of the bispecific construct specifically binds to CD3,
particularly to CD3.epsilon., signaling through CD28 and/or IL-2 is
not required for redirecting Tc cells to lyse the target cells. The
high potential to activate non-target specific and/or unstimulated
Tc cells is considered to be an important feature of the bispecific
construct of the present invention and is believed to contribute to
the efficient killing of target cells.
[0059] The present invention further contemplates that the first
and second binding moieties are particularly arranged relative to
each other in such a manner that the bispecific construct
preferentially binds to the first antigen present on a Tc cell and,
simultaneously, to the second antigen (i.e., IL23R) present on the
target cell, but is essentially not capable of simultaneous binding
to a single cell that co-expresses both the first antigen and IL23R
(e.g. an IL-17 expressing cytotoxic (Tc17) cell).
[0060] Methods for measuring the preference of the bispecific
construct to simultaneously bind to two cells are within the normal
capabilities of a person skilled in the art. For example, the
bispecific construct of the present invention may be contacted with
a mixture of CD3.sup.+/IL23R.sup.- cells and CD3.sup.+/IL23R.sup.+
cells or with a mixture of CD3.sup.+/IL23R.sup.- cells and
CD3.sup.-/IL23R.sup.+ cells. The number of bispecific
construct-positive single cells and the number of cells crosslinked
by bispecific constructs may then be assessed by microscopy or
fluorescence-activated cell sorting (FACS) as known in the art.
About the same number of observed bispecific cross-linked cells in
both set-ups indicate that the bispecific construct of the present
invention does not, or does essentially not, bind to a single
target cell exhibiting both the CD3 and IL23R antigen on its
surface. Alternatively, the apparent binding activity avidity may
be determined. If simultaneous binding to a single target cell is
not, or is essentially not, possible, the apparent binding activity
of the bispecific construct for IL23R.sup.+/CD3.sup.- or
IL23R.sup.-/CD3.sup.+ cells on one side and IL23R.sup.+/CD3.sup.+
cells on the other side will be about the same. If, however,
simultaneous binding to a single target cell is possible, the
apparent binding activity of the bispecific construct for
L23R.sup.-/CD3.sup.+ cells will be higher than that for
L23R.sup.-/CD3.sup.+ or L23R.sup.-/CD3.sup.+ cells due to avidity
effects.
[0061] In a particular embodiment of the present invention, the
bispecific construct has a structure where the first and second
binding moieties are arranged relative to each other in such a
manner that the part of the first binding moiety recognizing the
first antigen and the part of the second binding moiety recognizing
the second antigen project, relative to the center of the
bispecific construct, outward in essentially opposite directions.
The term "center" particularly relates to the center of geometry
(COG). Without being bound by any theory, it is believed that this
structure of the bispecific construct of the present invention
avoids the undesired double-binding to a single target cell as
outlined above. The term "essentially", as used in the present
context, means that said part of the first binding moiety and said
part of the second moiety are arranged, relative to the center of
the bispecific construct, at an angle of 135.degree. or more up to
180.degree..
[0062] The structure of the bispecific construct is particularly
also characterized in that the angle a between a first vector v1
from the center of geometry (COG) of the entire bispecific
construct to the COG of the first paratope of the first binding
moiety and a second vector v2 from the COG of the entire bispecific
construct to the COG of the second paratope of the second binding
moiety is approximately within the range of
135.degree.<.alpha.<180.degree., more particularly within the
range of 150.degree.<.alpha.<180.degree., and most
particularly within the range of
160.degree.<.alpha.<180.degree.. The term "paratope", as used
herein, refers to the portions of the first and second binding
moieties that directly interact with the first and second antigens,
respectively.
[0063] In the context of the present invention, the first binding
moiety and/or the second binding moiety is an antibody-based
binding moiety, particularly an antibody-based binding moiety
comprising a heavy chain variable domain (VH) or binding fragment
thereof, more particularly an antibody-based binding moiety
comprising a heavy chain variable domain (VH) or binding fragment
thereof and a light chain variable domain (VL) or binding fragment
thereof. The term "binding fragment", as used herein, refers to a
portion of a given domain, region or part, which is (either alone
or in combination with another domain, region or part thereof)
still functional, i.e. capable of binding to the first or second
antigen recognized by the bispecific construct.
[0064] Typically, a binding fragment within the meaning of the
present invention retains at least 10% of its native antigen
binding activity (i.e. of its antigen binding activity as a
monospecific construct) when comprised in a bispecific construct of
the present invention. Particularly, a binding fragment retains at
least 25%, 50%, 60%, 70%, 80%, 90%, 95%, or 99% of its native
antigen binding activity, or maintains or even exceeds the full
native antigen binding activity, although any binding fragment with
sufficient affinity to exert the desired biological effect (i.e.
lysing/killing of target cells by Tc cells) will be useful. It is
also intended that a "binding fragment" within the meaning of the
present invention includes variants having conservative amino acid
substitutions that retain their binding activity to the extent
defined above and, particularly, do not substantially alter their
binding or biological activity.
[0065] In another particular embodiment of the present invention,
the bispecific construct is an antibody format selected from the
group consisting of a single-chain diabody (scDb), a tandem scDb
(Tandab), a linear dimeric scDb (LD-scDb), a circular dimeric scDb
(CD-scDb), a bispecific T-cell engager (BiTE; tandem di-scFv), a
tandem tri-scFv, a tri(a)body, bispecific Fab2, di-miniantibody,
tetrabody, scFv-Fc-scFv fusion, di-diabody, DVD-Ig, IgG-scFab,
scFab-dsscFv, Fv2-Fc, IgG-scFv fusions, such as bsAb (scFv linked
to C-terminus of light chain), Bs1Ab (scFv linked to N-terminus of
light chain), Bs2Ab (scFv linked to N-terminus of heavy chain),
Bs3Ab (scFv linked to C-terminus of heavy chain), Ts1Ab (scFv
linked to N-terminus of both heavy chain and light chain), Ts2Ab
(dsscFv linked to C-terminus of heavy chain), and Knob-into-Holes
(KiHs) (bispecific IgGs prepared by the KiH technology) and
DuoBodies (bispecific IgGs prepared by the Duobody technology).
Particularly suitable for use herein is a single-chain diabody
(scDb), in particular a bispecific monomeric scDb.
[0066] The bispecific scDb, in particular the bispecific monomeric
scDb, particularly comprises two variable heavy chain domains (VH)
or fragments thereof and two variable light chain domains (VL) or
fragments thereof connected by linkers L1, L2 and L3 in the order
VHA-L1-VLB-L2-VHB-L3-VLA, VHA-L1-VHB-L2-VLB-L3-VLA,
VLA-L1-VLB-L2-VHB-L3-VHA, VLA-L1-VHB-L2-VLB-L3-VHA,
VHB-L1-VLA-L2-VHA-L3-VLB, VHB-L1-VHA-L2-VLA-L3-VLB,
VLB-L1-VLA-L2-VHA-L3-VHB or VLB-L1-VHA-L2-VLA-L3-VHB, wherein the
VLA and VHA domains jointly form the antigen binding site for the
first antigen, and VLB and VHB jointly form the antigen binding
site for IL23R.
[0067] The linker L1 particularly is a peptide of 2-10 amino acids,
more particularly 3-7 amino acids, and most particularly 5 amino
acids, and linker L3 particularly is a peptide of 1-10 amino acids,
more particularly 2-7 amino acids, and most particularly 5 amino
acids. The middle linker L2 particularly is a peptide of 10-40
amino acids, more particularly 15-30 amino acids, and most
particularly 20-25 amino acids.
[0068] In a particular embodiment of the present invention, the VH
domain of the first and second antibody-based binding moieties of
the bispecific construct comprises rabbit heavy chain
complementarity determining regions (CDRs) grafted onto human heavy
chain framework (FW) regions, and the VL domain of the first and
second antibody-based binding moieties of the bispecific construct
comprises rabbit light chain CDRs grafted onto human light chain FW
regions.
[0069] The heavy chain and light chain CDRs of the first
antibody-based binding moiety are particularly derived from a
rabbit antibody obtained by immunization of a rabbit with the
full-length epsilon chain of human CD3 the full-length, CD28 or the
full-length C1q. The immunization with the full-length chain of
CD3.epsilon., CD28 or C1q is suitably conducted by DNA immunization
of a rabbit with a plasmid encoding the full-length chain of human
CD3.epsilon., CD28 or C1q, or, alternatively, with the purified
extracellular domain of the epsilon chain of CD3, or with the
purified extracellular chain of CD28, or with the purified C1q.
Further, the heavy chain and light chain CDRs of the second
antibody-based binding moiety are particularly derived from a
rabbit antibody obtained by immunization of a rabbit either with
the purified extracellular domain of IL23R or with a plasmid
expressing the full-length IL23R.
[0070] The bispecific constructs of the present invention can be
produced using any convenient antibody manufacturing method known
in the art (see, e.g., Fischer, N. & Leger, O., Pathobiology
74:3-14 (2007) with regard to the production of bispecific
constructs; Hornig, N. & Farber-Schwarz, A., Methods Mol. Biol.
907:713-727, 2012, and WO 99/57150 A2 with regard to bispecific
diabodies and tandem scFvs). In addition, exemplary anti-IL23R and
anti-CD3.epsilon. antibody sequences are disclosed in EP 2 395 025
and EP 1 348 715, respectively. Specific examples of suitable
methods for the preparation of the bispecific construct of the
present invention further include, inter alia, the Genmab (see
Labrijn et al., Proc. Natl. Acad. Sci. USA 110:5145-5150 (2013))
and Merus (see de Kruif et al., Biotechnol. Bioeng. 106:741-750
(2010)) technologies. Methods for production of bispecific
antibodies comprising a functional antibody Fc part are also known
in the art (see, e.g., Zhu et al., Cancer Lett. 86:127-134 (1994));
and Suresh et al., Methods Enzymol. 121:210-228 (1986)).
[0071] These methods typically involve the generation of monoclonal
antibodies, for example by means of fusing myeloma cells with the
spleen cells from a mouse that has been immunized with the desired
antigen using the hybridoma technology (see, e.g., Yokoyama et al.,
Curr. Protoc. Immunol. Chapter 2, Unit 2.5, 2006) or by means of
recombinant antibody engineering (repertoire cloning or phage
display/yeast display) (see, e.g., Chames & Baty, FEMS
Microbiol. Letters 189:1-8 (2000)), and the combination of the
antigen-binding domains or fragments or parts thereof of two
different monoclonal antibodies to give a bispecific construct
using known molecular cloning techniques.
[0072] The bispecific constructs of the present invention are
particularly humanized in order to reduce immunogenicity and/or to
improve stability. Techniques for humanization of antibodies are
well-known in the art. For example, one technique is based on the
grafting of complementarity determining regions (CDRs) of a
xenogeneic antibody onto the variable light chain VL and variable
heavy chain VH of a human acceptor framework (see, e.g., Jones et
al., Nature 321:522-525 (1986); and Verhoeyen et al., Science
239:1534-1536 (1988)). In another technique, the framework of a
xenogeneic antibody is mutated towards a human framework. In both
cases, the retention of the functionality of the antigen-binding
portions is essential (Kabat et al., J. Immunol. 147:1709-1719
(1991)).
[0073] The bispecific constructs of the present invention may
alternatively comprise one or more binding moieties based on
non-antibody based binding domains. Specific examples of suitable
methods for the preparation of the bispecific construct of the
present invention further include, inter alia, the DARPin
technology (Molecular Partners AG), the adnexin technology
(Adnexus), the anticalin technology (Pieris), and the Fynomer
technology (Covagen AG).
[0074] In a particular embodiment of the present invention, the
bispecific construct is PRO165 (SEQ ID NO: 7), or a functionally
active variant of PRO165.
[0075] In the context of the present invention, the term
"functionally active variant of PRO165" refers to a bispecific
construct based on the VL and VH regions of PRO165, wherein (i)
said bispecific construct maintains the functional activity of
PRO165, i.e. wherein a first VH/VL pair specifically binds to
CD3.epsilon., and wherein a second VH/VL pair specifically binds to
the IL-23 receptor specific subunit (IL23R), and wherein (ii) said
VL and VH regions comprise at least one sequence variation compared
the VL and VH regions of PRO165. In particular embodiments, the CDR
sequences of said functionally active variant are at least 70%,
particularly at least 80%, more particularly at least 90%
homologous to the CDR sequences of the VL and VH regions of PRO165.
Most particularly, the CDR sequences of said functionally active
variant are at least 90% identical and at least 95% homologous to
the CDR sequences of the VL and VH regions of PRO165. In particular
such embodiments, at least the CDR3 regions of the VH regions of
said functional variant are identical to the corresponding CDR3
regions of PRO165. In more particular embodiments, all CDR regions
of said functional variant are identical to the corresponding CDR
regions of PRO165.
[0076] In another aspect, the present invention relates to a
nucleic acid or multiple (i.e. more than one) nucleic acids
encoding the bispecific construct of the present invention. If the
bispecific construct is a single-chain construct, e.g. a
polypeptide or protein, a single nucleic acid codes for the
bispecific construct. However, if the bispecific construct
comprises two or more polypeptides, the bispecific construct of the
present invention may also be encoded by two or more separate
nucleic acids. The nucleic acid molecule(s) according to the
invention can be any nucleic acid molecule, particularly a DNA or
RNA molecule, for example cDNA or mRNA. They can be naturally
occurring molecules or produced through genetic engineering or
chemical synthesis. They may be single-stranded molecules, which
either contain the coding or the non-coding strand, or
double-stranded molecules.
[0077] In a particular embodiment of the present invention, said
nucleic acid or nucleic acids encode the bispecific construct
PRO165 (SEQ ID NO: 7), or a functionally active variant
thereof.
[0078] The nucleic acid(s) of the present invention may be produced
by any suitable method as known to those skilled in the art. The
nucleic acids of the present invention can, for example, be
synthesized by the phosphoramidite method or the like, or can be
produced by polymerase chain reaction (PCR) using specific primers.
Furthermore, methods for introducing a desired mutation into
certain nucleotide sequence, such as site-directed mutagenesis
techniques, are well-known to a person skilled in the art.
[0079] In a further aspect, the present invention relates to a
vector or multiple vectors comprising the nucleic acid(s) of the
present invention. When comprised within a vector, in particular a
plasmid, the nucleic acid(s) particularly is (are) DNA. The types
of vectors used in the present invention are not particularly
limited. For example, the vector may be a vector which replicates
autonomously, such as a plasmid, or may be a vector which is
integrated into the genome of a host cell when introduced into the
host cell and is replicated along with the chromosome.
Particularly, the vector used in the present invention is an
expression vector, in particular an expression plasmid. In an
expression vector, elements necessary for transcription, such as a
promoter, are operatively linked to the DNA nucleic acid(s) of the
present invention.
[0080] Examples of promoters which are operative in bacterial cells
include PR or PL promoters of phage lambda, lac, trp or tac
promoter of Escherichia coli, and the like. Examples of mammalian
promoters include SV40 promoter, MT-1 (metallothionein gene)
promoter, adenovirus 2 major late promoter, and the like.
Furthermore, exemplary promoters for use in insect cells include
polyhedrin promoter, P10 promoter, baculovirus immediate early gene
1 promoter, and the like. Moreover, suitable promoters for yeast
host cells include a promoter derived from yeast glycolysis system
genes, TPI1 promoter and the like. Other promoters suited for
different expression systems are known in the art.
[0081] Further, if necessary, the DNA of the present invention may
be operatively linked to a suitable terminator, such as a human
growth hormone terminator or a TPI1 ADH3 fungal host terminator.
The recombinant vector of the present invention may also have an
element such as a polyadenylation signal (e.g., derived from SV40),
a transcription enhancer sequence (e.g., a SV40 enhancer), or a
translation enhancer sequence (e.g., encoding adenovirus VA
RNA).
[0082] The recombinant vector of the present invention is also
typically provided with a DNA sequence which enables the vector to
replicate inside the host cell, and an example thereof for
mammalian cells is an SV40 origin of replication. Furthermore, the
recombinant vector of the present invention may also contain a
selectable marker. Examples of a selectable marker include, inter
alia, drug resistance genes such as ampicillin, kanamycin,
tetracycline, chloramphenicol, neomycin, and hygromycin. Methods
for connecting the nucleic acid(s) of the present invention with a
promoter and, as desired, other regulatory sequences such as a
terminator and/or a secretion signal sequence, and inserting these
into a suitable vector are known to those skilled in the art.
[0083] In a particular embodiment of the present invention, said
vector or vectors comprise a nucleic acid or nucleic acids, which
encode(s) the bispecific construct PRO165 (SEQ ID NO: 7), or a
functionally active variant thereof.
[0084] In yet another aspect, the present invention relates to a
host cell or multiple host cells that are not identical, comprising
the vector(s) of the present invention. The host cell(s) into which
the recombinant vector of the present invention is (are) introduced
is (are) not particularly limited and include any prokaryotic or
eukaryotic cell which can express the vector of the present
invention. Examples of suitable host cells include bacteria (e.g.,
Bacillus spp., Streptomyces spp., and Escherichia coli), mammalian
cells (e.g., HEK293, HeLa, COS, BHK, CHL, and CHO cells), insect
cells (e.g., baculovirus expression system), yeast cells
(Saccharomyces spp. or Schizosaccharomyces spp., in particular
Saccharomyces cerevisae and Saccharomyces kluyveri), and other
fungal cells (e.g., Aspergillus, Neurospora). Particularly, the
cells are bacterial cells, in particular Escherichia coli
cells.
[0085] A multiple polypeptide chain bispecific construct can be
made in a single host cell expression system wherein the host cell
produces each chain of bispecific construct and assembles the
polypeptide chains into a multimeric structure to form the
bispecific construct, followed by recovery of the bispecific
construct from the host cell. Alternatively, the separate
polypeptide chains of the desired bispecific construct can be made
in separate expression host cells, separately recovered from the
respective host cells, and then mixed in vitro under conditions
permitting the formation of the multi-subunit bispecific constructs
as known in the art.
[0086] Methods for introducing the vector of the present invention
into suitable host cells are known in the art and include the
protoplast method, the competent cell method (for bacterial host
cells), electroporation, the phosphate calcium method, lipofection
(for mammalian cells or for insect cells/baculovirus system),
electroporation, the spheroplast method, and the lithium acetate
method (for yeast and other fungal host cells).
[0087] In yet a further aspect, the present invention relates to a
method for producing the bispecific construct of the present
invention, comprising providing a host cell or host cells of the
present invention, culturing said host cell or said host cells and
collecting the bispecific construct from the cell culture. In the
culturing step, the host cell(s) of the present invention is (are)
cultured in a suitable culture medium under conditions permitting
expression of the bispecific construct of the present invention.
The medium used to culture the cells may be any conventional medium
suitable for growing the host cells, such as minimal or complex
media containing appropriate supplements. Alternatively, the
present invention relates to a method for producing the bispecific
construct of the present invention, comprising providing a nucleic
acid or nucleic acids according to the present invention, or a
vector or vectors according to the present invention, expressing
said nucleic acid or nucleic acids or said vector or vectors,
particularly in an in vitro transcription/translation system (see,
for example, Yin et al., Mabs 2012 Mar. 1; 4(2) 217-25), and
collecting said bispecific construct from the expression
system.
[0088] In the step of collecting the bispecific construct from the
cell culture, the produced bispecific construct is recovered by
conventional methods for isolating and purifying a protein,
including separating the host cells from the medium by
centrifugation or filtration, precipitating the proteinaceous
components of the supernatant or filtrate by means of a salt, e.g.
ammonium sulphate, and purification by a variety of chromatographic
procedures, e.g. ion exchange chromatography, gel filtration
chromatography, affinity chromatography or the like. In a case
where the bispecific complex forms insoluble inclusion bodies, for
example when using E. coli as host cell, the inclusion bodies may
be first solubilized in denaturant, followed by a refolding step in
accordance with procedures well known in the art.
[0089] In still another aspect, the present invention relates to a
pharmaceutical composition comprising the bispecific construct of
the present invention and a pharmaceutically acceptable carrier. As
used herein, the term "pharmaceutically acceptable" refers to those
compounds or substances which are, within the scope of sound
medical judgment, suitable for contact with the tissues of mammals,
especially humans, without excessive toxicity, irritation, allergic
response and other problem complications. The term "carrier", as
used herein, relates to a diluent, adjuvant, excipient or vehicle
whereby the active ingredient is administered. Pharmaceutically
acceptable carriers for use herein can be, for example, sterile
liquids or dispersions. Particular carriers are those suited for
intravenous, subcutaneous or topical administration, including
sterile aqueous and non-aqueous solutions or suspensions for
parenteral administration, as discussed in Remington: The Science
and Practice of Pharmacy, 20th Edition (2000).
[0090] The pharmaceutical composition generally includes an
effective amount of the bispecific construct of the present
invention. Within the present invention, the term "effective
amount" refers to the amount of a compound sufficient to effect
beneficial or desired therapeutic results. A therapeutically
effective amount can be administered in one or more
administrations, applications or dosages and is not intended to be
limited to a particular formulation or administration route. Also,
the pharmaceutical composition may include one or more additional
active substances that are co-administered with the bispecific
construct of the present invention. In addition, the pharmaceutical
composition may contain additional pharmaceutically acceptable
substances, for example pharmaceutical acceptable excipients such
as solubilizing agents, surfactants, tonicity modifiers and the
like.
[0091] Furthermore, the dosage form of the pharmaceutical
composition of the present invention is not particularly limited
but particularly is a parenteral formulation, such as an aqueous or
non-aqueous solution or dispersion for injection or infusion, or a
formulation suited for topical administration. Another particular
dosage form is a formulation containing the bispecific construct of
the present invention formulated in a controlled or sustained or
delayed release matrix. Further, the pharmaceutical composition may
also be contained in an implantable device that releases the
bispecific construct over time.
[0092] In still a further aspect, the present invention relates to
the use of the bispecific construct of the present invention in the
treatment of an inflammatory and/or autoimmune disease. In
particular, the present invention relates to a method for the
treatment of an inflammatory and/or autoimmune disease, comprising
administering to a subject, particularly a human patient, an
effective amount of the bispecific construct of the present
invention. The meaning of the term "effective amount" is as defined
herein above. Typically, an effective amount of the bispecific
construct of the present invention is administered in form of the
above-described pharmaceutical composition. Suitable administration
routes include, but are not limited to, topical and parenteral
administration, in particular inhalation, subcutaneous injection,
intravenous injection, and injection into the cerebrospinal fluid.
The administration regimen is not particularly limited and
includes, for example, bi-weekly, monthly, once every other month,
once every third, sixth or ninth month and once-a-year or single
application administration schemes.
[0093] The inflammatory and/or autoimmune disease may be rheumatoid
arthritis, ankylosing spondylitis, psoriasis, psoriatic arthritis,
ulcerative colitis, Crohn's disease, systemic lupus erythematosus,
juvenile diabetes, autoimmune uveitis, and multiple sclerosis,
Parkinson's disease, Alzheimer's disease, and ischemia-reperfusion
injury.
EXAMPLES
Example 1
Cloning of Bispecific Antibody Construct
[0094] A bispecific construct
V.sub.HA-L1-V.sub.LB-L2-V.sub.HB-L3-V.sub.LA (wherein the V.sub.LA
and V.sub.HA domains jointly form the antigen binding site for
CD3.epsilon., and V.sub.LB and V.sub.HB jointly form the antigen
binding site for IL23R) can be assembled by cloning V.sub.LA and
V.sub.HA from the humanized anti-CD3.epsilon. antibody domain
comprised in antibody bscCDl9.times.CD3 (see EP 1 348 715 A2, FIG.
8, nucleotides 1258-1575, and nucleotides 847-1203, respectively),
and V.sub.LB and V.sub.HB from the humanized anti-IL23R antibody
20D7 (see EP 2 395 025 A1, SEQ ID NOs: 9 and 4, respectively) with
linkers L1 and L3 each consisting of the amino acid sequence GGGGS
(G.sub.45) and the middle linker L2 consisting of the amino acid
sequence GGGGSGGGGSGGGGSGGGGS (G.sub.45).sub.4 into an expression
vector suitable for expression in E. coli, including an N-terminal
signal sequence for secretion of the bispecific construct into the
periplasm of the E. coli host cells T, using the techniques
described in Holliger et al., Proc. Natl. Acad. Sci USA
90:6444-6448 (1993), Kipriyanov et al., J. Mol. Biol. 293:41-56
(1999) and Brusselbach et al., Tumor Targeting 4:115-123
(1999).
Example 2
Expression Level of IL23R on Cancer Cell-Lines
[0095] The data available in the public domain suggest that IL23R
may be upregulated in certain tumors. However, the available
information is not sufficient to validate IL23R as a suitable
marker to target cancer cells by a bispecific
anti-IL23R.times.CD3.epsilon. antibody format, as neither the
absolute expression level, nor the specificity of expression nor
the penetrance of IL23R upregulation across different tumor samples
are known. To further study the suitability of IL23R as a label for
the targeted lysis of tumor cells, we assessed the expression level
of IL23R both, on collection of primary cancer tissues, as well as
on a broad spectrum of tumor cell-lines. Surprisingly, IL23R mRNA
expression levels were elevated in most primary tissue samples from
colorectal cancers. Similarly, elevated IL23R mRNA expression was
found in all 129 CRC cell-lines studied. In agreement with these
findings, IL23R was highly upregulated in all six colorectal cancer
cell-lines studied as well as on the A549 lung adenocarcinoma
cell-line also on a protein level as assessed by flow-cytometry
(FIG. 2 and FIG. 3). Quantification of IL23R copies per cell
revealed an expression level of about 10'000-88'000 copies per CRC
cell (Table 1). Remarkably, we found strong expression of IL23R
protein also on cell-lines that were published to be negative for
the validated tumor markers CEA and EGFR, both targets against
which bispecific T cell redirecting antibody therapeutics are
currently in development (Osada, T. et al.2010. British Journal of
Cancer; 101:124-133; Lutterbuese, R. et al.2010.PNAS;
107:12605-12610). Our data suggest that IL23R is a tumor marker
that is specifically upregulated in most colorectal cancers, and
that a bispecific anti-IL23R.times.CD3.epsilon. antibody for the
targeted lysis of CRC cells has potential also in patients that are
refractory to anti-CEA or anti-EGFR therapies. Interestingly, we
found similar IL23R mRNA expression levels also in a variety of
leukemia and lymphoma cell-lines and confirmed elevated IL23R
protein expression in all cell lines tested (FIG. 4).
TABLE-US-00001 TABLE 1 IL23R molecules expressed on the surface of
cancer cell-lines. sample .DELTA.MFI * S/N * ABC * COLO 678 17476
172.33 88'302 DLD-1 13874 134.40 68'763 HCT 116 1539 9.79 10'553
HT-29 15540 65.21 74'865 LS-174T 8866 51.38 47'011 SW 480 18985
138.57 77'428 A549 1604 15.32 11'864 TF-1 12410 74.43 67'904 697
468 10.64 5'734 KIT225 1694 17.13 15'094 DB 563 3.51 5'677 SU-DHL-4
113 3.4 1'441 .DELTA.MFI, difference in mean fluorescence
intensity, and S/N, Signal to background ratio between anti-IL23R
antibody and isotype control. ABC, antigen binding capacity as
determined by regression to reference standard beads.
Example 3
Identification of Monoclonal Rabbit Antibodies Binding to Human
Interleukin (IL)-23 Receptor
[0096] A total of 475 monoclonal B-cells producing antibodies
specifically binding to interleukin-23 receptor were isolated from
immunized rabbits using flow-cytometry-based single-cell sorting,
the principles of which are well known to the expert and are for
example described by Lalor et al Eur J Immunol.1992;22.3001-2011.
Monoclonal B cell culture supernatants were first subjected to
ELISA screening for binding to human IL23R ECD. In a second step,
cross-reactivity to IL23R from mouse and cynomolgus monkey was
assessed. Further, the affinity to human and cynomolgus IL23R was
assessed using the surface plasmon resonance (SPR) technology
(Table 2). The median equilibrium dissociation constant (KD) of
those 475 monoclonal antibodies to human IL23R was 6.3E-11M. Five
percent of these antibodies bound with an estimated KD below
4.3E-13M. A total of 92 clones selected either for their high
affinity or their cross-reactivity to cynomolgus and/or mouse, were
subjected to PCR amplification and sequencing of their variable
domains.
[0097] The sequencing of the obtained rabbit IgG clones resulted in
68 complete sets of light and heavy chain variable domains (VL and
VH). These sets of rabbit variable domains were analyzed by
sequence alignment to identify unique clones and to group the
sequences into clusters based on sequence homology. This alignment
of the VL and VH domains was performed based on the joint amino
acid sequences of both domains. The analysis led to the
identification of 58 unique clones. In addition to the alignment of
the variable domains, the set of sequences of the six
complementarity determining regions (CDRs) of each rabbit IgG clone
were compared between different clones to identify unique sets of
CDRs. In total 58 unique sets of rabbit CDRs, corresponding to 58
independent clones, were identified. These 58 CDR sets were aligned
using the multiple alignment tool COBALT and a phylogenetic tree
was generated with the Neighbor Joining algorithm as shown in FIG.
5. Twenty three clones from different clusters were selected based
on their affinity for human, cynomolgus and mouse IL23R for
recombinant production and further characterization with the aim to
proceed with high sequence diversity.
Example 4
Heterologous Production of Monoclonal Rabbit Antibodies
[0098] Following the selection of the clones (described above)
rabbit antibodies were expressed and purified for further
characterization. The cloning of the corresponding light and heavy
chain variable domains entailed the in-vitro ligation of the DNA
fragments into a suitable mammalian expression vector. These
expression vectors contained consensus sequences for the constant
domains of the rabbit IgG light and heavy chains to allow for the
assembly and secretion of fully functional rabbit monoclonal IgGs
upon co-expression. Subsequent to the vector construction the
sequence of the resulting constructs was confirmed again and the
plasmid DNA was amplified and purified for mammalian cell
transfections. The expression vectors for the rabbit antibody heavy
and light chains were transfected into a mammalian suspension cell
line for transient heterologous expression by a lipid-based
transfection reagent. The conditions like the ratio of heavy to
light chain vector were optimized for robust expression levels of
secreted monoclonal IgG. The expression culture was cultivated for
7 days in a shaking incubator. At the end of the heterologous
expression period the cell culture supernatant was harvested by
centrifugation and decanting. Subsequently the secreted rabbit IgGs
were affinity purified by Protein A beads. The IgG loaded beads
were washed and the purified antibodies were eluted by a pH shift.
The elution fractions were analyzed by sodium dodecyl sulfate
polyacrylamide gel electrophoresis (SDS-PAGE), UV absorbance at 280
nm and size-exclusion high performance liquid chromatography
(SE-HPLC) to verify identity, content and purity.
Example 5
Characterization of Purified Monoclonal Rabbit Anti-IL23R
Antibodies
[0099] The affinity of the 23 purified rabbit monoclonal antibodies
towards IL23R from human, cynomolgus monkey and mouse origin was
determined by SPR measurements. The respective results are given in
Table 2 below:
TABLE-US-00002 TABLE 2 Human IL23R Cyno IL23R Mouse IL23R Clone ID
k.sub.a k.sub.d K.sub.D k.sub.a k.sub.d K.sub.D k.sub.a k.sub.d
K.sub.D IgG [M.sup.-1 s.sup.-1] [s.sup.-1] [M] [M.sup.-1 s.sup.-1]
[s.sup.-1] [M] [M.sup.-1 s.sup.-1] [s.sup.-1] [M] 12-01-A08 NB NB
NB ND ND ND NB NB NB 12-01-F09 1.80E+05 9.12E-05 5.07E-10 1.23E+05
5.37E-03 4.38E-08 NB NB NB 12-02-E05 2.15E+05 <1.0E-06
<4.66E-12 1.03E+05 1.93E-04 1.89E-09 NB NB NB 12-04-H09 1.74E+05
7.59E-05 4.37E-10 4.63E+05 7.71E-03 1.66E-08 NB NB NB 12-06-A05
1.53E+05 1.10E-05 7.17E-11 1.88E+04 8.23E-05 4.39E-09 5.48E+04
4.23E-05 7.72E-10 12-06-E01 1.18E+05 5.66E-05 4.82E-10 7.99E+04
1.14E-03 1.43E-08 1.80E+05 3.64E-03 2.02E-08 12-06-E03 6.58E+04
2.32E-05 3.53E-10 9.57E+04 7.31E-05 7.64E-10 8.91E+04 1.20E-03
1.35E-08 12-06-F06 2.83E+05 1.61E-05 5.70E-11 1.98E+05 5.98E-03
3.02E-08 2.67E+05 2.48E-03 9.31E-09 12-08-E06 9.72E+04 5.44E-05
5.60E-10 6.00E+04 2.49E-05 4.15E-10 NB NB NB 12-09-F05 1.33E+05
4.00E-06 3.00E-11 1.30E+05 4.54E-05 3.49E-10 8.46E+04 1.42E-03
1.68E-08 12-10-A06 NB NB NB ND ND ND NB NB NB 12-19-F08 2.29E+05
2.50E-05 1.10E-10 2.22E+05 1.33E-04 6.00E-10 2.45E+05 3.34E-04
1.36E-09 13-05-H06 NB NB NB NB NB NB NB NB NB 13-10-A03 NB NB NB NB
NB NB NB NB NB 14-03-B01 2.79E+05 .sup. <1E-06 <3.58E-12
3.31E+05 4.82E-05 1.46E-10 NB NB NB 14-05-A11 2.26E+05 .sup.
<1E-06 <4.43E-12 2.52E+05 8.46E-05 3.36E-10 NB NB NB
14-06-H08 3.34E+05 9.92E-06 2.97E-11 4.58E+05 3.17E-06 6.92E-12 NB
NB NB 14-07-H07 2.50E+05 1.59E-05 6.33E-11 2.70E+05 3.00E-05
1.11E-10 NB NB NB 14-08-E05 2.17E+05 5.98E-05 2.76E-10 2.45E+05
3.79E-05 1.55E-10 NB NB NB 14-11-D07 4.14E+05 1.98E-07 4.78E-13
4.48E+05 <1E-06 <2.23E-12 2.23E+05 3.34E-04 1.50E-09
14-13-D08 2.06E+05 .sup. <1E-06 <4.85E-12 3.07E+05 2.77E-05
9.02E-11 NB NB NB 14-14-E08 5.19E+05 .sup. <1E-06 <1.93E-12
5.12E+05 1.58E-05 3.08E-11 NB NB NB 14-17-B09 6.77E+05 7.49E-05
1.11E-10 3.53E+05 1.16E-04 3.30E-10 8.08E+04 <1E-06
<1.24E-11
Example 6
Engineering and Characterization of a Humanized Single-Chain Fv
Fragment
[0100] The humanization of rabbit antibody clone 14-11-D07
comprised the transfer of the rabbit CDRs onto Numab's proprietary
scFv acceptor framework of the V.kappa.1/VH3 type. In this process
the amino acid sequence of the six CDR regions was identified on
the rabbit antibody donor sequence as described elsewhere (Borras,
L. et al. 2010. JBC; 285:9054-9066) and grafted into the Numab
acceptor scaffold sequence. Two variants were generated, where the
variant sc01 resulted from exclusively engrafting complementarity
determining regions (CDRs) onto the human acceptor variable domain
scaffold, while variant sc02 contains further mutations also in the
human framework sequence. The two resulting humanized scFvs were
characterized for their binding affinity towards IL23R from human,
cynomolgus and mouse origin (see Table 3). As no significant
difference in affinity was detectable for the two variants,
14-11-D07-sc01 was chosen to be engineered in the scDb format
because in this variant no rabbit amino acids were engrafted from
the rabbit donor framework sequences to the human acceptor
sequence, thus minimizing the risk to provoke anti-drug immune
response in humans following application.
TABLE-US-00003 TABLE 3 human IL23R cyno IL23R mouse IL23R Clone ID
k.sub.a k.sub.d K.sub.D k.sub.a k.sub.d K.sub.D k.sub.a k.sub.d
K.sub.D scFv [M.sup.-1 s.sup.-1] [s.sup.-1] [M] [M.sup.-1 s.sup.-1]
[s.sup.-1] [M] [M.sup.-1 s.sup.-1] [s.sup.-1] [M] 14-11-D07-sc01
2.24E+06 2.59E-04 1.16E-10 2.92E+06 3.61E-04 1.24E-10 1.89E+06
4.18E-03 2.21E-09 14-11-D07-sc02 1.17E+06 1.13E-04 9.60E-11
1.55E+06 2.05E-04 1.33E-10 8.30E+05 1.39E-03 1.68E-09
Example 7
Engineering and Characterization of a Bispecific Single-Chain
Diabodies (scDb)
[0101] With the aim to redirect CD3.epsilon.+ T cells to lyse IL23R
expressing target cells, a bispecific antibody fragment of the
so-called single-chain diabody (scDb) format was engineered. This
construct termed PRO165 contains the VH and VL of the anti-IL23R
scFv 14-11-D07-sc01, as well as the VH and VL of a humanized rabbit
anti-CD3.epsilon. antibody (clone 6). The anti-CD3.epsilon. binding
domain was selected a) for its high affinity to human CD3.epsilon.,
b) for its excellent cross-reactivity to CD3.epsilon. from
cynomolgus origin, c) for its outstanding stability and resistance
towards aggregation, and d) because this CD3.epsilon. binder
activates T cells exclusively upon cross-linking--as it may for
example occur following binding to target cells--thereby minimizing
the risk for potential side-effects due to unspecific activation of
T cells.
[0102] Affinities of the anti-IL23R and anti-CD3.epsilon. binding
moieties towards human, cyno and mouse IL23R, and human and mouse
CD3.epsilon., respectively were measured by SPR (Table 4).
TABLE-US-00004 TABLE 4 human IL23R human CD3.epsilon. k.sub.d
K.sub.D K.sub.D k.sub.a k.sub.d K.sub.D scDb ID [s.sup.-1] [M] [M]
[M.sup.-1 s.sup.-1] [s.sup.-1] [M] PRO165 1.26E-03 1.16E-08
1.82E-10 1.09E+05 1.26E-03 1.16E-08
[0103] The midpoint of transition for the thermal unfolding of the
tested constructs was determined by Differential Scanning
Fluorimetry (DSF), essentially as described by Niesen (Niesen et
al., Nat Protoc. 2 (2007) 2212-21). The DSF assay is performed in a
qPCR machine (e.g. MX3005p, Agilent Technologies). The samples were
diluted in buffer (citrate-phosphate pH 6.4, 0.25 M NaCl)
containing a final concentration of 5.times. SYPRO orange in a
total volume of 25 .mu.L. Samples were measured in duplicate and a
temperature ramp from 25-96.degree. C. programmed. The fluorescence
signal was acquired and the raw data was analyzed with the GraphPad
Prism (GraphPad Software Inc.; results see Table 5).
TABLE-US-00005 TABLE 5 The midpoint of transition for the thermal
unfolding was determined for all constructs by differential
scanning fluorimetry Thermal Unfolding scDb ID anti-IL23R anti-CD3
Tm PRO165 14-11-D07-sc01 clone 6 65.3
Example 8
Targeted Lysis of IL23R Expressing Cells
[0104] To study potency of the scDbs to induce specific lysis of
target cells, IL23R expressing cells were co-cultivated with human
CD8+ T cells in presence of increasing concentrations of the
respective scDb. Lysis of cells in dependence of the scDb
concentration was assessed by measuring fluorescence intensity of
celltox-green intercalated into DNA. The EC50 of PRO165 for the
respective cell-line is given in Table 6.
TABLE-US-00006 TABLE 6 IL23R binding EC.sub.50 of specific target
cell lysis [nM] ID Format moiety DLD-1 SW-480 TF-1 CHO PRO165 scDb
14-11-D07-sc01 45.4 71.7 39.8 no lysis
Methods:
1. Assessment of IL23R Expression Levels on Cell Lines
[0105] For the detection of IL23R on the cell membrane, living
cells were stained with 5 .mu.g/mL of a biotinylated polyclonal
goat anti-IL23R antibody (R&D Systems, Cat. No. BAF1400). As
background control, a polyclonal goat IgG isotype was used (R&D
Systems, Cat. No. BAF108). Binding of goat polyclonal antibodies to
cells was in turn detected by a Phycoerythrin-(PE)-labeled
streptavidin (Southern Biotech, Cat. No. 7100-09S). PE fluorescence
intensity of stained cells was measured by flow-cytometry (FACS
aria III, Becton Dickinson). In order to quantify IL23R molecules
per cell anti-human IgG Quantum.TM. Simply Cellular.RTM. (QSC)
microspheres (Bangs Laboratories, Cat. No. 816) loaded with human
IL-23R Fc chimera (R&D Systems, Cat. No.1400-IR-050) were used
as a reference standard. The mean fluorescence intensity (MFI),
reflecting the signal intensity at the geometric mean, was measured
for both, the goat IgG isotype control as well as for the goat
anti-IL23 R antibody. The difference between the MFI of the
specific antibody and isotype control antibody (.DELTA.MFI) was
calculated. The normalized MFI was calculated by dividing the MFI
obtained with the anti-IL23R antibody by the MFI of the idiotype
control. To quantify IL23R molecules on the cell surface the
specific Antibody Binding Capacity (ABC) of cells was calculated by
regression of the respective MFI to the standard curve generated by
use of Quantum.TM. Simply Cellular.RTM. (QSC) microspheres.
Calculations were performed in the lot-specific QuickCal.RTM.
template. To compare unspecific binding the ABC value of cells
stained with negative control antibody were subtracted from ABC
value of cells stained with the specific antibody.
2. SPR Assay for Determination of Binding Kinetics and Species
Cross-Reactivity of Monoclonal Antibodies in Culture
Supernatant
[0106] Binding affinities of monoclonal rabbit anti-IL23R
antibodies in sort supernatants were measured by surface plasmon
resonance (SPR) using a MASS-1 SPR instrument (Sierra Sensors). For
affinity measurements (run in DPBS with 0.05% Tween) an antibody
specific for the Fc region of rabbit IgGs (Bethyl Laboratories,
Cat. No. A120-111A) was immobilized on a sensor chip (SPR-2
Affinity Sensor, Amine, Sierra Sensors) using a standard
amine-coupling procedure. After immobilization, rabbit monoclonal
antibodies in culture supernatants were captured by the anti-rabbit
IgG antibody while a second immobilized channel served as a control
where the capture was replaced by negative supernatant (cultured
media that does not contain sorted cells). Human IL23R
extracellular domain (ECD) (produced on request by Trenzyme,
Germany) at 90 nM was injected into both flow cells for 3 min and
dissociation of the protein from the captured IgG on the sensor
chip was allowed to proceed for 5 min. In a similar manner the
affinities for cynomolgus and mouse IL23R ECD (both at 90 nM,
produced on request by Trenzyme) were measured. The apparent
dissociation (kd) and association (ka) rate constants and the
apparent dissociation equilibrium constant (KD) were calculated
with the MASS-1 analysis software (Analyzer, Sierra Sensors) using
one-to-one Langmuir binding model.
3. SPR Assay for Determination of Binding Kinetics and Species
Cross-Reactivity of Purified Monoclonal Antibodies
[0107] Binding affinities of purified monoclonal rabbit anti-IL23R
antibodies were measured in a similar setup as the sort
supernatants, except that the sort supernatants were replaced by
purified IgGs. A sensor chip (SPR-2 Affinity Sensor, High Capacity
Amine, Sierra Sensors) was immobilized by the same procedure, and
purified monoclonal antibodies at a concentration of 0.5 .mu.g/ml
(diluted in HEPES running buffer: 0.01 M HEPES, 0.15 M NaCl, 0.05%
Tween) were captured by the anti-rabbit IgG antibody. No capture
was done on the immobilized control channel. Two-fold serial
dilutions of human IL23R extracellular domain ranging from 90 to
2.81 nM were injected into the flow cells for 3 min and
dissociation of the protein from the captured IgG on the sensor
chip was allowed to proceed for 5 min. After each injection cycle,
surfaces were regenerated with a single 1 min injection of 10 mM
glycine-HCl pH 1.5. In a similar manner the affinities for
cynomolgus and mouse IL23R ECD were measured. The apparent
dissociation (kd) and association (ka) rate constants and the
apparent dissociation equilibrium constant (KD) were calculated
with the MASS-1 analysis software (Analyzer, Sierra Sensors) using
one-to-one Langmuir binding model.
4. SPR Assay for Determination of Binding Kinetics and Species
Cross-Reactivity of Anti-IL23R scFvs
[0108] Binding affinities of anti-IL23R scFvs were measured by
surface plasmon resonance (SPR) using a MASS-1 SPR instrument
(Sierra Sensors). For affinity measurements (done in HEPES running
buffer: 0.01 M HEPES, 0.15 M NaCl, 0.05% Tween) an antibody
specific for the Fc region of human IgGs (Bethyl Laboratories, Cat.
No. A80-104A) was immobilized on a sensor chip (SPR-2 Affinity
Sensor, High Capacity Amine, Sierra Sensors) using a standard
amine-coupling procedure. After immobilization, 1 ug/ml recombinant
human IL23R Fc chimera (R&D Systems, Cat. No. 1400-IR-050) was
captured by the anti-human IgG antibody while a second immobilized
channel served as a control where the capture was replaced by
buffer. Two-fold serial dilutions of human scFvs ranging from 180
to 2.81 nM were injected into both flow cells for 3 min and
dissociation of the scFvs from the chimera on the sensor chip was
allowed to proceed for 700 sec. After each injection cycle,
surfaces were regenerated with two 1 min injections of 10 mM
glycine-HCl pH 1.5. In a similar manner the affinities for
cynomolgus and mouse IL23R Fc chimera (R&D Systems, Cat. No.
1686-MR-050) was measured. The apparent dissociation (kd) and
association (ka) rate constants and the apparent dissociation
equilibrium constant (KD) were calculated with the MASS-1 analysis
software (Analyzer, Sierra Sensors) using one-to-one Langmuir
binding model.
5. SPR Assay for Determination of Binding Kinetics and Species
Cross-Reactivity of Anti-CD3.times.IL23R scDbs
[0109] Binding affinities of anti-CD3.times.IL23R scDbs were
measured by surface plasmon resonance (SPR) using a MASS-1 SPR
instrument (Sierra Sensors). For affinity measurements (done in
HEPES running buffer: 0.01 M HEPES, 0.15 M NaCl, 0.05% Tween) to
CD3, human heterodimeric single-chain CD3.gamma..delta.
extracellular domain (produced in-house) was immobilized on a
sensor chip (SPR-2 Affinity Sensor High Capacity Amine, Sierra
Sensors) using a standard amine-coupling procedure. Three-fold
serial dilutions of scDbs ranging from 90 to 0.123 nM were injected
into the flow cells for 3 min and dissociation of the protein from
the immobilized CD3.gamma..delta. on the sensor chip was allowed to
proceed for 700 sec. After each injection cycle, surfaces were
regenerated with a 1 min injection of 10 mM Glycine-HCl pH 2.0. In
a similar manner the binding to cynomolgus CD3.gamma..delta.
(produced in-house) and mouse CD3.delta..gamma. (Sino Biologicals
Inc., Cat. No. CT033-M2508H) was measured.
[0110] For affinity measurements to IL23R, human IL23R
extracellular domain (produced on request by Trenzyme) was
immobilized on a sensor chip (SPR-2 Affinity Sensor High Capacity
Amine, Sierra Sensors) using a standard amine-coupling procedure.
Two-fold serial dilutions of scDbs ranging from 90 to 5.6 nM were
injected into the flow cells for 3 min and dissociation of the
protein from the immobilized IL23R on the sensor chip was allowed
to proceed for 720 sec. After each injection cycle, surfaces were
regenerated with a 1 min injection of 10 mM Glycine-HCl pH 2.0. The
apparent dissociation (kd) and association (ka) rate constants and
the apparent dissociation equilibrium constant (KD) are calculated
with the MASS-1 analysis software (Analyzer, Sierra Sensors) using
one-to-one Langmuir binding model.
6. scDb Mediated Lysis of IL-23R Expressing Cells by Cytotoxic T
Cells
[0111] For the assessment of the potential of bispecific
anti-CD3.times.IL-23R scDbs to induce target cell lysis human
IL-23R expressing cell lines were used. Colon carcinoma DLD-1 or
SW480, and erythroleukemia TF-1 were used as target cell lines
Unstimulated human CD8+ T-cells isolated as described above were
used as effector cells. Target cells were labeled with cell tox
green dye (Promega) according to the manufacturer's instructions.
Cell lysis was monitored by the CellTox.TM. green cytotoxicity
assay (Promega). The assay measures changes in membrane integrity
that occur as a result of cell death. The assay uses an asymmetric
cyanine dye that is excluded from viable cells but preferentially
stains the dead cell DNA. When the dye binds DNA in compromised
cells, its fluorescence properties are substantially enhanced.
Viable cells produce no appreciable increases in fluorescence.
Therefore, the fluorescence signal produced by the binding
interaction with dead cell DNA is proportional to cytotoxicity.
Similarly as described above, labeled IL-23R cells (5'000
cells/well) were incubated with CD8+ cytotoxic T-cells at an
effector:target ratio of 40:1 in presence of 3-fold serially
diluted scDbs (starting concentration 180 nM) in 96 well microtiter
plates. To assess unspecific lysis of cells that do not express the
target, T-cells were co-incubated with labeled wild-type CHO cells.
Fluorescence intensity was analyzed after 48 h of incubation using
a multi-mode microplate reader (FlexStation 3, Molecular Devices).
Data were analyzed using a four-parameter logistic curve fit using
the SoftMax.quadrature. Pro data analysis Software (Molecular
Devices), and the molar concentration of scDb required to induce
half maximal target cell lysis (EC.sub.50) was derived from
dose-response curves.
[0112] In order to specifically track the fate of target cells,
target cells were stained with CellVue.RTM. Claret Far Red
Fluorescent (Sigma-Aldrich, Cat. No. MINCLARET-1KT) in a
concentration of 5 nM Dye according to the manufacturer's
instructions. Apoptosis/necrosis was monitored using the Annexin V
Apoptosis Detection Kit FITC (eBioscience, Cat. No. 88-8005-74)
according to the manufacturer's instructions (concentration of
dyes: 100 .mu.L/mL Annexin V and 2 .mu.g/mL Propidium iodide).
Stained IL-23R cells (5'000 cells/well) were incubated with CD8+
cytotoxic T-cells at an effector:target ratio of 40:1 in presence
of serially diluted scDbs (starting concentration 180 nM) in 96
well microtiter plates. To assess unspecific lysis of cells that do
not express the target, T-cells were co-incubated with labeled CHO
cells. Fluorescence intensities were analyzed after 48 h of
incubation using a flow cytometer (FACS aria III, Becton
Dickinson). Data were analyzed by discriminate target from effector
cells using the far red fluorescent dye (CellVue.RTM. Claret Far
Red Fluorescent). Target cells were gated into live cells and
early-/late-stage apoptotic, necrotic cells by Annexin V and PI
fluorescence. The data obtained were analyzed using a
four-parameter logistic curve fit using the SoftMax.RTM. Pro data
analysis Software (Molecular Devices), and the molar concentration
of scDb required to induce half maximal target cell lysis (EC50)
was derived from dose-response curves.
7. Construct Design and Manufacturing of scDb Constructs
[0113] The single-chain diabody constructs were designed by
arranging the variable domains in a VLA-L1-VHB-L2-VLB-L3-VHA
configuration. In these constructs the VLA and VHA domains jointly
form the binding site for IL23R while the VLB and VHB domains
jointly form the binding site for CD3.epsilon.. The peptide linkers
L1-L3 connecting the variable domains are constructed of the
glycine/serine repeats. The two short linkers L1 and L3 are
composed of a single G4S repeat, whereas the long linker L2 is
composed of the sequence (G4S)4. The nucleotide sequences encoding
the various anti-IL23R.times.CDE3.epsilon. scDb constructs were de
novo synthesized and cloned into an adapted vector for E. coli
expression that is based on a pET26b(+) backbone (Novagen).
[0114] The expression construct was transformed into the E. coli
strain BL12 (DE3) (Novagen) and the cells were cultivated in 2YT
medium (Sambrook, J., et al., Molecular Cloning: A Laboratory
Manual) as a starting culture. Expression cultures were inoculated
and incubated in shake flasks at 37.degree. C. and 200 rpm. Once an
OD600 nm of 1 was reached protein expression was induced by the
addition of IPTG at a final concentration of 0.5 mM. After
overnight expression the cells were harvested by centrifugation at
4000 g. For the preparation of inclusion bodies the cell pellet was
resuspended in IB Resuspension Buffer (50 mM Tris-HCl pH 7.5, 100
mM NaCl, 5 mM EDTA, 0.5% Triton X-100). The cell slurry was
supplemented with 1 mM DTT, 0.1 mg/mL Lysozyme, 10 mM Leupeptin,
100 .mu.M PMSF and 1 .mu.M Pepstatin. Cells were lysed by 3 cycles
of ultrasonic homogenization while being cooled on ice.
Subsequently 0.01 mg/mL DNAse was added and the homogenate was
incubated at room temperature for 20 min. The inclusion bodies were
sedimented by centrifugation at 15000 g and 4.degree. C. The IBs
were resuspended in IB resuspension Buffer and homogenized by
sonication before another centrifugation. In total a minimum of 3
washing steps with IB Resuspension Buffer were performed and
subsequently 2 washes with IB Wash Buffer (50 mM Tris-HCl pH 7.5,
100 mM NaCl, 5 mM EDTA) were performed to yield the final IBs.
[0115] For protein refolding the isolated IBs were resuspended in
Solubilization Buffer (100 mM Tris/HCl pH 8.0, 6 M Gdn-HCl, 2 mM
EDTA) in a ratio of 5 mL per g of wet IBs. The solubilization
mixture was incubated for 30 min at room temperature until DTT was
added at a final concentration of 20 mM and the incubation was
continued for another 30 min. After the solubilization was
completed the solution was cleared by 10 min centrifugation at
21500 g and 4.degree. C. The refolding was performed by rapid
dilution at a final protein concentration of 0.3 g/L of the
solubilized protein in Refolding Buffer (typically: 100 mM Tris-HCl
pH 8.0, 5.0 M Urea, 5 mM Cysteine,1 mM Cystine). The refolding
reaction was routinely incubated for a minimum of 14 h. The
resulting protein solution was cleared by 10 min centrifugation at
8500 g and 4.degree. C. The refolded protein was purified by
affinity chromatography on Capto L resin (GE Healthcare) followed
by a size-exclusion chromatography on a Superdex 75 column (GE
Healthcare). The proteins were formulated in native buffer (50 mM
Citrate-Phosphate pH 6.4, 150 mM NaCl). The isolated monomer
fraction was analyzed by size-exclusion HPLC, SDS-PAGE for purity
and UV/Vis spectroscopy for protein content.
TABLE-US-00007 Sequence listing for PRO165: VLA-L1-VHB-L2-VLB-
L3-VHA SEQ ID Type Sequence 1 Linker L1 GGGGS 2 Linker L2 GGGGS
GGGGS GGGGS GGGGS Linker L3 GGGGS 3 VL
DIQMTQSPSSLSASVGDRVTITCQASENIYSFLA anti-IL23R
WYQQKPGKAPKLLIYSASKLAAGVPSRFSGSGS 14-11-D07-
GTDFTLTISSLQPEDFATYYCQQTNRYSNPDIYN sc01 VFGQGTKLTVLG 4 VH
EVQLVESGGGLVQPGGSLRLSCAASGIDFNSNY anti-IL23R
YMCWVRQAPGKGLEWIGCIYVGSHVNTYYANW 14-11-D07-
AKGRFTISRDNSKNTVYLQMNSLRAEDTAVYYC sc01 ATSGSSVLYFKFWGQGTLVTVSS 5 VL
DIQMTQSPSSLSASVGDRVTITCQSSESVYNNKR anti-CD3
LSWYQQKPGKAPKLLIYTASSLASGVPSRFSGS clone 6
GSGTDFTLTISSLQPEDFATYYCQGEFTCSNADC FTFGQGTKLTVLG 6 VH
EVQLVESGGGLVQPGGSLRLSCAASGFPLSSYA anti-CD3
MIWVRQAPGKGLEWIGMILRAGNIYYASWVKGR clone 6
FTISRDNSKNTVYLQMNSLRAEDTAVYYCARRH YNREGYPIGIGDLWGQGTLVTVSS 7 PRO165
DIQMTQSPSSLSASVGDRVTITCQASENIYSFLA
WYQQKPGKAPKLLIYSASKLAAGVPSRFSGSGS
GTDFTLTISSLQPEDFATYYCQQTNRYSNPDIYN VFGQGTKLTVLGGGGGSEVQLVESGGGLVQPG
GSLRLSCAASGFPLSSYAMIWVRQAPGKGLEWI
GMILRAGNIYYASWVKGRFTISRDNSKNTVYLQM
NSLRAEDTAVYYCARRHYNREGYPIGIGDLWGQ GTLVTVSSGGGGSGGGGSGGGGSGGGGSDIQ
MTQSPSSLSASVGDRVTITCQSSESVYNNKRLS WYQQKPGKAPKLLIYTASSLASGVPSRFSGSGS
GTDFTLTISSLQPEDFATYYCQGEFTCSNADCFT FGQGTKLTVLGGGGGSEVQLVESGGGLVQPGG
SLRLSCAASGIDFNSNYYMCWVRQAPGKGLEWI
GCIYVGSHVNTYYANWAKGRFTISRDNSKNTVYL
QMNSLRAEDTAVYYCATSGSSVLYFKFWGQGTL VTVSS
Sequence CWU 1
1
715PRTArtificial Sequencesynthetic peptide linker 1Gly Gly Gly Gly
Ser 1 5 220PRTArtificial Sequencesnythetic peptide linker 2Gly Gly
Gly Gly Ser Gly Gly Gly Gly Ser Gly Gly Gly Gly Ser Gly 1 5 10 15
Gly Gly Gly Ser 20 3113PRTArtificial SequenceVL anti-IL23R
14-11-D07-sc01 3Asp Ile Gln Met Thr Gln Ser Pro Ser Ser Leu Ser Ala
Ser Val Gly 1 5 10 15 Asp Arg Val Thr Ile Thr Cys Gln Ala Ser Glu
Asn Ile Tyr Ser Phe 20 25 30 Leu Ala Trp Tyr Gln Gln Lys Pro Gly
Lys Ala Pro Lys Leu Leu Ile 35 40 45 Tyr Ser Ala Ser Lys Leu Ala
Ala Gly Val Pro Ser Arg Phe Ser Gly 50 55 60 Ser Gly Ser Gly Thr
Asp Phe Thr Leu Thr Ile Ser Ser Leu Gln Pro 65 70 75 80 Glu Asp Phe
Ala Thr Tyr Tyr Cys Gln Gln Thr Asn Arg Tyr Ser Asn 85 90 95 Pro
Asp Ile Tyr Asn Val Phe Gly Gln Gly Thr Lys Leu Thr Val Leu 100 105
110 Gly 4121PRTArtificial SequenceVH anti-IL23R 14-11-D07-sc01 4Glu
Val Gln Leu Val Glu Ser Gly Gly Gly Leu Val Gln Pro Gly Gly 1 5 10
15 Ser Leu Arg Leu Ser Cys Ala Ala Ser Gly Ile Asp Phe Asn Ser Asn
20 25 30 Tyr Tyr Met Cys Trp Val Arg Gln Ala Pro Gly Lys Gly Leu
Glu Trp 35 40 45 Ile Gly Cys Ile Tyr Val Gly Ser His Val Asn Thr
Tyr Tyr Ala Asn 50 55 60 Trp Ala Lys Gly Arg Phe Thr Ile Ser Arg
Asp Asn Ser Lys Asn Thr 65 70 75 80 Val Tyr Leu Gln Met Asn Ser Leu
Arg Ala Glu Asp Thr Ala Val Tyr 85 90 95 Tyr Cys Ala Thr Ser Gly
Ser Ser Val Leu Tyr Phe Lys Phe Trp Gly 100 105 110 Gln Gly Thr Leu
Val Thr Val Ser Ser 115 120 5114PRTArtificial SequenceVL anti-CD3
clone 6 5Asp Ile Gln Met Thr Gln Ser Pro Ser Ser Leu Ser Ala Ser
Val Gly 1 5 10 15 Asp Arg Val Thr Ile Thr Cys Gln Ser Ser Glu Ser
Val Tyr Asn Asn 20 25 30 Lys Arg Leu Ser Trp Tyr Gln Gln Lys Pro
Gly Lys Ala Pro Lys Leu 35 40 45 Leu Ile Tyr Thr Ala Ser Ser Leu
Ala Ser Gly Val Pro Ser Arg Phe 50 55 60 Ser Gly Ser Gly Ser Gly
Thr Asp Phe Thr Leu Thr Ile Ser Ser Leu 65 70 75 80 Gln Pro Glu Asp
Phe Ala Thr Tyr Tyr Cys Gln Gly Glu Phe Thr Cys 85 90 95 Ser Asn
Ala Asp Cys Phe Thr Phe Gly Gln Gly Thr Lys Leu Thr Val 100 105 110
Leu Gly 6123PRTArtificial SequenceVH anti-CD3 clone 6 6Glu Val Gln
Leu Val Glu Ser Gly Gly Gly Leu Val Gln Pro Gly Gly 1 5 10 15 Ser
Leu Arg Leu Ser Cys Ala Ala Ser Gly Phe Pro Leu Ser Ser Tyr 20 25
30 Ala Met Ile Trp Val Arg Gln Ala Pro Gly Lys Gly Leu Glu Trp Ile
35 40 45 Gly Met Ile Leu Arg Ala Gly Asn Ile Tyr Tyr Ala Ser Trp
Val Lys 50 55 60 Gly Arg Phe Thr Ile Ser Arg Asp Asn Ser Lys Asn
Thr Val Tyr Leu 65 70 75 80 Gln Met Asn Ser Leu Arg Ala Glu Asp Thr
Ala Val Tyr Tyr Cys Ala 85 90 95 Arg Arg His Tyr Asn Arg Glu Gly
Tyr Pro Ile Gly Ile Gly Asp Leu 100 105 110 Trp Gly Gln Gly Thr Leu
Val Thr Val Ser Ser 115 120 7501PRTArtificial Sequencerecombinant
anti-CD3/anti-IL23R single-chain diabody (scDb) 7Asp Ile Gln Met
Thr Gln Ser Pro Ser Ser Leu Ser Ala Ser Val Gly 1 5 10 15 Asp Arg
Val Thr Ile Thr Cys Gln Ala Ser Glu Asn Ile Tyr Ser Phe 20 25 30
Leu Ala Trp Tyr Gln Gln Lys Pro Gly Lys Ala Pro Lys Leu Leu Ile 35
40 45 Tyr Ser Ala Ser Lys Leu Ala Ala Gly Val Pro Ser Arg Phe Ser
Gly 50 55 60 Ser Gly Ser Gly Thr Asp Phe Thr Leu Thr Ile Ser Ser
Leu Gln Pro 65 70 75 80 Glu Asp Phe Ala Thr Tyr Tyr Cys Gln Gln Thr
Asn Arg Tyr Ser Asn 85 90 95 Pro Asp Ile Tyr Asn Val Phe Gly Gln
Gly Thr Lys Leu Thr Val Leu 100 105 110 Gly Gly Gly Gly Gly Ser Glu
Val Gln Leu Val Glu Ser Gly Gly Gly 115 120 125 Leu Val Gln Pro Gly
Gly Ser Leu Arg Leu Ser Cys Ala Ala Ser Gly 130 135 140 Phe Pro Leu
Ser Ser Tyr Ala Met Ile Trp Val Arg Gln Ala Pro Gly 145 150 155 160
Lys Gly Leu Glu Trp Ile Gly Met Ile Leu Arg Ala Gly Asn Ile Tyr 165
170 175 Tyr Ala Ser Trp Val Lys Gly Arg Phe Thr Ile Ser Arg Asp Asn
Ser 180 185 190 Lys Asn Thr Val Tyr Leu Gln Met Asn Ser Leu Arg Ala
Glu Asp Thr 195 200 205 Ala Val Tyr Tyr Cys Ala Arg Arg His Tyr Asn
Arg Glu Gly Tyr Pro 210 215 220 Ile Gly Ile Gly Asp Leu Trp Gly Gln
Gly Thr Leu Val Thr Val Ser 225 230 235 240 Ser Gly Gly Gly Gly Ser
Gly Gly Gly Gly Ser Gly Gly Gly Gly Ser 245 250 255 Gly Gly Gly Gly
Ser Asp Ile Gln Met Thr Gln Ser Pro Ser Ser Leu 260 265 270 Ser Ala
Ser Val Gly Asp Arg Val Thr Ile Thr Cys Gln Ser Ser Glu 275 280 285
Ser Val Tyr Asn Asn Lys Arg Leu Ser Trp Tyr Gln Gln Lys Pro Gly 290
295 300 Lys Ala Pro Lys Leu Leu Ile Tyr Thr Ala Ser Ser Leu Ala Ser
Gly 305 310 315 320 Val Pro Ser Arg Phe Ser Gly Ser Gly Ser Gly Thr
Asp Phe Thr Leu 325 330 335 Thr Ile Ser Ser Leu Gln Pro Glu Asp Phe
Ala Thr Tyr Tyr Cys Gln 340 345 350 Gly Glu Phe Thr Cys Ser Asn Ala
Asp Cys Phe Thr Phe Gly Gln Gly 355 360 365 Thr Lys Leu Thr Val Leu
Gly Gly Gly Gly Gly Ser Glu Val Gln Leu 370 375 380 Val Glu Ser Gly
Gly Gly Leu Val Gln Pro Gly Gly Ser Leu Arg Leu 385 390 395 400 Ser
Cys Ala Ala Ser Gly Ile Asp Phe Asn Ser Asn Tyr Tyr Met Cys 405 410
415 Trp Val Arg Gln Ala Pro Gly Lys Gly Leu Glu Trp Ile Gly Cys Ile
420 425 430 Tyr Val Gly Ser His Val Asn Thr Tyr Tyr Ala Asn Trp Ala
Lys Gly 435 440 445 Arg Phe Thr Ile Ser Arg Asp Asn Ser Lys Asn Thr
Val Tyr Leu Gln 450 455 460 Met Asn Ser Leu Arg Ala Glu Asp Thr Ala
Val Tyr Tyr Cys Ala Thr 465 470 475 480 Ser Gly Ser Ser Val Leu Tyr
Phe Lys Phe Trp Gly Gln Gly Thr Leu 485 490 495 Val Thr Val Ser Ser
500
* * * * *