U.S. patent application number 11/893989 was filed with the patent office on 2008-12-18 for antibodies against pd-1 and uses therefor.
Invention is credited to John Andrews, Frances K. Bennett, Beatriz M. Carreno, Laura L. Carter, Mary Collins, Jason Jussif, Deborah Luxenberg, Caroline Russell, Viia Valge-Archer, Clive R. Wood.
Application Number | 20080311117 11/893989 |
Document ID | / |
Family ID | 32682224 |
Filed Date | 2008-12-18 |
United States Patent
Application |
20080311117 |
Kind Code |
A1 |
Collins; Mary ; et
al. |
December 18, 2008 |
Antibodies against PD-1 and uses therefor
Abstract
This disclosure provides antibodies and antigen-binding
fragments that can act as agonists and/or antagonists of PD-1
(Programmed Death 1), thereby modulating immune responses in
general, and those mediated by TcR and CD28, in particular. The
disclosed compositions and methods may be used for example, in
treating autoimmune diseases, inflammatory disorders, allergies,
transplant rejection, cancer, and other immune system
disorders.
Inventors: |
Collins; Mary; (Natick,
MA) ; Wood; Clive R.; (Boston, MA) ; Carreno;
Beatriz M.; (Acton, MA) ; Luxenberg; Deborah;
(Melrose, MA) ; Jussif; Jason; (Salem, NH)
; Carter; Laura L.; (Medford, MA) ; Bennett;
Frances K.; (Sudbury, MA) ; Valge-Archer; Viia;
(Little Abington, GB) ; Andrews; John; (Little
Hadham Ware, GB) ; Russell; Caroline; (Royston,
GB) |
Correspondence
Address: |
WOLF GREENFIELD & SACKS, P.C.
600 ATLANTIC AVENUE
BOSTON
MA
02210-2206
US
|
Family ID: |
32682224 |
Appl. No.: |
11/893989 |
Filed: |
August 17, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10741481 |
Dec 22, 2003 |
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11893989 |
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60435354 |
Dec 23, 2002 |
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Current U.S.
Class: |
424/133.1 ;
424/130.1; 424/139.1; 424/173.1 |
Current CPC
Class: |
A61P 3/10 20180101; C07K
2317/76 20130101; A61P 31/00 20180101; A61P 25/00 20180101; A61P
37/06 20180101; C07K 2317/622 20130101; A61P 35/00 20180101; C07K
2317/73 20130101; A61P 37/04 20180101; A61P 37/02 20180101; C07K
16/2818 20130101; A61K 2039/505 20130101; C07K 16/2803 20130101;
A61P 19/02 20180101; A61P 1/04 20180101; A61P 43/00 20180101; A61P
37/08 20180101; A61P 29/00 20180101 |
Class at
Publication: |
424/133.1 ;
424/130.1; 424/139.1; 424/173.1 |
International
Class: |
A61K 39/395 20060101
A61K039/395; A61P 35/00 20060101 A61P035/00 |
Claims
1.-34. (canceled)
35. A method for treating a subject, the method comprising:
administering to a subject having a disorder or needing preventive
measures for a disorder an effective amount of a pharmaceutical
composition comprising an antibody, wherein the antibody comprises
an amino acid sequence as set out in SEQ ID NO: 19, SEQ ID NO: 25,
SEQ ID NO: 31, SEQ ID NO: 37, or SEQ ID NO: 52.
36. The method of claim 35, wherein the disorder is an immune
disorder or cancer.
37. The method of claim 35 wherein the disorder is cancer.
38. The method of claim 35 wherein the disorder is an immune
disorder selected from the group consisting of: an autoimmune
disorder, an immune response to a graft, and an allergic
reaction.
39. The method of claim 35 wherein the disorder is an immune
disorder selected from the group consisting of: rheumatoid
arthritis, multiple sclerosis, inflammatory bowel disease, Crohn's
disease, systemic lupus erythematosis, type I diabetes, transplant
rejection, graft-versus-host disease and hyperproliferative immune
disorders.
40. The method of any one of claims 35-39, wherein the subject is a
human.
41. The method of any one of claims 35-39, wherein the antibody
comprises an amino acid sequence selected from the group consisting
of SEQ ID NO: 2, SEQ ID NO: 4, SEQ ID NO: 6, SEQ ID NO: 8, SEQ ID
NO: 10, SEQ ID NO: 12, SEQ ID NO: 14, SEQ ID NO: 16, SEQ ID NO: 47,
and SEQ ID NO: 49.
42. The method of any one of claims 35-39, wherein the antibody
specifically binds to an amino acid sequence that is at least 95%
identical to any sequence of at least 100 contiguous amino acids of
at least one sequence selected from group consisting of SEQ ID NO:
41 and SEQ ID NO: 56.
43. The method of claim 35, wherein the antibody specifically binds
to the extracellular domain of PD-1 with an affinity constant
greater than 10.sup.7 M.sup.-1.
44. The method of claim 42, wherein the antibody inhibits the
binding of PD-L to PD-1 with an IC.sub.50 of less than 10 nM.
45. The method of any one of claims 35-39, wherein the antibody is
a human antibody.
46. The method of claim 35, wherein the antibody is IgG1 or
IgG4.
47. The method of claim 43, wherein the antibody is IgG1.lamda. or
IgG1.kappa..
48. The method of any one of claims 35-39, wherein the antibody is
PD1-17, PD1-28, PD1-33, PD1-35, or PD1-F2
49. The method of any one of claims 35-39, wherein the antibody is
produced by a method of making an antibody that specifically binds
to PD-1, wherein the method comprises: (a) providing a starting
repertoire of nucleic acids encoding a variable domain that either
includes a CDR3 to be replaced or lacks a CDR3 encoding region; (b)
combining the repertoire with a donor nucleic acid encoding an
amino acid sequence as set out in SEQ ID NO: 19, SEQ ID NO: 25, SEQ
ID NO: 31, SEQ ID NO: 37, or SEQ ID NO: 52, such that the donor
nucleic acid is inserted into the CDR3 region in the repertoire, so
as to provide a product repertoire of nucleic acids encoding a
variable domain; (c) expressing the nucleic acids of the product
repertoire; (d) selecting an antigen-binding fragment specific for
PD-1; and (e) recovering the specific antigen-binding fragment or
nucleic acid encoding the binding fragment.
Description
RELATED CASES
[0001] This application claims priority to U.S. Provisional
Application No. 60/435,354, filed Dec. 23, 2002, which is
incorporated herein by reference.
TECHNICAL FIELD
[0002] The technical field relates to modulation of immune
responses regulated by the Programmed Death 1 (PD-1) receptor.
BACKGROUND
[0003] An adaptive immune response involves activation, selection,
and clonal proliferation of two major classes of lymphocytes termed
T cells and B cells. After encountering an antigen, T cells
proliferate and differentiate into antigen-specific effector cells,
while B cells proliferate and differentiate into antibody-secreting
cells.
[0004] T cell activation is a multi-step process requiring several
signaling events between the T cell and an antigen-presenting cell
(APC). For T cell activation to occur, two types of signals must be
delivered to a resting T cell. The first type is mediated by the
antigen-specific T cell receptor (TcR), and confers specificity to
the immune response. The second, costimulatory, type regulates the
magnitude of the response and is delivered through accessory
receptors on the T cell.
[0005] A primary costimulatory signal is delivered through the
activating CD28 receptor upon engagement of its ligands B7-1 or
B7-2. In contrast, engagement of the inhibitory CTLA-4 receptor by
the same B7-1 or B7-2 ligands results in attenuation of T cell
response. Thus, CTLA-4 signals antagonize costimulation mediated by
CD28. At high antigen concentrations, CD28 costimulation overrides
the CTLA-4 inhibitory effect. Temporal regulation of the CD28 and
CTLA-4 expression maintains a balance between activating and
inhibitory signals and ensures the development of an effective
immune response, while safeguarding against the development of
autoimmunity.
[0006] Molecular homologues of CD28 and CTLA-4 and their B-7 like
ligands have been recently identified. ICOS is a CD28-like
costimulatory receptor. PD-1 (Programmed Death 1) is an inhibitory
receptor and a counterpart of CTLA-4. This disclosure relates to
modulation of immune responses mediated by the PD-1 receptor.
[0007] PD-1 is a 50-55 kDa type I transmembrane receptor that was
originally identified in a T cell line undergoing
activation-induced apoptosis. PD-1 is expressed on T cells, B
cells, and macrophages. The ligands for PD-1 are the B7 family
members PD-L1 (B7-H1) and PD-L2 (B7-DC).
[0008] PD-1 is a member of the immunoglobulin (Ig) superfamily that
contains a single 1 g V-like domain in its extracellular region.
The PD-1 cytoplasmic domain contains two tyrosines, with the most
membrane-proximal tyrosine (VAYEEL in mouse PD-1) located within an
ITIM (immuno-receptor tyrosine-based inhibitory motif). The
presence of an ITIM on PD-1 indicates that this molecule functions
to attenuate antigen receptor signaling by recruitment of
cytoplasmic phosphatases. Human and murine PD-1 proteins share
about 60% amino acid identity with conservation of four potential
N-glycosylation sites, and residues that define the Ig-V domain.
The ITIM in the cytoplasmic region and the ITIM-like motif
surrounding the carboxy-terminal tyrosine (TEYATI in human and
mouse) are also conserved between human and murine orthologues.
[0009] PD-1 is expressed on activated T cells, B cells, and
monocytes. Experimental data implicates the interactions of PD-1
with its ligands in downregulation of central and peripheral immune
responses. In particular, proliferation in wild-type T cells but
not in PD-1-deficient T cells is inhibited in the presence of
PD-L1. Additionally, PD-1-deficient mice exhibit an autoimmune
phenotype. PD-1 deficiency in the C57BL/6 mice results in chronic
progressive lupus-like glomerulonephritis and arthritis. In Balb/c
mice, PD-1 deficiency leads to severe cardiomyopathy due to the
presence of heart-tissue-specific self-reacting antibodies.
[0010] In general, a need exists to provide safe and effective
therapeutic methods for immune disorders such as, for example,
autoimmune diseases, inflammatory disorders, allergies, transplant
rejection, cancer, immune deficiency, and other immune
system-related disorders. Modulation of the immune responses
involved in these disorders can be accomplished by manipulation of
the PD-1 pathway.
SUMMARY
[0011] The present disclosure provides antibodies that can act as
agonists and/or antagonists of PD-1, thereby modulating immune
responses regulated by PD-1. The disclosure further provides
anti-PD-1 antibodies that comprise novel antigen-binding fragments.
Anti-PD-1 antibodies of the invention are capable of (a)
specifically binding to PD-1, including human PD-1; (b) blocking
PD-1 interactions with its natural ligand(s); or (c) performing
both functions. Furthermore, the antibodies may possess
immunomodulatory properties, i.e., they may be effective in
modulating the PD-1-associated downregulation of immune responses.
Depending on the method of use and the desired effect, the
antibodies may be used to either enhance or inhibit immune
responses.
[0012] Nonlimiting illustrative embodiments of the antibodies are
referred to as PD1-17, PD1-28, PD1-33, PD1-35, and PD1-F2. Other
embodiments comprise a V.sub.H and/or V.sub.L domain of the Fv
fragment of PD1-17, PD1-28, PD1-33, PD1-35, or PD1-F2. Further
embodiments comprise one or more complementarity determining
regions (CDRs) of any of these V.sub.H and V.sub.L domains. Other
embodiments comprise an H3 fragment of the V.sub.H domain of
PD1-17, PD1-28, PD1-33, PD1-35, or PD1-F2.
[0013] The disclosure also provides compositions comprising PD-1
antibodies, and their use in methods of modulating immune response,
including methods of treating humans or animals. In particular
embodiments, anti-PD-1 antibodies are used to treat or prevent
immune disorders by virtue of increasing or reducing the T cell
response mediated by TcR/CD28. Disorders susceptible to treatment
with compositions of the invention include but are not limited to
rheumatoid arthritis, multiple sclerosis, inflammatory bowel
disease, Crohn's disease, systemic lupus erythematosis, type I
diabetes, transplant rejection, graft-versus-host disease,
hyperproliferative immune disorders, cancer, and infectious
diseases.
[0014] Additionally, anti-PD-1 antibodies may be used
diagnostically to detect PD-1 or its fragments in a biological
sample. The amount of PD-1 detected may be correlated with the
expression level of PD-1, which, in turn, is correlated with the
activation status of immune cells (e.g., activated T cells, B
cells, and monocytes) in the subject.
[0015] The disclosure also provides isolated nucleic acids, which
comprise a sequence encoding a V.sub.H or V.sub.L domain from the
Fv fragment of PD1-17, PD1-28, PD1-33, PD1-35, or PD1-F2. Also
provided are isolated nucleic acids, which comprise a sequence
encoding one or more CDRs from any of the presently disclosed
V.sub.H and V.sub.L domains. The disclosure also provides vectors
and host cells comprising such nucleic acids.
[0016] The disclosure further provides a method of producing new
V.sub.H and V.sub.L domains and/or functional antibodies comprising
all or a portion of such domains derived from the V.sub.H or
V.sub.L domains of PD1-17, PD1-28, PD1-33, PD1-35, or PD1-F2.
[0017] Additional aspects of the disclosure will be set forth in
part in the description which follows, and in part will be obvious
from the description, or may be learned by practicing the
invention. The invention is set forth and particularly pointed out
in the appended claims, and the present disclosure should not be
construed as limiting the scope of the claims in any way. The
following detailed description includes exemplary representations
of various embodiments of the invention, which are not restrictive
of the invention, as claimed. The accompanying figures constitute a
part of this specification and, together with the description,
serve only to illustrate various embodiments and not limit the
invention. Citation of references is not an admission that these
references are prior art to the invention.
BRIEF DESCRIPTION OF THE FIGURES
[0018] FIGS. 1A and 1B show reactivity of scFv antibodies with
human PD-1 as determined by phage ELISA.
[0019] FIGS. 2A-2C show reactivity of IgG-converted antibodies with
human or mouse PD-1 as determined by ELISA.
[0020] FIG. 3 shows results of an ELISA demonstrating that selected
PD-1 antibodies inhibit binding of PD-L1 to PD-1.
[0021] FIG. 4 shows results of an ELISA demonstrating that
immunomodulatory PD-1 antibodies bind to distinct sites on PD-1 as
determined by cross-blocking ELISA assays.
[0022] FIG. 5 shows results of T-cell proliferation assays
demonstrating that co-engagement by TcR and anti-PD-1 antibody
PD1-17 or PD-L1.Fc reduces proliferation. Co-engagement by TcR and
anti-PD-1 J110 has no effect on proliferation.
[0023] FIG. 6 demonstrates enhanced proliferation of primary T
cells by PD1-17 in a soluble form.
DETAILED DESCRIPTION
Definitions
[0024] The term "antibody," as used in this disclosure, refers to
an immunoglobulin or a fragment or a derivative thereof, and
encompasses any polypeptide comprising an antigen-binding site,
regardless whether it is produced in vitro or in vivo. The term
includes, but is not limited to, polyclonal, monoclonal,
monospecific, polyspecific, non-specific, humanized, single-chain,
chimeric, synthetic, recombinant, hybrid, mutated, and grafted
antibodies. Unless otherwise modified by the term "intact," as in
"intact antibodies," for the purposes of this disclosure, the term
"antibody" also includes antibody fragments such as Fab,
F(ab').sub.2, Fv, scFv, Fd, dAb, and other antibody fragments that
retain antigen-binding function, i.e., the ability to bind PD-1
specifically. Typically, such fragments would comprise an
antigen-binding domain.
[0025] The terms "antigen-binding domain," "antigen-binding
fragment," and "binding fragment" refer to a part of an antibody
molecule that comprises amino acids responsible for the specific
binding between the antibody and the antigen. In instances, where
an antigen is large, the antigen-binding domain may only bind to a
part of the antigen. A portion of the antigen molecule that is
responsible for specific interactions with the antigen-binding
domain is referred to as "epitope" or "antigenic determinant."
[0026] An antigen-binding domain typically comprises an antibody
light chain variable region (V.sub.L) and an antibody heavy chain
variable region (V.sub.H), however, it does not necessarily have to
comprise both. For example, a so-called Fd antibody fragment
consists only of a V.sub.H domain, but still retains some
antigen-binding function of the intact antibody.
[0027] The term "repertoire" refers to a genetically diverse
collection of nucleotides derived wholly or partially from
sequences that encode expressed immunoglobulins. The sequences are
generated by in vivo rearrangement of, e.g., V, D, and J segments
for H chains and, e.g., V and J segment for L chains.
Alternatively, the sequences may be generated from a cell line by
in vitro stimulation, in response to which the rearrangement
occurs. Alternatively, part or all of the sequences may be obtained
by combining, e.g., unrearranged V segments with D and J segments,
by nucleotide synthesis, randomised mutagenesis, and other methods,
e.g., as disclosed in U.S. Pat. No. 5,565,332.
[0028] The terms "specific interaction" and "specific binding"
refer to two molecules forming a complex that is relatively stable
under physiologic conditions. Specific binding is characterized by
a high affinity and a low to moderate capacity as distinguished
from nonspecific binding which usually has a low affinity with a
moderate to high capacity. Typically, binding is considered
specific when the affinity constant K.sub.A is higher than 10.sup.6
M.sup.-1 or more preferably higher than 10.sup.8 M.sup.-1. If
necessary, non-specific binding can be reduced without
substantially affecting specific binding by varying the binding
conditions. The appropriate binding conditions such as
concentration of antibodies, ionic strength of the solution,
temperature, time allowed for binding, concentration of a blocking
agent (e.g., serum albumin, milk casein), etc., may be optimized by
a skilled artisan using routine techniques. Illustrative conditions
are set forth in Examples 1, 2, 4, 6, and 7.
[0029] The phrase "substantially as set out" means that the
relevant CDR, V.sub.H, or V.sub.L domain of the invention will be
either identical to or have only insubstantial differences in the
specified regions (e.g., a CDR), the sequence of which is set out.
Insubstantial differences include minor amino acid changes, such as
substitutions of 1 or 2 out of any 5 amino acids in the sequence of
a specified region.
[0030] The term "PD-1 activity" refers to one or more
immunoregulatory activities associated with PD-1. For example, PD-1
is a negative regulator of the TcR/CD28-mediated immune response.
Procedures for assessing the PD-1 activity in vivo and in vitro are
described in Examples 8, 9, and 10.
[0031] The terms "modulate," "immunomodulatory," and their cognates
refer to a reduction or an increase in the activity of PD-1
associated with downregulation of T cell responses due to its
interaction with an anti-PD-1 antibody, wherein the reduction or
increase is relative to the activity of PD-1 in the absence of the
same antibody. A reduction or an increase in activity is preferably
at least about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or
more. When PD-1 activity is reduced, the terms "modulatory" and
"modulate" are interchangeable with the terms "inhibitory" and
"inhibit." When PD-1 activity is increased, the terms "modulatory"
and "modulate" are interchangeable with the terms "activating" and
"activate." The activity of PD-1 can be determined quantitatively
using T cell proliferation assays as described in Examples 8 and
9.
[0032] The terms "treatment" and "therapeutic method" refer to both
therapeutic treatment and prophylactic/preventative measures. Those
in need of treatment may include individuals already having a
particular medical disorder as well as those who may ultimately
acquire the disorder (i.e., those needing preventative
measures).
[0033] The term "effective amount" refers to a dosage or amount
that is sufficient to reduce the activity of PD-1 to result in
amelioration of symptoms in a patient or to achieve a desired
biological outcome, e.g., increased cytolytic activity of T cells,
induction of immune tolerance, reduction or increase of the PD-1
activity associated with the negative regulation of T-cell mediated
immune response, etc.
[0034] The term "isolated" refers to a molecule that is
substantially free of its natural environment. For instance, an
isolated protein is substantially free of cellular material or
other proteins from the cell or tissue source from which it is
derived. The term "isolated" also refers to preparations where the
isolated protein is sufficiently pure to be administered as a
pharmaceutical composition, or at least 70-80% (w/w) pure, more
preferably, at least 80-90% (w/w) pure, even more preferably,
90-95% pure; and, most preferably, at least 95%, 96%, 97%, 98%,
99%, or 100% (w/w) pure.
Anti-PD-1 Antibodies
[0035] The disclosure provides anti-PD-1 antibodies that comprise
novel antigen-binding fragments.
[0036] In general, antibodies can be made, for example, using
traditional hybridoma techniques (Kohler and Milstein (1975)
Nature, 256: 495-499), recombinant DNA methods (U.S. Pat. No.
4,816,567), or phage display performed with antibody libraries
(Clackson et al. (1991) Nature, 352: 624-628; Marks et al. (1991)
J. Mol. Biol., 222: 581-597). For other antibody production
techniques, see also Antibodies: A Laboratory Manual, eds. Harlow
et al., Cold Spring Harbor Laboratory, 1988. The invention is not
limited to any particular source, species of origin, method of
production.
[0037] Intact antibodies, also known as immunoglobulins, are
typically tetrameric glycosylated proteins composed of two light
(L) chains of approximately 25 kDa each and two heavy (H) chains of
approximately 50 kDa each. Two types of light chain, designated as
the .lamda. chain and the .kappa. chain, are found in antibodies.
Depending on the amino acid sequence of the constant domain of
heavy chains, immunoglobulins can be assigned to five major
classes: A, D, E, G, and M, and several of these may be further
divided into subclasses (isotypes), e.g., IgG.sub.1, IgG.sub.2,
IgG.sub.3, IgG.sub.4, IgA.sub.1, and IgA.sub.2.
[0038] The subunit structures and three-dimensional configurations
of different classes of immunoglobulins are well known in the art.
For a review of antibody structure, see Harlow et al., supra.
Briefly, each light chain is composed of an N-terminal variable
domain (V.sub.L) and a constant domain (C.sub.L). Each heavy chain
is composed of an N-terminal variable domain (V.sub.H), three or
four constant domains (C.sub.H), and a hinge region. The C.sub.H
domain most proximal to V.sub.H is designated as C.sub.H1. The
V.sub.H and V.sub.L domains consist of four regions of relatively
conserved sequence called framework regions (FR1, FR2, FR3, and
FR4), which form a scaffold for three regions of hypervariable
sequence called complementarity determining regions (CDRs). The
CDRs contain most of the residues responsible for specific
interactions with the antigen. The three CDRs are referred to as
CDR1, CDR2, and CDR3. CDR constituents on the heavy chain are
referred to as H1, H2, and H3, while CDR constituents on the light
chain are referred to as L1, L2, and L3, accordingly. CDR3 and,
particularly H3, are the greatest source of molecular diversity
within the antigen-binding domain. H3, for example, can be as short
as two amino acid residues or greater than 26.
[0039] The Fab fragment (Fragment antigen-binding) consists of the
V.sub.H-C.sub.H1 and V.sub.L-C.sub.L domains covalently linked by a
disulfide bond between the constant regions. To overcome the
tendency of non-covalently linked V.sub.H and V.sub.L domains in
the Fv to dissociate when co-expressed in a host cell, a so-called
single chain (sc) Fv fragment (scFv) can be constructed. In a scFv,
a flexible and adequately long polypeptide links either the
C-terminus of the V.sub.H to the N-terminus of the V.sub.L or the
C-terminus of the V.sub.L to the N-terminus of the V.sub.H. Most
commonly, a 15-residue (Gly.sub.4Ser).sub.3 peptide is used as a
linker but other linkers are also known in the art.
[0040] Antibody diversity is a result of combinatorial assembly of
multiple germline genes encoding variable regions and a variety of
somatic events. The somatic events include recombination of
variable gene segments with diversity (D) and joining (J) gene
segments to make a complete V.sub.H region and the recombination of
variable and joining gene segments to make a complete V.sub.L
region. The recombination process itself is imprecise, resulting in
the loss or addition of amino acids at the V(D)J junctions. These
mechanisms of diversity occur in the developing B cell prior to
antigen exposure. After antigenic stimulation, the expressed
antibody genes in B cells undergo somatic mutation.
[0041] Based on the estimated number of germline gene segments, the
random recombination of these segments, and random V.sub.H-V.sub.L
pairing, up to 1.6.times.10.sup.7 different antibodies could be
produced (Fundamental Immunology, 3.sup.rd ed., ed. Paul, Raven
Press, New York, N.Y., 1993). When other processes which contribute
to antibody diversity (such as somatic mutation) are taken into
account, it is thought that upwards of 1.times.10.sup.10 different
antibodies could be potentially generated (Immunoglobulin Genes,
2.sup.nd ed., eds. Jonio et al., Academic Press, San Diego, Calif.,
1995). Because of the many processes involved in antibody
diversity, it is highly unlikely that independently generated
antibodies will have identical or even substantially similar amino
acid sequences in the CDRs.
[0042] The disclosure provides novel CDRs derived from human
immunoglobulin gene libraries. The structure for carrying a CDR
will generally be an antibody heavy or light chain or a portion
thereof, in which the CDR is located at a location corresponding to
the CDR of naturally occurring V.sub.H and V.sub.L. The structures
and locations of immunoglobulin variable domains may be determined,
for example, as described in Kabat et al., Sequences of Proteins of
Immunological Interest, No. 91-3242, National Institutes of Health
Publications, Bethesda, Md., 1991.
[0043] DNA and amino acid sequences of anti-PD-1 antibodies, their
scFv fragment, V.sub.H and V.sub.L domains, and CDRs are set forth
in the Sequence Listing and are enumerated as listed in Table 1.
Particular nonlimiting illustrative embodiments of the antibodies
are referred to as PD1-17, PD1-28, PD1-33, PD1-35, and PD1-F2. The
positions for each CDR within the V.sub.H and V.sub.L domains of
the illustrative embodiments are listed in Tables 2 and 3.
TABLE-US-00001 TABLE 1 DNA and Amino Acid (AA) Sequences of V.sub.H
and V.sub.L Domains and CDRs Sequence PD1-17 PD1-28 PD1-33 PD1-35
PD1-F2 V.sub.H DNA SEQ ID NO: 1 SEQ ID NO: 5 SEQ ID NO: 9 SEQ ID
NO: 13 SEQ ID NO: 46 V.sub.H AA SEQ ID NO: 2 SEQ ID NO: 6 SEQ ID
NO: 10 SEQ ID NO: 14 SEQ ID NO: 47 V.sub.L DNA SEQ ID NO: 3 SEQ ID
NO: 7 SEQ ID NO: 11 SEQ ID NO: 15 SEQ ID NO: 48 V.sub.L AA SEQ ID
NO: 4 SEQ ID NO: 8 SEQ ID NO: 12 SEQ ID NO: 16 SEQ ID NO: 49 H1 AA
SEQ ID NO: 17 SEQ ID NO: 23 SEQ ID NO: 29 SEQ ID NO: 35 SEQ ID NO:
50 H2 AA SEQ ID NO: 18 SEQ ID NO: 24 SEQ ID NO: 30 SEQ ID NO: 36
SEQ ID NO: 51 H3 AA SEQ ID NO: 19 SEQ ID NO: 25 SEQ ID NO: 31 SEQ
ID NO: 37 SEQ ID NO: 52 L1 AA SEQ ID NO: 20 SEQ ID NO: 26 SEQ ID
NO: 32 SEQ ID NO: 38 SEQ ID NO: 53 L2 AA SEQ ID NO: 21 SEQ ID NO:
27 SEQ ID NO: 33 SEQ ID NO: 39 SEQ ID NO: 54 L3 AA SEQ ID NO: 22
SEQ ID NO: 28 SEQ ID NO: 34 SEQ ID NO: 40 SEQ ID NO: 55
TABLE-US-00002 TABLE 2 Positions of Heavy Chain CDRs PD1-17 PD1-28
PD1-33 PD1-35 PD1-F2 CDR SEQ ID NO: 2 SEQ ID NO: 6 SEQ ID NO: 10
SEQ ID NO: 14 SEQ ID NO: 47 H1 31-42 31-35 31-35 31-37 34-42 H2
57-72 50-66 50-66 52-67 57-73 H3 105-117 99-108 99-108 100-116
106-114
TABLE-US-00003 TABLE 3 Positions of Light Chain CDRs PD1-17 PD1-28
PD1-33 PD1-35 PD1-F2 CDR SEQ ID NO: 4 SEQ ID NO: 8 SEQ ID NO: 12
SEQ ID NO: 16 SEQ ID NO: 49 L1 23-35 23-33 23-36 23-35 28-35 L2
51-57 49-55 52-58 51-57 54-61 L3 92-100 88-98 91-102 90-100
94-101
[0044] Anti-PD-1 antibodies may optionally comprise antibody
constant regions or parts thereof. For example, a V.sub.L domain
may have attached, at its C terminus, antibody light chain constant
domains including human C.kappa. or C.lamda. chains. Similarly, a
specific antigen-binding domain based on a V.sub.H domain may have
attached all or part of an immunoglobulin heavy chain derived from
any antibody isotope, e.g., IgG, IgA, IgE, and IgM and any of the
isotope sub-classes, which include but are not limited to,
IgG.sub.1 and IgG.sub.4. In the exemplary embodiments, PD1-17,
PD1-28, PD1-33, and PD1-35, antibodies comprise C-terminal
fragments of heavy and light chains of human IgG.sub.1.lamda.,
while PD1-F2 comprises C-terminal fragments of heavy and light
chains of human IgG.sub.1.kappa.. The DNA and amino acid sequences
for the C-terminal fragment of are well known in the art (see,
e.g., Kabat et al., Sequences of Proteins of Immunological
Interest, No. 91-3242, National Institutes of Health Publications,
Bethesda, Md., 1991). Nonlimiting exemplary sequences are set forth
in Table 4.
TABLE-US-00004 TABLE 4 C-Terminal Region DNA Amino acid IgG1 heavy
chain SEQ ID NO: 44 SEQ ID NO: 45 .lamda. light chain SEQ ID NO: 42
SEQ ID NO: 43 .kappa. light chain SEQ ID NO: 57 SEQ ID NO: 58
[0045] Certain embodiments comprise a V.sub.H and/or V.sub.L domain
of an Fv fragment from PD1-17, PD1-28, PD1-33, PD1-35, and PD1-F2.
Further embodiments comprise at least one CDR of any of these
V.sub.H and V.sub.L domains. Antibodies, comprising at least one of
the CDR sequences set out in SEQ ID NO:2, SEQ ID NO:4, SEQ ID NO:6,
SEQ ID NO:8, SEQ ID NO:10, SEQ ID NO:12, SEQ ID NO:14, SEQ ID
NOs:16-40, SEQ ID NO:47, or SEQ ID NO:49 are encompassed within the
scope of this invention. An embodiment, for example, comprises an
H3 fragment of the V.sub.H domain of antibodies chosen from at
least one of PD1-17, PD1-28, PD1-33, PD1-35, and PD1-F2.
[0046] In certain embodiments, the V.sub.H and/or V.sub.L domains
may be germlined, i.e., the framework regions (FRs) of these
domains are mutated using conventional molecular biology techniques
to match those produced by the germline cells. In other
embodiments, the framework sequences remain diverged from the
consensus germline sequences.
[0047] In certain embodiments, the antibodies specifically bind an
epitope within the extracellular domain of human PD-1. The
predicted extracellular domain consists of a sequence from about
amino acid 21 to about amino acid 170 of SEQ ID NO:41 (Swissport
Accession No. Q15116). In certain other embodiments, the antibodies
specifically bind an epitope within the extracellular domain of
mouse PD-1, with an affinity of more than 10.sup.7 M.sup.-1, and
preferably more than 10.sup.8 M.sup.-1. The amino acid sequence of
mouse PD-1 is set out in SEQ ID NO:56 (Accession No.
NM.sub.--008798) and is as a whole about 60% identical to its human
counterpart. In further embodiments, antibodies of the invention
bind to the PD-L-binding domain of PD-1.
[0048] It is contemplated that antibodies of the invention may also
bind with other proteins, including, for example, recombinant
proteins comprising all or a portion of the PD-1 extracellular
domain.
[0049] One of ordinary skill in the art will recognize that the
antibodies of this invention may be used to detect, measure, and
inhibit proteins that differ somewhat from PD-1. The antibodies are
expected to retain the specificity of binding so long as the target
protein comprises a sequence which is at least about 60%, 70%, 80%,
90%, 95%, or more identical to any sequence of at least 100, 80,
60, 40, or 20 of contiguous amino acids in the sequence set forth
SEQ ID NO:41. The percent identity is determined by standard
alignment algorithms such as, for example, Basic Local Alignment
Tool (BLAST) described in Altshul et al. (1990) J. Mol. Biol., 215:
403-410, the algorithm of Needleman et al. (1970) J. Mol. Biol.,
48: 444-453, or the algorithm of Meyers et al. (1988) Comput. Appl.
Biosci., 4: 11-17.
[0050] In addition to the sequence homology analyses, epitope
mapping (see, e.g., Epitope Mapping Protocols, ed. Morris, Humana
Press, 1996) and secondary and tertiary structure analyses can be
carried out to identify specific 3D structures assumed by the
disclosed antibodies and their complexes with antigens. Such
methods include, but are not limited to, X-ray crystallography
(Engstom (1974) Biochem. Exp. Biol., 11:7-13) and computer modeling
of virtual representations of the presently disclosed antibodies
(Fletterick et al. (1986) Computer Graphics and Molecular Modeling,
in Current Communications in Molecular Biology, Cold Spring Harbor
Laboratory, Cold Spring Harbor, N.Y.).
Derivatives
[0051] This disclosure also provides a method for obtaining an
antibody specific for PD-1. CDRs in such antibodies are not limited
to the specific sequences of V.sub.H and V.sub.L identified in
Table 1 and may include variants of these sequences that retain the
ability to specifically bind PD-1. Such variants may be derived
from the sequences listed in Table 1 by a skilled artisan using
techniques well known in the art. For example, amino acid
substitutions, deletions, or additions, can be made in the FRs
and/or in the CDRs. While changes in the FRs are usually designed
to improve stability and immunogenicity of the antibody, changes in
the CDRs are typically designed to increase affinity of the
antibody for its target. Variants of FRs also include naturally
occurring immunoglobulin allotypes. Such affinity-increasing
changes may be determined empirically by routine techniques that
involve altering the CDR and testing the affinity antibody for its
target. For example, conservative amino acid substitutions can be
made within any one of the disclosed CDRs. Various alterations can
be made according to the methods described in Antibody Engineering,
2.sup.nd ed., Oxford University Press, ed. Borrebaeck, 1995. These
include but are not limited to nucleotide sequences that are
altered by the substitution of different codons that encode a
functionally equivalent amino acid residue within the sequence,
thus producing a "silent" change. For example, the nonpolar amino
acids include alanine, leucine, isoleucine, valine, proline,
phenylalanine, tryptophan, and methionine. The polar neutral amino
acids include glycine, serine, threonine, cysteine, tyrosine,
asparagine, and glutamine. The positively charged (basic) amino
acids include arginine, lysine, and histidine. The negatively
charged (acidic) amino acids include aspartic acid and glutamic
acid. Substitutes for an amino acid within the sequence may be
selected from other members of the class to which the amino acid
belongs (see Table 5). Furthermore, any native residue in the
polypeptide may also be substituted with alanine (see, e.g.,
MacLennan et al. (1998) Acta Physiol. Scand. Suppl. 643:55-67;
Sasaki et al. (1998) Adv. Biophys. 35:1-24).
[0052] Derivatives and analogs of antibodies of the invention can
be produced by various techniques well known in the art, including
recombinant and synthetic methods (Maniatis (1990) Molecular
Cloning, A Laboratory Manual, 2.sup.nd ed., Cold Spring Harbor
Laboratory, Cold Spring Harbor, N.Y., and Bodansky et al. (1995)
The Practice of Peptide Synthesis, 2.sup.nd ed., Spring Verlag,
Berlin, Germany).
TABLE-US-00005 TABLE 5 Original Exemplary Typical Residues
Substitutions Substitutions Ala (A) Val, Leu, Ile Val Arg (R) Lys,
Gln, Asn Lys Asn (N) Gln Gln Asp (D) Glu Glu Cys (C) Ser, Ala Ser
Gln (Q) Asn Asn Gly (G) Pro, Ala Ala His (H) Asn, Gln, Lys, Arg Arg
Ile (I) Leu, Val, Met, Ala, Phe, Norleucine Leu Leu (L) Norleucine,
Ile, Val, Met, Ala, Phe Ile Lys (K) Arg, 1,4-Diamino-butyric Acid,
Gln, Asn Arg Met (M) Leu, Phe, Ile Leu Phe (F) Leu, Val, Ile, Ala,
Tyr Leu Pro (P) Ala Gly Ser (S) Thr, Ala, Cys Thr Thr (T) Ser Ser
Trp (W) Tyr, Phe Tyr Tyr (Y) Trp, Phe, Thr, Ser Phe Val (V) Ile,
Met, Leu, Phe, Ala, Norleucine Leu
[0053] In one embodiment, a method for making a V.sub.H domain
which is an amino acid sequence variant of a V.sub.H domain of the
invention comprises a step of adding, deleting, substituting, or
inserting one or more amino acids in the amino acid sequence of the
presently disclosed V.sub.H domain, optionally combining the
V.sub.H domain thus provided with one or more V.sub.L domains, and
testing the V.sub.H domain or V.sub.H/V.sub.L combination or
combinations for a specific binding to PD-1 or and, optionally,
testing the ability of such antigen-binding domain to modulate PD-1
activity. The V.sub.L domain may have an amino acid sequence that
is identical or is substantially as set out according to Table
1.
[0054] An analogous method can be employed in which one or more
sequence variants of a V.sub.L domain disclosed herein are combined
with one or more V.sub.H domains.
[0055] A further aspect of the disclosure provides a method of
preparing antigen-binding fragment that specifically binds with
PD-1. The method comprises:
[0056] (a) providing a starting repertoire of nucleic acids
encoding a V.sub.H domain that either includes a CDR3 to be
replaced or lacks a CDR3 encoding region;
[0057] (b) combining the repertoire with a donor nucleic acid
encoding an amino acid sequence substantially as set out herein for
a V.sub.H CDR3 (i.e., H3) such that the donor nucleic acid is
inserted into the CDR3 region in the repertoire, so as to provide a
product repertoire of nucleic acids encoding a V.sub.H domain;
[0058] (c) expressing the nucleic acids of the product
repertoire;
[0059] (d) selecting a binding fragment specific for PD-1; and
[0060] (e) recovering the specific binding fragment or nucleic acid
encoding it.
[0061] Again, an analogous method may be employed in which a
V.sub.L CDR3 (i.e., L3) of the invention is combined with a
repertoire of nucleic acids encoding a V.sub.L domain, which either
include a CDR3 to be replaced or lack a CDR3 encoding region. The
donor nucleic acid may be selected from nucleic acids encoding an
amino acid sequence substantially as set out in SEQ ID NO:1740 or
SEQ ID NO:50-55.
[0062] A sequence encoding a CDR of the invention (e.g., CDR3) may
be introduced into a repertoire of variable domains lacking the
respective CDR (e.g., CDR3), using recombinant DNA technology, for
example, using methodology described by Marks et al.
(Bio/Technology (1992) 10: 779-783). In particular, consensus
primers directed at or adjacent to the 5' end of the variable
domain area can be used in conjunction with consensus primers to
the third framework region of human V.sub.H genes to provide a
repertoire of V.sub.H variable domains lacking a CDR3. The
repertoire may be combined with a CDR3 of a particular antibody.
Using analogous techniques, the CDR3-derived sequences may be
shuffled with repertoires of V.sub.H or V.sub.L domains lacking a
CDR3, and the shuffled complete V.sub.H or V.sub.L domains combined
with a cognate V.sub.L or V.sub.H domain to make the PD-1-specific
antibodies of the invention. The repertoire may then be displayed
in a suitable host system such as the phage display system such as
described in WO92/01047 so that suitable antigen-binding fragments
can be selected.
[0063] Analogous shuffling or combinatorial techniques are also
disclosed by Stemmer (Nature (1994) 370: 389-391), who describes
the technique in relation to a .beta.-lactamase gene but observes
that the approach may be used for the generation of antibodies.
[0064] In further embodiments, one may generate novel V.sub.H or
V.sub.L regions carrying one or more sequences derived from the
sequences disclosed herein using random mutagenesis of one or more
selected V.sub.H and/or V.sub.L genes. One such technique,
error-prone PCR, is described by Gram et al. (Proc. Nat. Acad. Sci.
U.S.A. (1992) 89: 3576-3580).
[0065] Another method that may be used is to direct mutagenesis to
CDRs of V.sub.H or V.sub.L genes. Such techniques are disclosed by
Barbas et al. (Proc. Nat. Acad. Sci. U.S.A. (1994) 91: 3809-3813)
and Schier et al. (J. Mol. Biol. (1996) 263: 551-567).
[0066] Similarly, one or more, or all three CDRs may be grafted
into a repertoire of V.sub.H or V.sub.L domains, which are then
screened for an antigen-binding fragment specific for PD-1.
[0067] A portion of an immunoglobulin variable domain will comprise
at least one of the CDRs substantially as set out herein and,
optionally, intervening framework regions from the scF.sub.v
fragments as set out herein. The portion may include at least about
50% of either or both of FR1 and FR4, the 50% being the C-terminal
50% of FR1 and the N-terminal 50% of FR4. Additional residues at
the N-terminal or C-terminal end of the substantial part of the
variable domain may be those not normally associated with naturally
occurring variable domain regions. For example, construction of
antibodies by recombinant DNA techniques may result in the
introduction of N- or C-terminal residues encoded by linkers
introduced to facilitate cloning or other manipulation steps. Other
manipulation steps include the introduction of linkers to join
variable domains to further protein sequences including
immunoglobulin heavy chain constant regions, other variable domains
(for example, in the production of diabodies), or proteinaceous
labels as discussed in further detail below.
[0068] Although the embodiments illustrated in the Examples
comprise a "matching" pair of V.sub.H and V.sub.L domains, a
skilled artisan will recognize that alternative embodiments may
comprise antigen-binding fragments containing only a single CDR
from either V.sub.L or V.sub.H domain. Either one of the single
chain specific binding domains can be used to screen for
complementary domains capable of forming a two-domain specific
antigen-binding fragment capable of, for example, binding to PD-1.
The screening may be accomplished by phage display screening
methods using the so-called hierarchical dual combinatorial
approach disclosed in WO92/01047, in which an individual colony
containing either an H or L chain clone is used to infect a
complete library of clones encoding the other chain (L or H) and
the resulting two-chain specific binding domain is selected in
accordance with phage display techniques as described.
[0069] Anti-PD1 antibodies described herein can be linked to
another functional molecule, e.g., another peptide or protein
(albumin, another antibody, etc.), toxin, radioisotope, cytotoxic
or cytostatic agents. For example, the antibodies can be linked by
chemical cross-linking or by recombinant methods. The antibodies
may also be linked to one of a variety of nonproteinaceous
polymers, e.g., polyethylene glycol, polypropylene glycol, or
polyoxyalkylenes, in the manner set forth in U.S. Pat. No.
4,640,835; 4,496,689; 4,301,144; 4,670,417; 4,791,192; or
4,179,337. The antibodies can be chemically modified by covalent
conjugation to a polymer, for example, to increase their
circulating half-life. Exemplary polymers and methods to attach
them are also shown in U.S. Pat. Nos. 4,766,106; 4,179,337;
4,495,285, and 4,609,546.
[0070] The disclosed antibodies may also be altered to have a
glycosylation pattern that differs from the native pattern. For
example, one or more carbohydrate moieties can be deleted and/or
one or more glycosylation sites added to the original antibody.
Addition of glycosylation sites to the presently disclosed
antibodies may be accomplished by altering the amino acid sequence
to contain glycosylation site consensus sequences known in the art.
Another means of increasing the number of carbohydrate moieties on
the antibodies is by chemical or enzymatic coupling of glycosides
to the amino acid residues of the antibody. Such methods are
described in WO 87/05330 and in Aplin et al. (1981) CRC Crit. Rev.
Biochem., 22: 259-306. Removal of any carbohydrate moieties from
the antibodies may be accomplished chemically or enzymatically, for
example, as described by Hakimuddin et al. (1987) Arch. Biochem.
Biophys., 259: 52; and Edge et al. (1981) Anal. Biochem., 118: 131
and by Thotakura et al. (1987) Meth. Enzymol., 138: 350. The
antibodies may also be tagged with a detectable, or functional,
label. Detectable labels include radiolabels such as .sup.131I or
.sup.99Tc, which may also be attached to antibodies using
conventional chemistry. Detectable labels also include enzyme
labels such as horseradish peroxidase or alkaline phosphatase.
Detectable labels further include chemical moieties such as biotin,
which may be detected via binding to a specific cognate detectable
moiety, e.g., labeled avidin.
[0071] Antibodies, in which CDR sequences differ only
insubstantially from those set out in SEQ ID NO:2, SEQ ID NO:4, SEQ
ID NO:6, SEQ ID NO:8, SEQ ID NO:10, SEQ ID NO:12, SEQ ID NO:14, SEQ
ID NOs:1640, SEQ ID NO:47, or SEQ ID NO:49 are encompassed within
the scope of this invention. Typically, an amino acid is
substituted by a related amino acid having similar charge,
hydrophobic, or stereochemical characteristics. Such substitutions
would be within the ordinary skills of an artisan. Unlike in CDRs,
more substantial changes can be made in FRs without adversely
affecting the binding properties of an antibody. Changes to FRs
include, but are not limited to, humanizing a non-human derived or
engineering certain framework residues that are important for
antigen contact or for stabilizing the binding site, e.g., changing
the class or subclass of the constant region, changing specific
amino acid residues which might alter the effector function such as
Fc receptor binding, e.g., as described in U.S. Pat. Nos. 5,624,821
and 5,648,260 and Lund et al. (1991) J. Immun. 147: 2657-2662 and
Morgan et al. (1995) Immunology 86: 319-324, or changing the
species from which the constant region is derived.
[0072] One of skill in the art will appreciate that the
modifications described above are not all-exhaustive, and that many
other modifications would obvious to a skilled artisan in light of
the teachings of the present disclosure.
Nucleic Acids, Cloning and Expression Systems
[0073] The present disclosure further provides isolated nucleic
acids encoding the disclosed antibodies. The nucleic acids may
comprise DNA or RNA and may be wholly or partially synthetic or
recombinant. Reference to a nucleotide sequence as set out herein
encompasses a DNA molecule with the specified sequence, and
encompasses a RNA molecule with the specified sequence in which U
is substituted for T, unless context requires otherwise.
[0074] The nucleic acids provided herein comprise a coding sequence
for a CDR, a V.sub.H domain, and/or a V.sub.L domain disclosed
herein.
[0075] The present disclosure also provides constructs in the form
of plasmids, vectors, phagemids, transcription or expression
cassettes which comprise at least one nucleic acid encoding a CDR,
a V.sub.H domain, and/or a V.sub.L domain disclosed here.
[0076] The disclosure further provides a host cell which comprises
one or more constructs as above.
[0077] Also provided are nucleic acids encoding any CDR (H1, H2,
H3, L1, L2, or L3), V.sub.H or V.sub.L domain, as well as methods
of making of the encoded products. The method comprises expressing
the encoded product from the encoding nucleic acid. Expression may
be achieved by culturing under appropriate conditions recombinant
host cells containing the nucleic acid. Following production by
expression a V.sub.H or V.sub.L domain, or specific binding member
may be isolated and/or purified using any suitable technique, then
used as appropriate.
[0078] Antigen-binding fragments, V.sub.H and/or V.sub.L domains,
and encoding nucleic acid molecules and vectors may be isolated
and/or purified from their natural environment, in substantially
pure or homogeneous form, or, in the case of nucleic acid, free or
substantially free of nucleic acid or genes of origin other than
the sequence encoding a polypeptide with the required function.
[0079] Systems for cloning and expression of a polypeptide in a
variety of different host cells are well known in the art. For
cells suitable for producing antibodies, see Gene Expression
Systems, Academic Press, eds. Fernandez et al., 1999. Briefly,
suitable host cells include bacteria, plant cells, mammalian cells,
and yeast and baculovirus systems. Mammalian cell lines available
in the art for expression of a heterologous polypeptide include
Chinese hamster ovary cells, HeLa cells, baby hamster kidney cells,
NS0 mouse myeloma cells, and many others. A common bacterial host
is E. coli. Any protein expression system compatible with the
invention may be used to produce the disclosed antibodies. Suitable
expression systems include transgenic animals described in Gene
Expression Systems, Academic Press, eds. Fernandez et al.,
1999.
[0080] Suitable vectors can be chosen or constructed, so that they
contain appropriate regulatory sequences, including promoter
sequences, terminator sequences, polyadenylation sequences,
enhancer sequences, marker genes and other sequences as
appropriate. Vectors may be plasmids or viral, e.g., phage, or
phagemid, as appropriate. For further details see, for example,
Sambrook et al., Molecular Cloning: A Laboratory Manual, 2.sup.nd
ed., Cold Spring Harbor Laboratory Press, 1989. Many known
techniques and protocols for manipulation of nucleic acid, for
example, in preparation of nucleic acid constructs, mutagenesis,
sequencing, introduction of DNA into cells and gene expression, and
analysis of proteins, are described in detail in Current Protocols
in Molecular Biology, 2.sup.nd Edition, eds. Ausubel et al., John
Wiley & Sons, 1992.
[0081] A further aspect of the disclosure provides a host cell
comprising a nucleic acid as disclosed here. A still further aspect
provides a method comprising introducing such nucleic acid into a
host cell. The introduction may employ any available technique. For
eukaryotic cells, suitable techniques may include calcium phosphate
transfection, DEAE-Dextran, electroporation, liposome-mediated
transfection and transduction using retrovirus or other virus,
e.g., vaccinia or, for insect cells, baculovirus. For bacterial
cells, suitable techniques may include calcium chloride
transformation, electroporation and transfection using
bacteriophage. The introduction of the nucleic acid into the cells
may be followed by causing or allowing expression from the nucleic
acid, e.g., by culturing host cells under conditions for expression
of the gene.
Methods of Use
[0082] The disclosed anti-PD-1 antibodies are capable of modulating
the PD-1-associated downregulation of the immune responses. In
particular embodiments, the immune response is TcR/CD28-mediated.
The disclosed antibodies can act as either agonists or antagonists
of PD-1, depending on the method of their use. The antibodies can
be used to prevent, diagnose, or treat medical disorders in
mammals, especially, in humans. Antibodies of the invention can
also be used for isolating PD-1 or PD-1-expressing cells.
Furthermore, the antibodies can be used to treat a subject at risk
of or susceptible to a disorder or having a disorder associated
with aberrant PD-1 expression or function.
[0083] Antibodies of the invention can be used in methods for
induction of tolerance to a specific antigen (e.g., a therapeutic
protein). In one embodiment, tolerance is induced against a
specific antigen by co-administration of antigen and an anti-PD-1
antibody of the invention. For example, patients that received
Factor VIII frequently generate antibodies to this protein;
co-administration of an anti-PD-1 antibody of the invention in
combination with recombinant Factor VIII is expected to result in
the downregulation of immune responses to this clotting factor.
[0084] Antibodies of the invention can be used in circumstances
where a reduction in the level of immune response may be desirable,
for example, in certain types of allergy or allergic reactions
(e.g., by inhibition of IgE production), autoimmune diseases (e.g.,
rheumatoid arthritis, type I diabetes mellitus, multiple sclerosis,
inflammatory bowel disease, Crohn's disease, and systemic lupus
erythematosis), tissue, skin and organ transplant rejection, and
graft-versus-host disease (GVHD).
[0085] When diminished immune response is desirable, the anti-PD-1
antibodies of the invention may be used as agonists to PD-1 in
order to enhance the PD-1-associated attenuation of the immune
response. In these embodiments, co-presentation and physical
proximity between positive (i.e., mediated by an antigen receptor,
e.g., TcR or BcR) and negative (i.e., PD-1) signals are required.
The preferred distance is less than or comparable to the size of a
naturally occurring antigen-presenting cell, i.e., less than about
100 .mu.m; more preferably, less than about 50 .mu.m; and most
preferably, less than about 20 .mu.m.
[0086] In some embodiments, the positive (activating) and the
negative (inhibiting) signals are provided by a ligand or
antibodies immobilized on solid support matrix, or a carrier. In
various embodiments, the solid support matrix may be composed of
polymer such as activated agarose, dextran, cellulose,
polyvinylidene fluoride (PVDF). Alternatively, the solid support
matrix may be based on silica or plastic polymers, e.g., as nylon,
dacron, polystyrene, polyacrylates, polyvinyls, teflons, etc.
[0087] The matrix can be implanted into the spleen of a patient.
Alternatively, the matrix may be used for the ex vivo incubation of
T cells obtained from a patient, which are then separated and
implanted back into the patient. The matrix may also be made from a
biodegradable material such polyglycolic acid,
polyhydroxyalkanoate, collagen, or gelatin so that they can be
injected into the patient's peritoneal cavity, and dissolve after
some time following the injection. The carrier can be shaped to
mimic a cell (e.g., bead or microsphere).
[0088] In some embodiments, the positive signal is delivered by a
T-cell-activating anti-CD3 antibody, which binds TcR. Activating
anti-CD3 antibodies are known in the art (see, for example, U.S.
Pat. Nos. 6,405,696 and 5,316,763). The ratio between the
activating TcR signal and negative PD-1 signal is determined
experimentally using conventional procedures known in the art or as
described in Examples 8, 9, and 10.
[0089] Under certain circumstances, it may be desirable to elicit
or enhance a patient's immune response in order to treat an immune
disorder or cancer. The disorders being treated or prevented by the
disclosed methods include but are not limited to infections with
microbes (e.g. bacteria), viruses (e.g., systemic viral infections
such as influenza, viral skin diseases such as herpes or shingles),
or parasites; and cancer (e.g., melanoma and prostate cancers).
[0090] Stimulation of T cell activation with anti-PD-1 antibodies
enhances T-T cell responses. In such cases, antibodies act as
antagonists of PD-1. Thus, in some embodiments, the antibodies can
be used to inhibit or reduce the downregulatory activity associated
with PD-1, i.e., the activity associated with downregulation of
TcR/CD28-mediated immune response. In these embodiments, the
antibodies are not coupled to a positive signal such as the
TcR-mediated stimulation, e.g., the antibodies are in their
soluble, support-unbound, form. As demonstrated in the Examples, a
blockade of PD-1/PD-L interaction with antagonizing anti-PD-1
antibodies leads to enhanced T cell proliferative responses,
consistent with a downregulatory role for the PD-1 pathway in T-T
interactions. In various embodiments, the antibodies inhibit
binding of PD-L to PD-1 with an IC.sub.50 of less than 10 nM, and
more preferably less then 5 nM, and most preferably less than 1 nM.
Inhibition of PD-L binding can be measured as described in Example
6 or using techniques known in the art.
[0091] The antibodies or antibody compositions of the present
invention are administered in therapeutically effective amounts.
Generally, a therapeutically effective amount may vary with the
subject's age, condition, and sex, as well as the severity of the
medical condition of the subject. A therapeutically effective
amount of antibody ranges from about 0.001 to about 30 mg/kg body
weight, preferably from about 0.01 to about 25 mg/kg body weight,
from about 0.1 to about 20 mg/kg body weight, or from about 1 to
about 10 mg/kg. The dosage may be adjusted, as necessary, to suit
observed effects of the treatment. The appropriate dose is chosen
based on clinical indications by a treating physician.
[0092] The antibodies may given as a bolus dose, to maximize the
circulating levels of antibodies for the greatest length of time
after the dose. Continuous infusion may also be used after the
bolus dose.
[0093] Immune cells (e.g., activated T cells, B cells, or
monocytes) can also be isolated from a patient and incubated ex
vivo with antibodies of the invention. In some embodiments, immune
responses can be inhibited by removing immune cells from a subject,
contacting the immune cells in vitro with an anti-PD-1 antibody of
the invention concomitantly with activation of the immune cells
(e.g., by antibodies to the TcR and/or BcR antigen receptor). In
such embodiments, the anti-PD-1 antibody should be used in a
multivalent form such that PD-1 molecules on the surface of an
immune cell become "crosslinked" upon binding to such antibodies.
For example, the anti-PD-1 antibodies can be bound to solid
support, such as beads, or crosslinked via a secondary antibody.
The immune cells may be then isolated using methods known in the
art and reimplanted into the patient.
[0094] In another aspect, the antibodies of the invention can be
used as a targeting agent for delivery of another therapeutic or a
cytotoxic agent (e.g., a toxin) to a cell expressing PD-1. The
method includes administering an anti-PD-1 antibody coupled to a
therapeutic or a cytotoxic agent or under conditions that allow
binding of the antibody to PD-1.
[0095] The antibodies of the invention may also be used to detect
the presence of PD-1 in biological samples. The amount of PD-1
detected may be correlated with the expression level of PD-1,
which, in turn, is correlated with the activation status of immune
cells (e.g., activated T cells, B cells, and monocytes) in the
subject.
[0096] Detection methods that employ antibodies are well known in
the art and include, for example, ELISA, radioimmunoassay,
immunoblot, Western blot, immunofluorescence, immunoprecipitation.
The antibodies may be provided in a diagnostic kit that
incorporates one or more of these techniques to detect PD-1. Such a
kit may contain other components, packaging, instructions, or other
material to aid the detection of the protein.
[0097] Where the antibodies are intended for diagnostic purposes,
it may be desirable to modify them, for example, with a ligand
group (such as biotin) or a detectable marker group (such as a
fluorescent group, a radioisotope or an enzyme). If desired, the
antibodies of the invention may be labeled using conventional
techniques. Suitable detectable labels include, for example,
fluorophores, chromophores, radioactive atoms, electron-dense
reagents, enzymes, and ligands having specific binding partners.
Enzymes are typically detected by their activity. For example,
horseradish peroxidase can be detected by its ability to convert
tetramethylbenzidine (TMB) to a blue pigment, quantifiable with a
spectrophotometer. For detection, suitable binding partners
include, but are not limited to, biotin and avidin or streptavidin,
IgG and protein A, and the numerous receptor-ligand couples known
in the art. Other permutations and possibilities will be readily
apparent to those of ordinary skill in the art, and are considered
as equivalents within the scope of the instant invention.
[0098] Antibodies of the invention can be used in screening methods
to identify inhibitors of the PD-1 pathway effective as
therapeutics. In such a screening assay, a first binding mixture is
formed by combining PD-1 and an antibody of the invention; and the
amount of binding in the first binding mixture (M.sub.0) is
measured. A second binding mixture is also formed by combining
PD-1, the antibody, and the compound or agent to be screened, and
the amount of binding in the second binding mixture (M.sub.1) is
measured. A compound to be tested may be another anti-PD-1
antibody, as illustrated in the Examples. The amounts of binding in
the first and second binding mixtures are then compared, for
example, by calculating the M.sub.1/M.sub.0 ratio. The compound or
agent is considered to be capable of modulating a PD-1-associated
downregulation of immune responses if a decrease in binding in the
second binding mixture as compared to the first binding mixture is
observed. The formulation and optimization of binding mixtures is
within the level of skill in the art, such binding mixtures may
also contain buffers and salts necessary to enhance or to optimize
binding, and additional control assays may be included in the
screening assay of the invention. Compounds found to reduce the
PD-1-antibody binding by at least about 10% (i.e.,
M.sub.1/M.sub.0<0.9), preferably greater than about 30% may thus
be identified and then, if desired, secondarily screened for the
capacity to ameliorate a disorder in other assays or animal models
as described below. The strength of the binding between PD-1 and an
antibody can be measured using, for example, an enzyme-linked
immunoadsorption assay (ELISA), radio-immunoassay (RIA), surface
plasmon resonance-based technology (e.g., Biacore), all of which
are techniques well known in the art.
[0099] The compound may then be tested in vitro as described in the
Examples or in an animal model (see, generally, Immunologic Defects
in Laboratory Animals, eds. Gershwin et al., Plenum Press, 1981),
for example, such as the following: the SWR.times.NZB (SNF1)
transgenic mouse model (Uner et al. (1998) J. Autoimmune. 11(3):
233-240), the KRN transgenic mouse (K/B.times.N) model (Ji et al.
(1999) Immunol. Rev. 169: 139); NZB.times.NZW (B/W) mice, a model
for SLE (Riemekasten et al. (2001) Arthritis Rheum., 44(10):
2435-2445); experimental autoimmune encephalitis (EAE) in mouse, a
model for multiple sclerosis (Tuohy et al. (1988) J. Immunol. 141:
1126-1130, Sobel et al. (1984) J. Immunol. 132: 2393-2401, and
Traugott, Cell Immunol. (1989) 119: 114-129); the NOD mouse model
of diabetes (Baxter et al. (1991) Autoimmunity, 9(1): 61-67),
etc.).
[0100] Preliminary doses as, for example, determined according to
animal tests, and the scaling of dosages for human administration
is performed according to art-accepted practices. Toxicity and
therapeutic efficacy can be determined by standard pharmaceutical
procedures in cell cultures or experimental animals. The data
obtained from the cell culture assays or animal studies can be used
in formulating a range of dosage for use in humans. Therapeutically
effective dosages achieved in one animal model can be converted for
use in another animal, including humans, using conversion factors
known in the art (see, e.g., Freireich et al. (1966) Cancer
Chemother. Reports, 50(4): 219-244).
Pharmaceutical Compositions and Methods of Administration
[0101] The disclosure provides compositions comprising anti-PD-1
antibodies. Such compositions may be suitable for pharmaceutical
use and administration to patients. The compositions typically
comprise one or more antibodies of the present invention and a
pharmaceutically acceptable excipient. The phrase "pharmaceutically
acceptable excipient" includes any and all solvents, dispersion
media, coatings, antibacterial agents and antifungal agents,
isotonic agents, and absorption delaying agents, and the like, that
are compatible with pharmaceutical administration. The use of such
media and agents for pharmaceutically active substances is well
known in the art. The compositions may also contain other active
compounds providing supplemental, additional, or enhanced
therapeutic functions. The pharmaceutical compositions may also be
included in a container, pack, or dispenser together with
instructions for administration.
[0102] A pharmaceutical composition of the invention is formulated
to be compatible with its intended route of administration. Methods
to accomplish the administration are known to those of ordinary
skill in the art. The administration may, for example, be
intravenous, intraperitoneal, intramuscular, intracavity,
subcutaneous or transdermal. It may also be possible to obtain
compositions which may be topically or orally administered, or
which may be capable of transmission across mucous membranes.
[0103] Solutions or suspensions used for intradermal or
subcutaneous application typically include one or more of the
following components: a sterile diluent such as water for
injection, saline solution, fixed oils, polyethylene glycols,
glycerin, propylene glycol, or other synthetic solvents;
antibacterial agents such as benzyl alcohol or methyl parabens;
antioxidants such as ascorbic acid or sodium bisulfite; chelating
agents such as ethylenediaminetetraacetic acid; buffers such as
acetates, citrates or phosphates; and agents for the adjustment of
tonicity such as sodium chloride or dextrose. The pH can be
adjusted with acids or bases, such as hydrochloric acid or sodium
hydroxide. Such preparations may be enclosed in ampoules,
disposable syringes or multiple dose vials made of glass or
plastic.
[0104] Pharmaceutical compositions suitable for injection include
sterile aqueous solutions or dispersions and sterile powders for
the extemporaneous preparation of sterile injectable solutions or
dispersion. For intravenous administration, suitable carriers
include physiological saline, bacteriostatic water, Cremophor EL
(BASF, Parsippany, N.J.) or phosphate buffered saline (PBS). In all
cases, the composition must be sterile and should be fluid to the
extent that easy syringability exists. It should be stable under
the conditions of manufacture and storage and must be preserved
against the contaminating action of microorganisms such as bacteria
and fungi. Prevention of the action of microorganisms can be
achieved by various antibacterial and antifungal agents, for
example, parabens, chlorobutanol, phenol, ascorbic acid,
thimerosal, and the like. In many cases, it will be preferable to
include isotonic agents, for example, sugars; polyalcohols such as
mannitol, sorbitol, and sodium chloride in the composition. The
carrier can be a solvent or dispersion medium containing, for
example, water, ethanol, polyol (for example, glycerol, propylene
glycol, and liquid polyetheylene glycol, and the like), and
suitable mixtures thereof. The proper fluidity can be maintained,
for example, by the use of a coating such as lecithin, by the
maintenance of the required particle size in the case of dispersion
and/or by the use of surfactants. Prolonged absorption of the
injectable compositions can be brought about by including in the
composition an agent which delays absorption, for example, aluminum
monostearate, and gelatin.
[0105] Oral compositions generally include an inert diluent or an
edible carrier. They can be enclosed in gelatin capsules or
compressed into tablets. For oral administration, the antibodies
can be combined with excipients and used in the form of tablets,
troches, or capsules. Pharmaceutically compatible binding agents,
and/or adjuvant materials can be included as part of the
composition. The tablets, pills, capsules, troches, and the like
can contain any of the following ingredients, or compounds of a
similar nature; a binder such as microcrystalline cellulose, gum
tragacanth or gelatin; an excipient such as starch or lactose, a
disintegrating agent such as alginic acid, Primogel, or corn
starch; a lubricant such as magnesium stearate or Sterotes; a
glidant such as colloidal silicon dioxide; a sweetening agent such
as sucrose or saccharin; or a flavoring agent such as peppermint,
methyl salicylate, or orange flavoring.
[0106] Systemic administration can also be by transmucosal or
transdermal means. For transmucosal or transdermal administration,
penetrants appropriate to the barrier to be permeated are used in
the formulation. Such penetrants are generally known in the art,
and include, for example, detergents, bile salts, and fusidic acid
derivatives. Transmucosal administration may be accomplished, for
example, through the use of lozenges, nasal sprays, inhalers, or
suppositories; For example, in case of antibodies that comprise the
Fc portion, compositions may be capable of transmission across
mucous membranes in intestine, mouth, or lungs (e.g., via the FcRn
receptor-mediated pathway as described in U.S. Pat. No. 6,030,613).
For transdermal administration, the active compounds may be
formulated into ointments, salves, gels, or creams as generally
known in the art. For administration by inhalation, the antibodies
may be delivered in the form of an aerosol spray from pressured
container or dispenser, which contains a suitable propellant, e.g.,
a gas such as carbon dioxide, or a nebulizer.
[0107] In certain embodiments, the presently disclosed antibodies
are prepared with carriers that will protect the compound against
rapid elimination from the body, such as a controlled release
formulation, including implants and microencapsulated delivery
systems. Biodegradable, biocompatible polymers can be used, such as
ethylene vinyl acetate, polyanhydrides, polyglycolic acid,
collagen, polyorthoesters, and polylactic acid. Methods for
preparation of such formulations will be apparent to those skilled
in the art. Liposomal suspensions containing the presently
disclosed antibodies can also be used as pharmaceutically
acceptable carriers. These can be prepared according to methods
known to those skilled in the art, for example, as described in
U.S. Pat. No. 4,522,811.
[0108] It may be advantageous to formulate oral or parenteral
compositions in a dosage unit form for ease of administration and
uniformity of dosage. The term "dosage unit form" as used herein
refers to physically discrete units suited as unitary dosages for
the subject to be treated; each unit containing a predetermined
quantity of active compound calculated to produce the desired
therapeutic effect in association with the required pharmaceutical
carrier.
[0109] Toxicity and therapeutic efficacy of the composition of the
invention can be determined by standard pharmaceutical procedures
in cell cultures or experimental animals, e.g., for determining the
LD.sub.50 (the dose lethal to 50% of the population) and the
ED.sub.50 (the dose therapeutically effective in 50% of the
population). The dose ratio between toxic and therapeutic effects
is the therapeutic index and it can be expressed as the ratio
LD.sub.50/ED.sub.50. Compositions that exhibit large therapeutic
indices are preferred.
[0110] For any composition used in the present invention, the
therapeutically effective dose can be estimated initially from cell
culture assays. Examples of suitable bioassays include DNA
replication assays, cytokine release assays, transcription-based
assays, PD-1/PD-L1 binding assays, creatine kinase assays, assays
based on the differentiation of pre-adipocytes, assays based on
glucose uptake in adipocytes, immunological assays other assays as,
for example, described in the Examples. The data obtained from the
cell culture assays and animal studies can be used in formulating a
range of dosage for use in humans. A dose may be formulated in
animal models to achieve a circulating plasma concentration range
that includes the IC.sub.50 (i.e., the concentration of the
antibody which achieves a half-maximal inhibition of symptoms).
Circulating levels in plasma may be measured, for example, by high
performance liquid chromatography. The effects of any particular
dosage can be monitored by a suitable bioassay. The dosage lies
preferably within a range of circulating concentrations with little
or no toxicity. The dosage may vary depending upon the dosage form
employed and the route of administration utilized.
[0111] The following Examples do not in any way limit the scope of
the invention. One of ordinary skill in the art will recognize the
numerous modifications and variations that may be performed without
altering the spirit or scope of the present invention. Such
modifications and variations are encompassed within the scope of
the invention. The entire contents of all references, patents, and
published patent applications cited throughout this application are
herein incorporated by reference.
EXAMPLES
Example 1
Selection of PD-1 Binding ScFv's
[0112] An scFv phagemid library, which is an expanded version of
the 1.38.times.10.sup.10 library described by Vaughan et al.
(Nature Biotech. (1996) 14: 309-314) was used to select antibodies
specific for human PD-1. Soluble PD-1 fusion protein (at 20
.mu.g/ml in phosphate buffered saline (PBS)) or control fusion
protein (at 50 .mu.g/ml in PBS) was coated onto wells of a
microtiter plate overnight at 4.degree. C. Wells were washed in PBS
and blocked for 1 hour at 37.degree. C. in MPBS (3% milk powder in
PBS). Purified phage (10.sup.12 transducing units (tu)) was blocked
for 1 hour in a final volume of 100 .mu.l of 3% MPBS. Blocked phage
was added to blocked control fusion protein wells and incubated for
1 hour. The blocked and deselected phage were then transferred to
the blocked wells coated with the PD-1 fusion protein and were
incubated for an additional hour. Wells were washed 5 times with
PBST (PBS containing 0.1% v/v Tween 20), then 5 times with PBS.
Bound phage particles were eluted and used to infect 10 ml
exponentially growing E. coli TG1. Infected cells were grown in 2TY
broth for 1 hour at 37.degree. C., then spread onto 2TYAG plates
and incubated overnight at 30.degree. C. Colonies were scraped off
the plates into 10 ml 2TY broth and 15% glycerol added for storage
at -70.degree. C.
[0113] Glycerol stock cultures from the first round of panning
selection were superinfected with helper phage and rescued to give
scFv antibody-expressing phage particles for the second round of
panning. A total of two rounds of panning were carried out in this
way for isolation of PD1-17, except in the second round of panning
20 .mu.g/ml of control protein were used for deselection. Clones
PD1-28, PD1-33, and PD1-35 were selected following three rounds of
selection. Deselection in the second and third rounds was carried
out using 10 .mu.g/ml control fusion protein.
[0114] Antibodies to murine PD-1 were selected by soluble selection
using biotinylated murine PD-1 fusion protein at a final
concentration of 100 nM. An scFv phagemid library, as described
above, was used. Purified scFv phage (10.sup.12 tu) in 1 ml 3% MPBS
were blocked for 30 minutes, then biotinylated antigen was added
and incubated at room temperature for 1 hour. Phage/antigen was
added to 250 .mu.l of Dynal M280 Streptavidin magnetic beads that
had been blocked for 1 hour at 37.degree. C. in 1 ml of 3% MPBS and
incubated for a further 15 minutes at room temperature. Beads were
captured using a magnetic rack and washed 4 times in 1 ml of 3%
MPBS/0.1% (v/v) Tween 20 followed by 3 washes in PBS. After the
last PBS wash, beads were resuspended in 100 .mu.l PBS and used to
infect 5 ml exponentially growing E. coli TG-1 cells. Infected
cells were incubated for 1 hour at 37.degree. C. (30 minutes
stationary, 30 minutes shaking at 250 rpm), then spread on 2TYAG
plates and incubated overnight at 30.degree. C. Output colonies
were scraped off the plates and phage rescued as described above. A
second round of soluble selection was carried out as described
above.
Example 2
Specificity of Antibodies for PD-1 by a Phage ELISA
[0115] To determine the specificity of antibodies for PD-1, a phage
ELISA was performed against PD-1 fusion protein and control
proteins. Individual E. coli colonies from selection outputs were
picked into 96 well plates containing 100 .mu.l of 2TYAG medium per
well. M13K07 helper phage was added to a multiplicity of infection
(moi) of 10 to the exponentially growing culture and the plates
incubated an additional 1 hour at 37.degree. C. Plates were
centrifuged in a benchtop centrifuge at 2000 rpm for 10 minutes.
The supernatant was removed and cell pellets were resuspended in
100 .mu.l 2TYAK and incubated at 30.degree. C. overnight with
shaking. The next day, plates were centrifuged at 2000 rpm for 10
minutes and phage-containing supernatant from each well was
transferred to a fresh 96 well plate. Phage samples were blocked in
a final concentration of 3% MPBS prior to ELISA.
[0116] Human or mouse PD-1 fusion protein and control fusion and
non-fusion proteins were coated overnight at 4.degree. C. onto
96-well microtiter plates at 0.5-2.5 .mu.g/ml in PBS. After
coating, the solutions were removed from the wells, and the plates
blocked for 1 hour in 3% MPBS. Plates were rinsed with PBS and then
50 .mu.l of pre-blocked phage were added to each well. The plates
were incubated for 1 hour and then washed 3 times with PBST
followed by 3 washes with PBS. To each well, 50 .mu.l of a 1:5000
dilution of anti-M13-HRP conjugate (Pharmacia, Peapack, N.J.) was
added, and the plates incubated for 40-60 minutes. Each plate was
washed three times with PBST then 3 times with PBS. Fifty .mu.l of
TMB substrate was added to each well, and the samples were
incubated until color development. The reaction was stopped by the
addition of 25 .mu.l of 0.5 M H.sub.2SO.sub.4. The signal generated
was measured by reading the absorbance at 450 nm using a microtiter
plate reader. Clones showing specific binding to PD-1 fusion
protein but not to control fusion proteins were thus identified and
confirmed.
[0117] Specificity data for the PD1-17 scFv is shown in FIG. 1A.
Reactivity of PD1-28, PD1-33, and PD1-35 scFv's with human PD-1 is
shown in FIG. 1B (an IgG.sub.1 control did not bind PD-1).
Example 3
Identification of Antibody Clones
[0118] PD-1-binding scFv E. coli clones were streaked out onto
2TYAG plates and incubated overnight at 30.degree. C. Colonies from
these plates were sequenced using pCANTAB6 vector sequence oligos
to amplify the V.sub.H and V.sub.L regions from the scFv clone.
Unique PD-1 binding clones were assayed for neutralization: of
PD-L1 binding to PD-1 as described in Example 4. Sequence
differences between scFv and IgG formats are due to changes
introduced by PCR primers during the conversion from scFv to
IgG.
Example 4
Biochemical Binding Inhibition Assay and Screen
[0119] ScFv production was induced by addition of 1 mM IPTG to
exponentially growing cultures and incubation overnight at
30.degree. C. Crude scFv-containing periplasmic extracts were
obtained by subjecting the bacterial pellets from the overnight
induction to osmotic shock. Pellets were resuspended in 20% (w/v)
sucrose, 50 mM Tris-HCl, pH 7.5, 1 mM EDTA and cooled on ice for 30
minutes. Cellular debris was removed by centrifugation, and the
scFv was purified by chromatography and buffer-exchanged into PBS.
Purified scFv's (PD1-17, PD1-28, PD1-33, and PD1-35) were tested
for the ability to inhibit the binding of biotinylated human PD-L1
fusion protein to human PD-1 fusion protein immobilized on plastic
in a 96 well microtiter plate assay. Binding of biotinylated PD-L1
fusion protein was detected with AMDEX-alkaline phosphatase, and
the signal generated was measured by reading the absorbance at 405
nm using a microtiter plate reader. Data was expressed as a
percentage of the total binding and a titration of scFv
concentrations was tested to establish clone potency as calculated
IC.sub.50 values. Clone potency data for the scFv and IgG
antibodies is shown in Table 5.
[0120] PD1-F2 scFv was produced and purified as described above.
Cells expressing murine PD-1 were added at 10.sup.5 cells/well in a
final volume of 100 .mu.l to a poly-D-lysine-coated 96 well
microtiter plate. Cells were centrifuged and washed twice in PBS,
then blocked with 300 .mu.l 1% BSA in PBS for 1 hour at room
temperature. Blocked cells were washed three times in PBST, prior
to addition of 25 .mu.l/well of assay buffer (0.05% BSA, 0.05%
Tween 20 in Dulbecco's PBS) or sample, followed by 25 .mu.l of
biotinylated murine PD-L1 fusion protein at 300 ng/ml. Binding of
biotinylated PD-L1 fusion protein was detected with Amdex alkaline
phosphatase and signals read as described above. Potencies of
PD1-F2 scFv and IgG are shown in Table 6.
TABLE-US-00006 TABLE 6 Potency of Anti-PD-1 ScFv and IgG Antibodies
Clone ScFv IC.sub.50 (nM) IgG IC.sub.50 (nM) PD1-17 726 2.5 PD1-28
560 1.4 PD1-33 74 1.8 PD1-35 85 2.3 PD1-F2 28 1.0
Example 5
Conversion of ScFv to IgG
[0121] Heavy and light chain V regions from scFv clones were
amplified by PCR using clone-specific primers. PCR products were
digested with appropriate restriction enzymes and subcloned into
vectors containing human IgG.sub.1 heavy chain constant domain
(Takahashi et al. (1982) Cell 29, 671) or vectors containing human
lambda or kappa light chain constant domains (Hieter et al. (1982)
Nature 294, 536). Based on the germlines of the V.sub.H and V.sub.L
segments, it was determined whether kappa or lambda light chain
constant domains were used for conversion (Table 7).
TABLE-US-00007 TABLE 7 Germlines of V.sub.H and V.sub.L Regions of
PD-1 Antibody Clones Clone V.sub.H germline V.sub.L germline PD1-17
DP-70 DPL-8 PD1-28 DP-14 DPL-23 PD1-33 DP-7 DPL-11 PD1-35 DP-65
DPL-2 PD1-F2 DP-47 L12 (.kappa.)
[0122] The insertion of V region domains into plasmids was verified
by sequencing of plasmid DNA from individual E. coli colonies.
Plasmids were prepared from E. coli cultures by standard techniques
and heavy and light chain constructs cotransfected into eukaryotic
cells using standard techniques. Secreted IgG was purified using
Protein A Sepharose (Pharmacia) and buffer-exchanged into PBS.
[0123] The binding affinity of the anti-mouse PD1 antibody PD1-F2
was determined with a Surface Plasmon Resonance (SPR) system
(BIAcore 3000) (Biacore, Piscataway, N.J.) using murine PD-1 fusion
immobilized on a CM5 sensor chip. The concentration of PD1-F2 in
the flow cell ranged from 7.81 to 125 nM, while the concentration
of the anti-mouse PD1 antibody J43 (eBioscience, San Diego, Calif.)
ranged from 25 nM to 500 nM. The equilibrium constant K.sub.D for
PD1-F2 is 6.7.times.10.sup.-9 M (K.sub.A=1.5.times.10.sup.8
M.sup.-1), whereas K.sub.D for J43 is 3.8.times.10.sup.-7 M
(K.sub.A=2.6.times.10.sup.6 M.sup.-1).
[0124] The ability of anti-PD-1 IgG's to bind human or murine PD-1
was determined as follows. ELISA plates were incubated with 2.5
.mu.g/ml human PD-1/IgG chimera overnight. Plates were washed with
PBS/1% BSA and incubated with serial dilutions of a test antibody
for 2 hours at room temperature (RT). After washing, saturating
concentrations of HRP-conjugated goat anti-human antibody or
HRP-conjugated rabbit anti-murine antibody were added, and the
samples were incubated for 1 hour at RT. Unbound goat and rabbit
antibodies were washed using PBS/1% BSA. The assay was developed
using TBM. Results were expressed as OD 405 absorbency values and
are presented in FIGS. 2A-2C. Murine anti-human PD-1 antibody J110
is commercially available (eBioscience, San Diego, Calif.) and was
included for comparison.
Example 6
Selected PD-1 Antibodies Inhibit Binding of PD-L1 to PD-1
[0125] Inhibition assays were performed to assess the ability of
the antibodies to block binding of PD-L1 to PD-1. ELISA was
performed as described in Example 2 with modifications. After
incubation with a primary, anti-PD-1 antibody for 2 hours at RT, a
fixed concentration (1 .mu.g/ml) of biotin-conjugated PD-L1-Ig was
added, and the samples were further incubated for 1 hour at RT.
After washing, saturating concentrations of avidin-HRP were added,
and incubated for 1 hour at RT. Unbound avidin-HRP was washed using
PBS/1% BSA. The assay was developed using TMB.
[0126] Results were compared to those obtained with J110 as shown
in FIG. 3. Anti-human PD-1 antibodies J110 and PD1-30 did not
inhibit the binding of PD-L1 to PD-1. Anti-human antibodies PD1-17,
PD1-28, PD1-33, and PD1-35 and anti-mouse antibody PD1-F2 block
PD-1/PD-L1 interaction.
Example 7
PD-1 Antibodies Recognize Distinct Sites on PD-1
[0127] Inhibition assays were performed to map sites recognize by
the various human anti-human PD-1 antibodies. ELISA was performed
as described in Example 6 with minor modifications. After
incubation with primary antibody for 2 hours at RT, a fixed
concentration (0.25 .mu.g/ml) of biotin-conjugated anti-PD-1
antibody J110 was added, and the samples were further incubated for
1 hour at RT. After washing, saturating concentrations of
avidin-HRP were added, and incubated for 1 hour at Rt. Unbound
avidin-HRP was washed using PBS/1% BSA. The assay was developed
using TMB.
[0128] As shown in FIG. 4, binding of anti-human PD-1 antibodies
(J110, J116, PD1-17, PD1-28, PD1-33, and PD1-35) defines at least
two distinct sites on PD-1. Cross-blocking results show that J110
and J116, bind to identical or overlapping sites while PD1-17, 28,
33, and 35 bind to another distinct site. Binding of J116 or J110
to PD-1 blocks the binding of J110. In contrast, binding of PD1-17,
PD1-28, PD1-33, and PD1-35 do not block binding of J110. This
suggests that the tested anti-PD-1 antibodies bind to at least two
distinct epitopes: one recognized by J110 and J116, and the other
one recognized by PD1-17, PD1-28, PD1-33, and PD1-35.
Example 8
PD-1 Engagement Results in Decreased T Cell Responses
[0129] CD4+ T cells (5.times.10.sup.4 cells/well) were stimulated
with tosyl-beads (Dynal, Great Neck, N.Y.) coated with
anti-hCD3+/-PD-L1-Fc or anti-PD-1 (PD1-17 or J110). Concentration
of fusion protein or antibody titer was as indicated in the X-axis
of FIG. 5. After 72 hours, proliferation was determined by
.sup.3H-thymidine incorporation. Incorporated radioactivity was
determined using a LKB 1205 plate reader.
[0130] As shown in FIG. 5, PD-1 engagement by anti-PD-1 antibody
PD1-17 or PD-L1.Fc caused a decrease in T cell proliferation. Thus,
PD1-17 can mimic PD-1 ligands and delivered an inhibitory signal.
As discussed below (Example 9), this inhibitory signal results in
decreased T cell proliferation and IL-2 production. Antibodies
PD1-28, PD1-33, and PD1-35 have the same effect as PD1-17. The
effect is dose-dependent, as activation of cells in the presence of
increasing concentrations of PD1-17 or PD-L1.Fc results in
decreased T cell proliferation. The control anti-PD-1 antibodies,
J110 (FIG. 5) or J116 (data not shown), do not inhibit T cell
responses and increasing the concentration of J110 has minimal
effect on T cell proliferation. For comparison, values are
represented as percentage of the anti-CD3 response. "100%"
represents CPMs obtained when cells were activated with
anti-CD3/murine IgG-coated microspheres. Altogether these results
indicate that some but not all antibodies that recognize PD-1 can
act as agonists of the PD-1 pathway.
[0131] Further experiments were performed to address whether PD-1
downregulation of T cell responses required coordinate TcR/PD-1
engagement on a single (CIS) or a separate (TRANS) cell surfaces.
Two sets of microspheres were prepared: one set contained anti-CD3
and PD-L1.Fc (CIS), the other set contained anti-CD3 or PD-L1.Fc
(TRANS). Inhibition through PD-1 was only observed under conditions
where both PD-1 and TcR were engaged by ligands on the same surface
(CIS). At all bead:cell ratios tested, no inhibition was observed
in conditions where TCR and PD-1 signals were delivered on separate
surfaces (TRANS).
[0132] To rule out steric hindrance in the TRANS experiments,
similar assays were set up using anti-CD3 antibody and B7.2.Fc. In
these assays, B7 costimulation of T cell responses was observed in
both CIS and TRANS conditions. Altogether, these findings
demonstrate that PD-1 proximity to TCR is required for the receptor
modulatory function on T cell activation. Therefore, to modulate a
T cell response, both activating and inhibitory signals must
emanate from the same surface whether the surface is that of a cell
or a bead.
Example 9
Blockage of PD-1 Engagement by Antibody Results in Enhanced
Proliferation
[0133] For assessing effect of soluble anti-PD-1 antibody on
proliferation, CD4+ T cells were pre-activated for 48 hours with
anti-CD3/anti-CD28-coated beads, harvested, and restimulated with
the indicated concentration of PHA plus 10 ng/ml IL-2 in the
presence of PD1-17, J110, or control IgG. Each of the antibodies
was added at various concentrations at initiation of the culture.
Proliferation was measured at 72 hr.
[0134] The results demonstrate that PD1-17 (FIG. 6) and PD1-35
(data not shown) enhanced proliferation of primary T cells. The
control antibody J110 did not enhance in vitro T cell responses.
Selected anti-PD1 antibodies, as exemplified by PD1-17 and PD-35,
inhibit the interaction of PD-1 with its natural ligands and
thereby block delivery of a negative signal. The blockade of the
negative signal also results in enhanced proliferation and IL-2
production.
Example 10
Treatment of Disorders
[0135] Modulation of immune response regulated by PD-1 is useful in
instances where an immunosuppressive effect or augmentation of
immune response is desired. This example describes the use of PD-1
antibodies as PD-1 agonists or antagonists to treat a subject at
disease onset or having an established immune disorder or cancer,
respectively.
[0136] Subjects at risk for or afflicted with cancer may be in need
of immune response augmentation would benefit from treatment with a
PD-1 antagonist, such as an anti-PD-1 antibody of the present
invention in a soluble form. Most commonly, antibodies are
administered in an outpatient setting by weekly administration at
about 0.1-10 mg/kg dose by slow intravenous (IV) infusion. The
appropriate therapeutically effective dose of an antagonist is
selected by a treating clinician and would range approximately from
1 .mu.g/kg to 20 mg/kg, from 1 .mu.g/kg to 10 mg/kg, from 1
.mu.g/kg to 1 mg/kg, from 10 .mu.g/kg to 1 mg/kg, from 10 .mu.g/kg
to 100 .mu.g/kg, from 100 .mu.g to 1 mg/kg, and from 500 .mu.g/kg
to 5 mg/kg.
[0137] The antibodies are also used to prevent and/or to reduce
severity and/or symptoms of diseases or conditions that involve an
aberrant or undesirable immune response, such as in autoimmune
disorders exemplified below.
[0138] Multiple sclerosis (MS) is a central nervous system disease
that is characterized by inflammation and loss of myelin sheaths.
In the experimental autoimmune encephalitis (EAE) mouse model for
multiple sclerosis (Tuohy et al. (J. Immunol. (1988) 141:
1126-1130), Sobel et al. (J. Immunol. (1984) 132: 2393-2401), and
Traugott (Cell Immunol. (1989) 119: 114-129), treatment of mice
with a PD-1 agonist prior (and continuously) to EAE induction is
expected to prevent or delay the onset of MS.
[0139] Arthritis is a disease characterized by inflammation in the
joints. In the collagen induced arthritis (CIA) mouse model for
rheumatoid arthritis (Courtenay et al. (Nature (1980) 283: 666-628)
and Williams et al. (Immunol. (1995) 84: 433-439)), treatment with
a PD-1 agonist is expected to prevent or treat rheumatoid arthritis
(RA) or other arthritic diseases.
[0140] Systemic Lupus Erythematosis (SLE) is an autoimmune disease
characterized by the presence of autoantibodies. The antibodies and
compositions of this invention can be used as PD-1 agonists to
inhibit activities of autoreactive T cells and B cells, and prevent
or treat SLE or related diseases in NZB.times.NZW mice (a mouse
model for SLE) (Immunologic Defects in Laboratory Animals, Gershwin
et al. eds., Plenum Press, 1981) or in humans.
[0141] It is anticipated that PD-1 antibodies of the invention
would be administered as PD-1 agonists in ex vivo therapy with a
frequency of one per month or less. Treatment duration could range
between one month and several years.
[0142] To test the clinical efficacy of antibodies in humans,
individuals with melanoma, prostate cancer, RA, SLE, MS, type I
diabetes, are identified and randomized to a treatment group.
Treatment groups include a placebo group and one to three groups
treated with a PD-1 agonist (different doses). Individuals are
followed prospectively for one to three years. It is anticipated
that individuals receiving treatment would exhibit an
improvement.
[0143] The specification is most thoroughly understood in light of
the teachings of the references cited within the specification, all
of which are hereby incorporated by reference in their entirety.
The embodiments within the specification provide an illustration of
embodiments of the invention and should not be construed to limit
the scope of the invention. The skilled artisan recognizes that
many other embodiments are encompassed by the claimed invention and
that it is intended that the specification and examples be
considered as exemplary only, with a true scope and spirit of the
invention being indicated by the following claims.
Sequence CWU 1
1
581384DNAHomo sapiens 1caggtgcagc tgcaggagtc gggcccagga gtggtgaagc
cttcggggac cctgtccctc 60acctgcgcta tttctggtgg ctccatcggc tctggtggct
ccatcagaag tactaggtgg 120tggagttggg tccgccagtc cccagggaag
gggctggagt ggataggcga aatctatcat 180agtgggagca ccaactacaa
cccgtccctc aagagtcgcg tcaccatatc actagacaag 240tctaggaatc
acttctccct gaggctgaac tctgtgaccg ccgcggacac ggccgtttat
300tactgtgcga gacaggacta cggtgactcc ggcgactggt acttcgatct
gtggggcaag 360gggacaatgg tcaccgtctc ctca 3842128PRTHomo sapiens
2Gln Val Gln Leu Gln Glu Ser Gly Pro Gly Val Val Lys Pro Ser Gly1 5
10 15Thr Leu Ser Leu Thr Cys Ala Ile Ser Gly Gly Ser Ile Gly Ser
Gly 20 25 30Gly Ser Ile Arg Ser Thr Arg Trp Trp Ser Trp Val Arg Gln
Ser Pro 35 40 45Gly Lys Gly Leu Glu Trp Ile Gly Glu Ile Tyr His Ser
Gly Ser Thr 50 55 60Asn Tyr Asn Pro Ser Leu Lys Ser Arg Val Thr Ile
Ser Leu Asp Lys65 70 75 80Ser Arg Asn His Phe Ser Leu Arg Leu Asn
Ser Val Thr Ala Ala Asp 85 90 95Thr Ala Val Tyr Tyr Cys Ala Arg Gln
Asp Tyr Gly Asp Ser Gly Asp 100 105 110Trp Tyr Phe Asp Leu Trp Gly
Lys Gly Thr Met Val Thr Val Ser Ser 115 120 1253330DNAHomo sapiens
3aattttatgc tgactcagcc ccactctgtg tcggagtctc cggggaagac ggtaaccatc
60tcctgcaccc gcagcagtgg cagcattgcc agcaactctg tgcagtggta ccagcagcgc
120ccgggcagtt cccccaccac tgtgatctat gaggataacc aaagaccctc
tggggtccct 180gatcggttct ctggctccat cgacagctcc tccaactctg
cctccctcac cgtctctgga 240ctgaagactg aggacgaggc tgactactac
tgtcagtctt ctgatagcag cgctgtggta 300ttcggcagtg ggaccaagct
gaccgtccta 3304110PRTHomo sapiens 4Asn Phe Met Leu Thr Gln Pro His
Ser Val Ser Glu Ser Pro Gly Lys1 5 10 15Thr Val Thr Ile Ser Cys Thr
Arg Ser Ser Gly Ser Ile Ala Ser Asn 20 25 30Ser Val Gln Trp Tyr Gln
Gln Arg Pro Gly Ser Ser Pro Thr Thr Val 35 40 45Ile Tyr Glu Asp Asn
Gln Arg Pro Ser Gly Val Pro Asp Arg Phe Ser 50 55 60Gly Ser Ile Asp
Ser Ser Ser Asn Ser Ala Ser Leu Thr Val Ser Gly65 70 75 80Leu Lys
Thr Glu Asp Glu Ala Asp Tyr Tyr Cys Gln Ser Ser Asp Ser 85 90 95Ser
Ala Val Val Phe Gly Ser Gly Thr Lys Leu Thr Val Leu 100 105
1105357DNAHomo sapiens 5gaggtgcagc tggtgcagtc tggagctgag gtgaagaagc
ctggggcctc agtgaaagtc 60tcctgcaagg cttctggtta cagatttacc agctacggca
tcagctgggt gcgacaggcc 120cctggacaag ggcttgagtg gatgggatgg
atcagcgctt acaatggtaa cacaaactac 180gcacagaagc tccagggcag
agtcaccatg accacagaca catccacgaa cacagcctac 240atggagctga
ggagcctgag atctgacgac acggccgtgt attactgtgc gagagacgcg
300gattatagta gtgggtctgg gtactggggc cagggaaccc tggtcaccgt ctcctca
3576119PRTHomo sapiens 6Glu Val Gln Leu Val Gln Ser Gly Ala Glu Val
Lys Lys Pro Gly Ala1 5 10 15Ser Val Lys Val Ser Cys Lys Ala Ser Gly
Tyr Arg Phe Thr Ser Tyr 20 25 30Gly Ile Ser Trp Val Arg Gln Ala Pro
Gly Gln Gly Leu Glu Trp Met 35 40 45Gly Trp Ile Ser Ala Tyr Asn Gly
Asn Thr Asn Tyr Ala Gln Lys Leu 50 55 60Gln Gly Arg Val Thr Met Thr
Thr Asp Thr Ser Thr Asn Thr Ala Tyr65 70 75 80Met Glu Leu Arg Ser
Leu Arg Ser Asp Asp Thr Ala Val Tyr Tyr Cys 85 90 95Ala Arg Asp Ala
Asp Tyr Ser Ser Gly Ser Gly Tyr Trp Gly Gln Gly 100 105 110Thr Leu
Val Thr Val Ser Ser 1157324DNAHomo sapiens 7tcctatgagc tgactcagcc
accctcggtg tcagtgtccc caggacagac ggccaggatc 60acctgttctg gagatgcatt
gccaaagcaa tatgcttatt ggtaccagca gaagccaggc 120caggcccctg
tgatggttat atataaagac actgagaggc cctcagggat ccctgagcga
180ttctctggct ccagctcagg gacaaaagtc acgttgacca tcagtggagt
ccaggcagaa 240gacgaggctg actattattg tcaatcagca gacaacagta
ttacttatag ggtgttcggc 300ggagggacca aggtcaccgt ccta 3248108PRTHomo
sapiens 8Ser Tyr Glu Leu Thr Gln Pro Pro Ser Val Ser Val Ser Pro
Gly Gln1 5 10 15Thr Ala Arg Ile Thr Cys Ser Gly Asp Ala Leu Pro Lys
Gln Tyr Ala 20 25 30Tyr Trp Tyr Gln Gln Lys Pro Gly Gln Ala Pro Val
Met Val Ile Tyr 35 40 45Lys Asp Thr Glu Arg Pro Ser Gly Ile Pro Glu
Arg Phe Ser Gly Ser 50 55 60Ser Ser Gly Thr Lys Val Thr Leu Thr Ile
Ser Gly Val Gln Ala Glu65 70 75 80Asp Glu Ala Asp Tyr Tyr Cys Gln
Ser Ala Asp Asn Ser Ile Thr Tyr 85 90 95Arg Val Phe Gly Gly Gly Thr
Lys Val Thr Val Leu 100 1059357DNAHomo sapiens 9caggtgcagc
tggtgcaatc tggggctgag gtgaagaaac ctggggcctc agtgagggtt 60tcctgcaagg
catctggata caccctcacc agttactata ttcactgggt gcgacaggcc
120cctggacaag ggcttgagtg gatgggaata atcaacccta gaggtgccac
cataagctac 180gcacagaagt tccagggcag agtcaccatg accagggaca
cgtccacgag tacagtctac 240atggaactga gaaacttgaa atctgaggac
acggccctgt attactgtgc tactgcaggc 300atctatggtt ttgactttga
ctactggggc agaggaaccc tggtcaccgt ctcctca 35710119PRTHomo sapiens
10Gln Val Gln Leu Val Gln Ser Gly Ala Glu Val Lys Lys Pro Gly Ala1
5 10 15Ser Val Arg Val Ser Cys Lys Ala Ser Gly Tyr Thr Leu Thr Ser
Tyr 20 25 30Tyr Ile His Trp Val Arg Gln Ala Pro Gly Gln Gly Leu Glu
Trp Met 35 40 45Gly Ile Ile Asn Pro Arg Gly Ala Thr Ile Ser Tyr Ala
Gln Lys Phe 50 55 60Gln Gly Arg Val Thr Met Thr Arg Asp Thr Ser Thr
Ser Thr Val Tyr65 70 75 80Met Glu Leu Arg Asn Leu Lys Ser Glu Asp
Thr Ala Leu Tyr Tyr Cys 85 90 95Ala Thr Ala Gly Ile Tyr Gly Phe Asp
Phe Asp Tyr Trp Gly Arg Gly 100 105 110Thr Leu Val Thr Val Ser Ser
11511333DNAHomo sapiens 11cagtctgccc tgactcagcc tgcctccgtg
tctgggtctc ctgggcagtc gatcaccatc 60tcctgcactg gaaccagtaa tgacgttggt
ggttataatt atgtctcctg gtaccaacat 120cacccaggca aagcccccaa
actcatcatt tatgatgtca ctaaccggcc ctcaggggtt 180tctgatcgct
tctctggctc caagtctggc aacacggcct ccctgaccat ctctgggctc
240ctggctgagg acgagggtga ttattactgc agctcataca caattgttac
caatttcgag 300gttcttttcg gcggagggac caagctgacc gtc 33312111PRTHomo
sapiens 12Gln Ser Ala Leu Thr Gln Pro Ala Ser Val Ser Gly Ser Pro
Gly Gln1 5 10 15Ser Ile Thr Ile Ser Cys Thr Gly Thr Ser Asn Asp Val
Gly Gly Tyr 20 25 30Asn Tyr Val Ser Trp Tyr Gln His His Pro Gly Lys
Ala Pro Lys Leu 35 40 45Ile Ile Tyr Asp Val Thr Asn Arg Pro Ser Gly
Val Ser Asp Arg Phe 50 55 60Ser Gly Ser Lys Ser Gly Asn Thr Ala Ser
Leu Thr Ile Ser Gly Leu65 70 75 80Leu Ala Glu Asp Glu Gly Asp Tyr
Tyr Cys Ser Ser Tyr Thr Ile Val 85 90 95Thr Asn Phe Glu Val Leu Phe
Gly Gly Gly Thr Lys Leu Thr Val 100 105 11013381DNAHomo sapiens
13caggtgcagc tgcaggagtc gggcccagga ctggtgaagc cttcacagac cctgtccctc
60acctgcactg tctctggtgg ctccatcagc agtggtgctt attactggag ctggatccgc
120cagcacccag ggaagggcct ggagtggatt gggtacatct attacaatgg
gaacacgtac 180tacaacccgt ccctcaggag tctagttacc atatcagtag
acgcgtctaa gaaccagttc 240tccctgaagc tgagctctgt gactgccgcg
gacacggccg tctattactg tgcgagagcg 300tctgattacg tttggggggg
ttatcgttat atggatgctt ttgatatctg gggccgggga 360accctggtca
ccgtctcctc a 38114127PRTHomo sapiens 14Gln Val Gln Leu Gln Glu Ser
Gly Pro Gly Leu Val Lys Pro Ser Gln1 5 10 15Thr Leu Ser Leu Thr Cys
Thr Val Ser Gly Gly Ser Ile Ser Ser Gly 20 25 30Ala Tyr Tyr Trp Ser
Trp Ile Arg Gln His Pro Gly Lys Gly Leu Glu 35 40 45Trp Ile Gly Tyr
Ile Tyr Tyr Asn Gly Asn Thr Tyr Tyr Asn Pro Ser 50 55 60Leu Arg Ser
Leu Val Thr Ile Ser Val Asp Ala Ser Lys Asn Gln Phe65 70 75 80Ser
Leu Lys Leu Ser Ser Val Thr Ala Ala Asp Thr Ala Val Tyr Tyr 85 90
95Cys Ala Arg Ala Ser Asp Tyr Val Trp Gly Gly Tyr Arg Tyr Met Asp
100 105 110Ala Phe Asp Ile Trp Gly Arg Gly Thr Leu Ile Thr Val Ser
Ser 115 120 12515336DNAHomo sapiens 15cagtctgtgc tgactcagcc
accctcagcg tctgggaccc ccgggcagag ggtcaccatc 60tcttgttctg gaagcaactc
caacatcgga agtaattctg taaactggta ccagcagctc 120ccaggaacgg
cccccaaact cctcatctat ggtaataatc agcggccctc aggggtccct
180gaccgattct ctggctccaa gtctggcacc tcagcctccc tggccatcag
tgggctccag 240tctgagaatg aggctgatta ttactgtgca gcatgggatg
acagcctgaa tggtccggta 300ttcggccgag ggaccaaggt caccgtccta ggtgag
33616112PRTHomo sapiens 16Gln Ser Val Leu Thr Gln Pro Pro Ser Ala
Ser Gly Thr Pro Gly Gln1 5 10 15Arg Val Thr Ile Ser Cys Ser Gly Ser
Asn Ser Asn Ile Gly Ser Asn 20 25 30Ser Val Asn Trp Tyr Gln Gln Leu
Pro Gly Thr Ala Pro Lys Leu Leu 35 40 45Ile Tyr Gly Asn Asn Gln Arg
Pro Ser Gly Val Pro Asp Arg Phe Ser 50 55 60Gly Ser Lys Ser Gly Thr
Ser Ala Ser Leu Ala Ile Ser Gly Leu Gln65 70 75 80Ser Glu Asn Glu
Ala Asp Tyr Tyr Cys Ala Ala Trp Asp Asp Ser Leu 85 90 95Asn Gly Pro
Val Phe Gly Arg Gly Thr Lys Val Thr Val Leu Gly Glu 100 105
1101712PRTHomo sapiens 17Ser Gly Gly Ser Ile Arg Ser Thr Arg Trp
Trp Ser1 5 101816PRTHomo sapiens 18Glu Ile Tyr His Ser Gly Ser Thr
Asn Tyr Asn Pro Ser Leu Lys Ser1 5 10 151913PRTHomo sapiens 19Gln
Asp Tyr Gly Asp Ser Gly Asp Trp Tyr Phe Asp Leu1 5 102013PRTHomo
sapiens 20Thr Arg Ser Ser Gly Ser Ile Ala Ser Asn Ser Val Gln1 5
10217PRTHomo sapiens 21Glu Asp Asn Gln Arg Pro Ser1 5229PRTHomo
sapiens 22Gln Ser Ser Asp Ser Ser Ala Val Val1 5235PRTHomo sapiens
23Ser Tyr Gly Ile Ser1 52417PRTHomo sapiens 24Trp Ile Ser Ala Tyr
Asn Gly Asn Thr Asn Tyr Ala Gln Lys Leu Gln1 5 10 15Gly2510PRTHomo
sapiens 25Asp Ala Asp Tyr Ser Ser Gly Ser Gly Tyr1 5 102611PRTHomo
sapiens 26Ser Gly Asp Ala Leu Pro Lys Gln Tyr Ala Tyr1 5
10277PRTHomo sapiens 27Lys Asp Thr Glu Arg Pro Ser1 52811PRTHomo
sapiens 28Gln Ser Ala Asp Asn Ser Ile Thr Tyr Arg Val1 5
10295PRTHomo sapiens 29Ser Tyr Tyr Ile His1 53017PRTHomo sapiens
30Ile Ile Asn Pro Arg Gly Ala Thr Ile Ser Tyr Ala Gln Lys Phe Gln1
5 10 15Gly3110PRTHomo sapiens 31Ala Gly Ile Tyr Gly Phe Asp Phe Asp
Tyr1 5 103214PRTHomo sapiens 32Thr Gly Thr Ser Asn Asp Val Gly Gly
Tyr Asn Tyr Val Ser1 5 10337PRTHomo sapiens 33Asp Val Thr Asn Arg
Pro Ser1 53412PRTHomo sapiens 34Ser Ser Tyr Thr Ile Val Thr Asn Phe
Glu Val Leu1 5 10357PRTHomo sapiens 35Ser Gly Ala Tyr Tyr Trp Ser1
53616PRTHomo sapiens 36Tyr Ile Tyr Tyr Asn Gly Asn Thr Tyr Tyr Asn
Pro Ser Leu Arg Ser1 5 10 153717PRTHomo sapiens 37Ala Ser Asp Tyr
Val Trp Gly Gly Tyr Arg Tyr Met Asp Ala Phe Asp1 5 10
15Ile3813PRTHomo sapiens 38Ser Gly Ser Asn Ser Asn Ile Gly Ser Asn
Ser Val Asn1 5 10397PRTHomo sapiens 39Gly Asn Asn Gln Arg Pro Ser1
54011PRTHomo sapiens 40Ala Ala Trp Asp Asp Ser Leu Asn Gly Pro Val1
5 1041288PRTHomo sapiens 41Met Gln Ile Pro Gln Ala Pro Trp Pro Val
Val Trp Ala Val Leu Gln1 5 10 15Leu Gly Trp Arg Pro Gly Trp Phe Leu
Asp Ser Pro Asp Arg Pro Trp 20 25 30Asn Pro Pro Thr Phe Phe Pro Ala
Leu Leu Val Val Thr Glu Gly Asp 35 40 45Asn Ala Thr Phe Thr Cys Ser
Phe Ser Asn Thr Ser Glu Ser Phe Val 50 55 60Leu Asn Trp Tyr Arg Met
Ser Pro Ser Asn Gln Thr Asp Lys Leu Ala65 70 75 80Ala Phe Pro Glu
Asp Arg Ser Gln Pro Gly Gln Asp Cys Arg Phe Arg 85 90 95Val Thr Gln
Leu Pro Asn Gly Arg Asp Phe His Met Ser Val Val Arg 100 105 110Ala
Arg Arg Asn Asp Ser Gly Thr Tyr Leu Cys Gly Ala Ile Ser Leu 115 120
125Ala Pro Lys Ala Gln Ile Lys Glu Ser Leu Arg Ala Glu Leu Arg Val
130 135 140Thr Glu Arg Arg Ala Glu Val Pro Thr Ala His Pro Ser Pro
Ser Pro145 150 155 160Arg Pro Ala Gly Gln Phe Gln Thr Leu Val Val
Gly Val Val Gly Gly 165 170 175Leu Leu Gly Ser Leu Val Leu Leu Val
Trp Val Leu Ala Val Ile Cys 180 185 190Ser Arg Ala Ala Arg Gly Thr
Ile Gly Ala Arg Arg Thr Gly Gln Pro 195 200 205Leu Lys Glu Asp Pro
Ser Ala Val Pro Val Phe Ser Val Asp Tyr Gly 210 215 220Glu Leu Asp
Phe Gln Trp Arg Glu Lys Thr Pro Glu Pro Pro Val Pro225 230 235
240Cys Val Pro Glu Gln Thr Glu Tyr Ala Thr Ile Val Phe Pro Ser Gly
245 250 255Met Gly Thr Ser Ser Pro Ala Arg Arg Gly Ser Ala Asp Gly
Pro Arg 260 265 270Ser Ala Gln Pro Leu Arg Pro Glu Asp Gly His Cys
Ser Trp Pro Leu 275 280 28542320DNAHomo sapiens 42gtcagcccaa
ggctgccccc tcggtcactc tgttcccgcc ctcctctgag gagcttcaag 60ccaacaaggc
cacactggtg tgtctcataa gtgacttcta cccgggagcc gtgacagtgg
120cctggaaggc agatagcagc cccgtcaagg cgggagtgga gaccaccaca
ccctccaaac 180aaagcaacaa caagtacgcg gccagcagct atctgagcct
gacgcctgag cagtggaagt 240cccacagaag ctacagctgc caggtcacgc
atgaagggag caccgtggag aagacagtgg 300cccctacaga atgttcatag
32043106PRTHomo sapiens 43Gly Gln Pro Lys Ala Ala Pro Ser Val Thr
Leu Phe Pro Pro Ser Ser1 5 10 15Glu Glu Leu Gln Ala Asn Lys Ala Thr
Leu Val Cys Leu Ile Ser Asp 20 25 30Phe Tyr Pro Gly Ala Val Thr Val
Ala Trp Lys Ala Asp Ser Ser Pro 35 40 45Val Lys Ala Gly Val Glu Thr
Thr Thr Pro Ser Lys Gln Ser Asn Asn 50 55 60Lys Tyr Ala Ala Ser Ser
Tyr Leu Ser Leu Thr Pro Glu Gln Trp Lys65 70 75 80Ser His Arg Ser
Tyr Ser Cys Gln Val Thr His Glu Gly Ser Thr Val 85 90 95Glu Lys Thr
Val Ala Pro Thr Glu Cys Ser 100 10544960DNAHomo sapiens
44cctccaccaa gggcccatcg gtcttccccc tggcaccctc ctccaagagc acctctgggg
60gcacagcggc cctgggctgc ctggtcaagg actacttccc cgaaccggtg acggtgtcgt
120ggaactcagg cgccctgacc agcggcgtgc acaccttccc ggctgtccta
cagtcctcag 180gactctactc cctcagcagc gtggtgaccg tgccctccag
cagcttgggc acccagacct 240acatctgcaa cgtgaatcac aagcccagca
acaccaaggt ggacaagaaa gttgagccca 300aatcttgtga caaaactcac
acatgcccac cgtgcccagc acctgaactc ctggggggac 360cgtcagtctt
cctcttcccc ccaaaaccca aggacaccct catgatctcc cggacccctg
420aggtcacatg cgtggtggtg gacgtgagcc acgaagaccc tgaggtcaag
ttcaactggt 480acgtggacgg cgtggaggtg cataatgcca agacaaagcc
gcgggaggag cagtacaaca 540gcacgtaccg tgtggtcagc gtcctcaccg
tcctgcacca ggactggctg aatggcaagg 600agtacaagtg caaggtctcc
aacaaagccc tcccagcccc catcgagaaa accatctcca 660aagccaaagg
gcagccccga gaaccacagg tgtacaccct gcccccatcc cgggaggaga
720tgaccaagaa ccaggtcagc ctgacctgcc tggtcaaagg cttctatccc
agcgacatcg 780ccgtggagtg ggagagcaat gggcagccgg agaacaacta
caagaccacg cctcccgtgc 840tggactccga cggctccttc ttcctctata
gcaagctcac cgtggacaag agcaggtggc 900agcaggggaa cgtcttctca
tgctccgtga tgcatgaggc tctgcacaac cactacacgc 96045330PRTHomo sapiens
45Ala Ser Thr Lys Gly Pro Ser Val Phe Pro Leu Ala Pro Ser Ser Lys1
5 10 15Ser Thr Ser Gly Gly Thr Ala Ala Leu Gly Cys Leu Val Lys Asp
Tyr 20 25 30Phe Pro Glu Pro Val Thr Val Ser Trp Asn Ser Gly Ala Leu
Thr Ser
35 40 45Gly Val His Thr Phe Pro Ala Val Leu Gln Ser Ser Gly Leu Tyr
Ser 50 55 60Leu Ser Ser Val Val Thr Val Pro Ser Ser Ser Leu Gly Thr
Gln Thr65 70 75 80Tyr Ile Cys Asn Val Asn His Lys Pro Ser Asn Thr
Lys Val Asp Lys 85 90 95Lys Val Glu Pro Lys Ser Cys Asp Lys Thr His
Thr Cys Pro Pro Cys 100 105 110Pro Ala Pro Glu Leu Leu Gly Gly Pro
Ser Val Phe Leu Phe Pro Pro 115 120 125Lys Pro Lys Asp Thr Leu Met
Ile Ser Arg Thr Pro Glu Val Thr Cys 130 135 140Val Val Val Asp Val
Ser His Glu Asp Pro Glu Val Lys Phe Asn Trp145 150 155 160Tyr Val
Asp Gly Val Glu Val His Asn Ala Lys Thr Lys Pro Arg Glu 165 170
175Glu Gln Tyr Asn Ser Thr Tyr Arg Val Val Ser Val Leu Thr Val Leu
180 185 190His Gln Asp Trp Leu Asn Gly Lys Glu Tyr Lys Cys Lys Val
Ser Asn 195 200 205Lys Ala Leu Pro Ala Pro Ile Glu Lys Thr Ile Ser
Lys Ala Lys Gly 210 215 220Gln Pro Arg Glu Pro Gln Val Tyr Thr Leu
Pro Pro Ser Arg Glu Glu225 230 235 240Met Thr Lys Asn Gln Val Ser
Leu Thr Cys Leu Val Lys Gly Phe Tyr 245 250 255Pro Ser Asp Ile Ala
Val Glu Trp Glu Ser Asn Gly Gln Pro Glu Asn 260 265 270Asn Tyr Lys
Thr Thr Pro Pro Val Leu Asp Ser Asp Gly Ser Phe Phe 275 280 285Leu
Tyr Ser Lys Leu Thr Val Asp Lys Ser Arg Trp Gln Gln Gly Asn 290 295
300Val Phe Ser Cys Ser Val Met His Glu Ala Leu His Asn His Tyr
Thr305 310 315 320Gln Lys Ser Leu Ser Leu Ser Pro Gly Lys 325
33046366DNAHomo sapiens 46ggcgcgcact ccgaggtgca gctggtgcag
tctgggggag gcgtggttca gcctgggagg 60tccctgagac tctcctgtgc agcgtctgga
ttcaccttta gtagctattg gatgagctgg 120gtccgccagg ctccagggaa
ggggctggag tgggtctcag ctattagtgg tagtggtggt 180agcacatact
acgcagactc cgtgaagggc cggttcacca tctccagaga caattccaag
240aacacgctgt atctgcaaat gaacagccta agagccgagg acacggccgt
atattactgt 300gcgaaagaga actggggatc gtacttcgat ctctgggggc
aagggaccac ggtcaccgtc 360tcctca 36647125PRTHomo sapiens 47Gly Ala
His Ser Glu Val Gln Leu Val Gln Ser Gly Gly Gly Val Val1 5 10 15Gln
Pro Gly Arg Ser Leu Arg Leu Ser Cys Ala Ala Ser Gly Phe Thr 20 25
30Phe Ser Ser Tyr Trp Cys Asp Arg Met Ser Trp Val Arg Gln Ala Pro
35 40 45Gly Lys Gly Leu Glu Trp Val Ser Ala Ile Ser Gly Ser Gly Gly
Ser 50 55 60Thr Tyr Tyr Ala Asp Ser Val Lys Gly Arg Phe Thr Ile Ser
Arg Asp65 70 75 80Asn Ser Lys Asn Thr Leu Tyr Leu Gln Met Asn Ser
Leu Arg Ala Glu 85 90 95Asp Thr Ala Val Tyr Tyr Cys Ala Lys Glu Asn
Trp Gly Ser Tyr Phe 100 105 110Asp Leu Trp Gly Gln Gly Thr Thr Val
Thr Val Ser Ser 115 120 12548332DNAHomo sapiens 48ggcgtgcact
ccgacatcgt gatgacccag tctccttcca ccctgtctgc atctgtagga 60gacagagtca
ccatcacttg ccgggccagt cagggtatta gtagctggtt ggcctggtat
120cagcagaaac cagggagagc ccctaaggtc ttgatctata aggcatctac
tttagaaagt 180ggggtcccat caaggttcag cggcagtgga tctgggacag
atttcactct caccatcagc 240agtctgcaac ctgaagattt tgcaacttac
tactgtcaac agagttacag taccccgtgg 300acgttcggcc aggggaccaa
gctggaaatc aa 33249112PRTHomo sapiens 49Gly Val His Ser Asp Ile Val
Met Thr Gln Ser Pro Ser Thr Leu Ser1 5 10 15Ala Ser Val Gly Asp Arg
Val Thr Ile Thr Cys Arg Ala Ser Gln Gly 20 25 30Ile Ser Ser Trp Leu
Ala Trp Tyr Gln Gln Lys Pro Gly Arg Ala Pro 35 40 45Lys Val Leu Ile
Tyr Lys Ala Ser Thr Leu Glu Ser Gly Val Pro Ser 50 55 60Arg Phe Ser
Gly Ser Gly Ser Gly Thr Asp Phe Thr Leu Thr Ile Ser65 70 75 80Ser
Leu Gln Pro Glu Asp Phe Ala Thr Tyr Tyr Cys Gln Gln Ser Tyr 85 90
95Ser Thr Pro Trp Thr Phe Gly Gln Gly Thr Lys Leu Glu Ile Lys Arg
100 105 110506PRTHomo sapiens 50Ser Ser Tyr Trp Met Ser1
55117PRTHomo sapiens 51Ala Ile Ser Gly Ser Gly Gly Ser Thr Tyr Tyr
Ala Asp Ser Val Lys1 5 10 15Gly529PRTHomo sapiens 52Glu Asn Trp Gly
Ser Tyr Phe Asp Leu1 55311PRTHomo sapiens 53Arg Ala Ser Gln Gly Ile
Ser Ser Trp Leu Ala1 5 10547PRTHomo sapiens 54Lys Ala Ser Thr Leu
Glu Ser1 5559PRTHomo sapiens 55Gln Gln Ser Tyr Ser Thr Pro Trp Thr1
556288PRTMurine 56Met Trp Val Arg Gln Val Pro Trp Ser Phe Thr Trp
Ala Val Leu Gln1 5 10 15Leu Ser Trp Gln Ser Gly Trp Leu Leu Glu Val
Pro Asn Gly Pro Trp 20 25 30Arg Ser Leu Thr Phe Tyr Pro Ala Trp Leu
Thr Val Ser Glu Gly Ala 35 40 45Asn Ala Thr Phe Thr Cys Ser Leu Ser
Asn Trp Ser Glu Asp Leu Met 50 55 60Leu Asn Trp Asn Arg Leu Ser Pro
Ser Asn Gln Thr Glu Lys Gln Ala65 70 75 80Ala Phe Cys Asn Gly Leu
Ser Gln Pro Val Gln Asp Ala Arg Phe Gln 85 90 95Ile Ile Gln Leu Pro
Asn Arg His Asp Phe His Met Asn Ile Leu Asp 100 105 110Thr Arg Arg
Asn Asp Ser Gly Ile Tyr Leu Cys Gly Ala Ile Ser Leu 115 120 125His
Pro Lys Ala Lys Ile Glu Glu Ser Pro Gly Ala Glu Leu Val Val 130 135
140Thr Glu Arg Ile Leu Glu Thr Ser Thr Arg Tyr Pro Ser Pro Ser
Pro145 150 155 160Lys Pro Glu Gly Arg Phe Gln Gly Met Val Ile Gly
Ile Met Ser Ala 165 170 175Leu Val Gly Ile Pro Val Leu Leu Leu Leu
Ala Trp Ala Leu Ala Val 180 185 190Phe Cys Ser Thr Ser Met Ser Glu
Ala Arg Gly Ala Gly Ser Lys Asp 195 200 205Asp Thr Leu Lys Glu Glu
Pro Ser Ala Ala Pro Val Pro Ser Val Ala 210 215 220Tyr Glu Glu Leu
Asp Phe Gln Gly Arg Glu Lys Thr Pro Glu Leu Pro225 230 235 240Thr
Ala Cys Val His Thr Glu Tyr Ala Thr Ile Val Phe Thr Glu Gly 245 250
255Leu Gly Ala Ser Ala Met Gly Arg Arg Gly Ser Ala Asp Gly Leu Gln
260 265 270Gly Pro Arg Pro Pro Arg His Glu Asp Gly His Cys Ser Trp
Pro Leu 275 280 28557321DNAHomo sapiens 57actgtggctg caccatctgt
cttcatcttc ccgccatctg atgagcagtt gaaatctgga 60actgcctctg ttgtgtgcct
gctgaataac ttctatccca gagaggccaa agtacagtgg 120aaggtggata
acgccctcca atcgggtaac tcccaggaga gtgtcacaga gcaggacagc
180aaggacagca cctacagcct cagcagcacc ctgacgctga gcaaagcaga
ctacgagaaa 240cacaaagtct acgcctgcga agtcacccat cagggcctga
gctcgcccgt cacaaagagc 300ttcaacaggg gagagtgtta g 32158108PRTHomo
sapiens 58His Met Thr Val Ala Ala Pro Ser Val Phe Ile Phe Pro Pro
Ser Asp1 5 10 15Glu Gln Leu Lys Ser Gly Thr Ala Ser Val Val Cys Leu
Leu Asn Asn 20 25 30Phe Tyr Pro Arg Glu Ala Lys Val Gln Trp Lys Val
Asp Asn Ala Leu 35 40 45Gln Ser Gly Asn Ser Gln Glu Ser Val Thr Glu
Gln Asp Ser Lys Asp 50 55 60Ser Thr Tyr Ser Leu Ser Ser Thr Leu Thr
Leu Ser Lys Ala Asp Tyr65 70 75 80Glu Lys His Lys Val Tyr Ala Cys
Glu Val Thr His Gln Gly Leu Ser 85 90 95Ser Pro Val Thr Lys Ser Phe
Asn Arg Gly Glu Cys 100 105
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