ANTI-TRKA ANTIBODIES AND USES THEREOF

Abstract

An antibody or an antigen-binding fragment thereof is capable of specifically recognizing TrkA and uses thereof. The antibody contains a CDR sequence selected from at least one of the following or an amino acid sequence having at least 95% identity with it: heavy chain variable region CDR sequences: SEQ ID NO: 1˜27, light chain variable region CDR sequences: SEQ IN NO: 28˜54. The above antibody can specifically targeted-bind to the TrkA receptor and block the binding of NGF to TrkA.

Claims

1.-59. (canceled)

60. An antibody or antigen-binding fragment thereof capable of specifically recognizing TrkA, wherein the antibody comprises a CDR sequence selected from at least one of the following: heavy chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 1, 2 and 3, or an amino acid sequence having at least 95% identity with SEQ ID NO: 1, 2 and 3, respectively; or heavy chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 4, 5 and 6, or an amino acid sequence having at least 95% identity with SEQ ID NO: 4, 5 and 6, respectively; or heavy chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 7, 8 and 9, or an amino acid sequence having at least 95% identity with SEQ ID NO: 7, 8 and 9, respectively; or heavy chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 10, 11 and 12, or an amino acid sequence having at least 95% identity with SEQ ID NO: 10, 11 and 12, respectively; or heavy chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 13, 14 and 15, or an amino acid sequence having at least 95% identity with SEQ ID NO: 13, 14 and 15, respectively; or heavy chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 16, 17 and 18, or an amino acid sequence having at least 95% identity with SEQ ID NO: 16, 17 and 18, respectively; or heavy chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 19, 20 and 21, or an amino acid sequence having at least 95% identity with SEQ ID NO: 19, 20 and 21, respectively; or heavy chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 22, 23 and 24, or an amino acid sequence having at least 95% identity with SEQ ID NO: 22, 23 and 24, respectively; or heavy chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 25, 26 and 27, or an amino acid sequence having at least 95% identity with SEQ ID NO: 25, 26 and 27, respectively; and light chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 28, 29 and 30, or an amino acid sequence having at least 95% identity with SEQ ID NO: 28, 29 and 30, respectively; or light chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 31, 32 and 33, or an amino acid sequence having at least 95% identity with SEQ ID NO: 31, 32 and 33, respectively; or light chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 34, 35 and 36, or an amino acid sequence having at least 95% identity with SEQ ID NO: 34, 35 and 36, respectively; or light chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 37, 38 and 39, or an amino acid sequence having at least 95% identity with SEQ ID NO: 37, 38 and 39, respectively; or light chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 40, 41 and 42, or an amino acid sequence having at least 95% identity with SEQ ID NO: 40, 41 and 42, respectively; or light chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 43, 44 and 45, or an amino acid sequence having at least 95% identity with SEQ ID NO: 43, 44 and 45, respectively; or light chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 46, 47 and 48, or an amino acid sequence having at least 95% identity with SEQ ID NO: 46, 47 and 48, respectively; or light chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 49, 50 and 51, or an amino acid sequence having at least 95% identity with SEQ ID NO: 49, 50 and 51, respectively; or light chain variable region CDR1, CDR2, CDR3 sequences as shown in SEQ ID NO: 52, 53 and 54, or an amino acid sequence having at least 95% identity with SEQ ID NO: 52, 53 and 54, respectively.

61. The antibody or antigen-binding fragment thereof according to claim 60, wherein the antibody or antigen-binding fragment thereof specifically recognizes the extracellular region of TrkA.

62. The antibody or antigen-binding fragment thereof according to claim 60, wherein the antibody has a heavy chain variable region of the amino acid sequence shown in any one of SEQ ID NO: 55˜63.

63. The antibody or antigen-binding fragment thereof according to claim 60, wherein the antibody has a light chain variable region of the amino acid sequence shown in any one of SEQ ID NO: 64˜72.

64. The antibody or antigen-binding fragment thereof according to claim 60, wherein the full-length sequence of the constant region of the antibody is shown in SEQ ID NO: 74 or 75.

65. The antibody or the antigen-binding fragment thereof according to claim 60, wherein the antibody has a heavy chain of the amino acid sequence shown in any one of SEQ ID NO: 76˜84 and a light chain of the amino acid sequence shown in any one of SEQ ID NO: 85˜93.

66. The antibody or antigen-binding fragment thereof according to claim 60, wherein the antibody is a single chain antibody fragment, a multimeric antibody, a CDR-grafted antibody, or a small molecule antibody; wherein the antibody is a single chain antibody fragment, and the antibody has the amino acid sequence shown in SEQ ID NO: 94˜111.

67. A nucleic acid molecule, wherein the nucleic acid molecule encodes the antibody or the antigen-binding fragment thereof according to claim 60; wherein the nucleic acid molecule is DNA; wherein the nucleic acid molecule has a nucleotide sequence as shown in any one of SEQ ID NO: 112˜120, or a nucleotide sequence as shown in any one of SEQ ID NO: 121˜129, or a nucleotide sequence as shown in any one of SEQ ID NO: 130˜147.

68. A pharmaceutical composition comprising the antibody or antigen-binding fragment thereof according to claim 60.

69. A kit for detecting TrkA, comprising the antibody or antigen-binding fragment thereof according to claim 60.

70. A mouse B cell, wherein the genome of the B cell carries a sequence encoding a constant region, and the constant region sequence has S108P, F114A, L115A, R289K mutations and 327 K deletion mutations compared with the constant region of human IgG4.

71. A method of treating or preventing pain, cancer, inflammation or inflammatory diseases, neurodegenerative diseases, Sjogren's syndrome, endometriosis, diabetic peripheral neuropathy, prostatitis, pelvic pain syndrome, diseases related to imbalance in the regulation of bone remodeling and diseases caused by abnormal signaling of connective tissue growth factor in a subject, comprising administering to a subject in need thereof a therapeutically effective amount of the antibody or antigen-binding fragment thereof according to claim 60.

72. The method of treating or preventing neuropathic pain, inflammatory pain, cancer-related pain, fracture-related pain, surgery-related pain, inflammatory lung disease, interstitial cystitis, painful bladder syndrome, inflammatory bowel disease, inflammatory skin disease, Raynaud's syndrome, idiopathic pulmonary fibrosis, scar (hypertrophy, keloid type and other forms), sclerosis, endocardial myocardial fibrosis, atrial fibrosis, bone marrow fibrosis, progressive massive fibrosis (lung), renal-derived systemic fibrosis, scleroderma, systemic sclerosis, joint fibrosis, ocular fibrosis, non-small cell lung cancer, papillary thyroid cancer, glioblastoma multiforme, colorectal cancer, melanoma, bile duct cancer or sarcoma, acute myeloid leukemia, large cell neuroendocrine cancer, neuroblastoma, prostate cancer, pancreatic cancer, melanoma, head and neck squamous cell carcinoma or gastric cancer in a subject, comprising administering to a subject in need thereof a therapeutically effective amount of the antibody or antigen-binding fragment thereof according to claim 60.

73. A method of detecting TrkA or diagnosing a TrkA-related disease in a subject comprising administering to a subject in need thereof a therapeutically effective amount of the antibody or antigen-binding fragment thereof according to claim 60.

74. A method of detecting TrkA or diagnosing a TrkA-related disease comprising culturing the mouse B cell according to claim 70 so that the monoclonal antibody is produced.

75. A pharmaceutical composition comprising the nucleic acid molecule according to claim 67.

76. A method of treating or preventing pain, cancer, inflammation or inflammatory diseases, neurodegenerative diseases, Sjogren's syndrome, endometriosis, diabetic peripheral neuropathy, prostatitis, pelvic pain syndrome, diseases related to imbalance in the regulation of bone remodeling and diseases caused by abnormal signaling of connective tissue growth factor in a subject, comprising administering to a subject in need thereof a therapeutically effective amount of the nucleic acid molecule according to claim 67.

77. The method of treating or preventing neuropathic pain, inflammatory pain, cancer-related pain, fracture-related pain, surgery-related pain, inflammatory lung disease, interstitial cystitis, painful bladder syndrome, inflammatory bowel disease, inflammatory skin disease, Raynaud's syndrome, idiopathic pulmonary fibrosis, scar (hypertrophy, keloid type and other forms), sclerosis, endocardial myocardial fibrosis, atrial fibrosis, bone marrow fibrosis, progressive massive fibrosis (lung), renal-derived systemic fibrosis, scleroderma, systemic sclerosis, joint fibrosis, ocular fibrosis, non-small cell lung cancer, papillary thyroid cancer, glioblastoma multiforme, colorectal cancer, melanoma, bile duct cancer or sarcoma, acute myeloid leukemia, large cell neuroendocrine cancer, neuroblastoma, prostate cancer, pancreatic cancer, melanoma, head and neck squamous cell carcinoma or gastric cancer in a subject, comprising administering to a subject in need thereof a therapeutically effective amount of the antibody or antigen-binding fragment thereof according to claim 67.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0081] FIG. 1 is an experimental result diagram of nine monoclonal hybridoma cell lines capable of producing anti-TrkA monoclonal antibodies that block the binding of NGF and TrkA at the molecular level, obtained by screening by ELISA method according to the embodiment of the present invention;

[0082] FIG. 2 is an experimental result diagram of nine monoclonal hybridoma cell lines capable of producing anti-TrkA monoclonal antibodies that block the binding of NGF and TrkA at the cell level, obtained by flow screening according to the embodiment of the present invention, % parent (percentage);

[0083] FIG. 3 is an experimental result diagram of the detection of the binding of the monoclonal antibody produced by each positive clone supernatant to the Mouse-TrKA receptor according to the ELISA method according to the embodiment of the present invention;

[0084] FIG. 4 is an experimental result diagram of the evaluation of blocking activity of test antibodies using HEK-293T-TrkA cell model according to the embodiment of the present invention, % parent (percentage);

[0085] FIG. 5 is an experimental result diagram of Tanezumab used to verify whether the NIH-3T3-TrkA cell model can be used to evaluate the activity of a drug (test drug) in vitro that inhibits the NGF-TrkA pathway according to the embodiment of the present invention;

[0086] FIG. 6 is an experimental result diagram of the tyrosine phosphorylation level of TrkA protein under the action of the test antibody and the positive antibody MNAC13 by the AlphaLISA method according to an embodiment of the invention;

[0087] FIG. 7 is a result diagram of detecting an affinity EC.sub.50 of a test antibody by flow cytometry according to the embodiment of the present invention;

[0088] FIG. 8A-8G is a result diagram of evaluating the specificity of the binding of a test antibody to a target TrKA by an ELISA method according to the embodiment of the present invention;

[0089] FIG. 9 is a result diagram of detecting the binding ability of the test antibody to the Mouse-TrKA protein by applying an ELISA method according to the embodiment of the present invention;

[0090] FIG. 10 is a result diagram of detecting the binding ability of the test antibody to the Mouse-TrKA protein by flow cytometry according to the embodiment of the present invention;

[0091] FIG. 11 is a result diagram of detecting the inhibitory effect of the test antibody on the binding of Mouse-NGF and Mouse-TrKA by applying an ELISA method according to the embodiment of the present invention;

[0092] FIG. 12 is a result diagram of detecting the inhibitory effect of the test antibody on the binding of Mouse-NGF and Mouse-TrKA by flow cytometry according to the embodiment of the present invention;

[0093] FIG. 13 is a result diagram of detecting the inhibitory effect of the test antibody on the binding of Mouse-NGF and Mouse-TrKA by applying an ELISA method according to the embodiment of the present invention;

[0094] FIG. 14 is a result diagram of evaluating the analgesic activity of a test antibody in vivo using a formalin pain model according to the embodiment of the present invention; and

[0095] FIG. 15 is a result diagram of evaluating the analgesic activity of a test antibody in vivo using a Freund's adjuvant-induced inflammation and pain model according to the embodiment of the present invention.

SPECIFIC IMPLEMENTATION

[0096] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present invention, but should not be construed as limiting the present invention.

[0097] In the course of describing the present invention, the terms used herein are explained. These explanations are only for the convenience of understanding the scheme, and should not be regarded as limiting the protection scheme of the present invention.

[0098] Antibody

[0099] As used herein, the term “antibody” is an immunoglobulin molecule capable of binding to a specific antigen. It consists of two lighter molecular weight light chains and two heavier molecular weight heavy chains. The heavy (H) and light (L) chains are linked by disulfide bonds to form a tetrapeptide chain molecule. Among them, the amino acid sequence of the amino terminal (N-terminal) of the peptide chain changes greatly, which is called the variable region (V region). The carboxyl terminal (C-terminal) is relatively stable with little change, which is called the constant region (C region). The V regions of the L and H chains are referred to as VL and VH, respectively.

[0100] Some regions in the variable region have a higher degree of change in amino acid composition and arrangement order. They are called hypervariable regions (HVR). Hypervariable regions are where antigens and antibodies bind, so they are also called complementarity-determining region (CDR). There are three CDRs on both the heavy and light chain variable regions.

[0101] The present invention utilizes the extracellular segment of TrkA to obtain highly specific and high affinity anti-TrkA Fab (antigen-binding fragment) antibody fragments through immunization. The antibody fragment can specifically bind to the TrkA antigen, and thus can be used for targeted treatment of diseases such as pain or tumor.

[0102] In some embodiments, the invention provides an antibody or antigen-binding fragment capable of specifically recognizing TrkA, wherein the antibody comprises a CDR sequence selected from at least one of the following or an amino acid sequence having at least 95% identity with it: heavy chain variable region CDR sequences: SEQ ID NO: 1˜27, light chain variable region CDR sequences: SEQ IN NO: 28˜54. In other embodiments, the antibodies or antigen-binding fragments provided by the present invention have conservative amino acid substitutions compared to the above heavy and light chains. “Antigen-binding fragment” refers to an antibody fragment that retains the ability to specifically bind to an antigen (ROR2). “Conservative amino acid substitution” refers to the replacement of an amino acid with a residue that is biologically, chemically, or structurally similar to another amino acid. Biological similarity means that the substitution does not destroy the TrkA antibody or biological activity with the TrkA antigen. Structural similarity refers to side chains with similar lengths of amino acids, such as alanine, glycine, or serine, or side chains of similar size. Chemical similarity means that amino acids have the same charge or are both hydrophilic or hydrophobic. For example, the hydrophobic residues isoleucine, valine, leucine or methionine are substituted with each other. Alternatively, polar amino acid is substituted with another polar amino acid, such as lysine is substituted with arginine, aspartic acid is substituted with glutamic acid, asparagine is substituted with glutamine, threonine is substituted with serine, etc.

[0103] In some embodiments, the present invention provides an antibody or antigen-binding fragment, wherein the antibody or antigen-binding fragment has a heavy chain variable region of the amino acid sequence shown in any one of SEQ ID NO: 55˜63 and has a light chain variable region of the amino acid sequence shown in any one of SEQ ID NO: 64˜72. The inventors can obtain the CDR regions of the above-mentioned anti-heavy chain variable region sequences (as shown in SEQ ID NO: 1˜27) and the CDR regions of the light chain variable region sequence (such as SEQ ID NO: 28˜54) through an antibody sequence alignment database (NCBI, IMGT). In other embodiments, the heavy chain variable region sequence of the antibody or antigen-binding fragment has conservative amino acid substitutions compared to the amino acid sequence shown in SEQ ID NO: 55˜63. In some embodiments, the light chain variable region sequence of the antibody or antigen-binding fragment has conservative amino acid substitutions compared to the amino acid sequence shown in any one of SEQ ID NO: 64˜72. Of course, these conservative amino acid substitutions will not alter the biological function of the antibody or antigen-binding fragment. In some specific ways, these conservative amino acid substitutions can occur on amino acids other than the CDR regions in the heavy and light chain variable regions.

[0104] In some preferred embodiments, the invention provides an anti-TrkA antibody having a heavy chain of the amino acid sequence shown in any one of SEQ ID NO: 76˜84 and having a light chain of the amino acid sequence shown in any one of SEQ ID NO: 85˜93.

[0105] In some preferred embodiments, the present invention provides an anti-TrkA single chain fragment antibody, wherein the antibody has the amino acid sequence shown in SEQ ID NO: 94˜111.

[0106] Nucleic Acid Molecule, Expression Vector, Recombinant Cell

[0107] In the process of preparing or obtaining these antibodies, nucleic acid molecules expressing these antibodies can be connected to different vectors and then express in different cells to obtain corresponding antibodies.

[0108] To this end, the present invention also provides an isolated nucleic acid molecule, which encodes the antibody or antigen-binding fragment described above.

[0109] In some embodiments, the isolated nucleic acid molecule has a nucleotide sequence shown in any one of SEQ ID NO: 112˜120 or has a nucleotide sequence shown in any one of SEQ ID NO: 121˜129 or has a nucleotide sequence as shown in any one of SEQ ID NO: 130˜147.

[0110] In some embodiments, the isolated nucleic acid molecule has at least 90% homology with the nucleotide sequence shown in the above SEQ ID NO: 112˜120, and preferably has at least 95% homology, and more preferably has at least 98%, 99% homology. In at least some embodiments, the isolated polynucleotide has at least 90% homology with the nucleotide sequence shown in SEQ ID NO: 121˜129, and preferably has at least 95% homology, and more preferably has at least 98%, 99% homology. In at least some embodiments, the isolated polynucleotide has at least 90% homology with the nucleotide sequence shown in SEQ ID NO: 130˜147, and preferably has at least 95% homology, and more preferably has at least 98%, 99% homology. These sequences which are homologous to the nucleotide sequences shown in SEQ ID NO: 112˜120 or SEQ ID NO: 121˜129 or SEQ ID NO: 130˜147 can express amino acids similar to SEQ ID NO: 76˜84 or SEQ ID NO: 85˜93 or SEQ ID NO: 94.Math.111, so that they can specifically bind to the TrkA antigen and achieve the targeted function of antibodies.

[0111] In some preferred embodiments, the isolated nucleic acid molecule has a heavy chain nucleotide sequence shown in SEQ ID NO: 112˜120 and a light chain nucleotide sequence shown in SEQ ID NO: 121˜129. These nucleotide sequences are optimized for species and are more easily expressing in mammalian cells.

[0112] The present invention also provides an expression vector, wherein the expression vector comprises the aforementioned isolated nucleic acid molecule. When the aforementioned isolated polynucleotide is ligated to a vector, the polynucleotide can be directly or indirectly connected to control elements on the vector, as long as these control elements can control the translation and expression of the polynucleotide. Of course, these control elements can come directly from the vector itself, or they can be exogenous, that is, not from the vector itself. Of course, the polynucleotide may be operably linked to the control element. “Operably linked” herein refers to the connection of an exogenous gene to a vector, so that control elements in the vector, such as transcription control sequences and translation control sequences, can exert its expected function of regulating the transcription and translation of exogenous genes. Of course, the polynucleotides used to encode the heavy and light chains of the antibodies can be inserted into different vectors independently, and they are usually inserted into the same vector. Commonly used vectors can be, for example, plasmids, phages, and the like. For example Plasmid-X plasmid.

[0113] The invention also provides a recombinant cell, which contains the expression vector. The expression vector can be introduced into mammalian cells, and the recombinant cells are constructed and obtained, and then these recombinant cells can be used to express the antibodies or antigen-binding fragments provided by the present invention. By culturing the recombinant cells, corresponding antibodies can be obtained. These usable mammalian cells may be, for example, CHO cells and the like.

[0114] Pharmaceutical Composition, Kit and Pharmaceutical Uses and Uses in the Preparation of Kits

[0115] The invention also provides a pharmaceutical composition, which comprises the antibody or antigen-binding fragment described above and a pharmaceutically acceptable carrier.

[0116] The anti-TrkA antibodies provided herein can be incorporated into a pharmaceutical composition suitable for administration to a subject. Generally, these pharmaceutical compositions include the anti-TrkA antibodies provided herein as well as a pharmaceutically acceptable carrier. A “pharmaceutically acceptable carrier” may include any and all solvents, dispersion media, coatings, antibacterial and antifungal agents, isotonic and delayed absorption agents, and the like that are physiologically compatible. Specific examples may be one or more of water, saline, phosphate buffered saline, glucose, glycerol, ethanol, and the like, and combinations thereof. In many cases, pharmaceutical compositions include isotonic agents, such as sugars, polyalcohols (such as mannitol, sorbitol), or sodium chloride. Of course, pharmaceutically acceptable carriers may also include minor amounts of auxiliary substances, such as wetting or emulsifying agents, preservatives or buffering agents, to extend the shelf life or efficacy of the antibody.

[0117] For example, the antibodies of the invention can be incorporated into pharmaceutical compositions suitable for parenteral administration (e.g., intravenous, subcutaneous, intraperitoneal, intramuscular). These pharmaceutical compositions can be prepared in various forms. Examples are liquid, semi-solid, and solid dosage forms, including, but not limited to, liquid solutions (e.g., injection solutions and infusion solutions), dispersing or suspending agents, tablets, pills, powders, liposomes, and suppositories. Typical pharmaceutical compositions are in the form of injection solutions or infusion solutions. The antibodies can be administered by intravenous infusion or injection or intramuscular or subcutaneous injection.

[0118] Of course, the anti-TrkA antibodies herein can also be made into kits or part of other diagnostic reagents as needed. According to the embodiment of the present invention, the present invention also provides a kit comprising the above-mentioned TrkA antibody. The kit provided by the present invention can be used, for example, for detection by immunoblotting, immunoprecipitation, etc., which involve using the specific binding properties of TrkA antigen and antibodies. These kits may include any one or more of the following: antagonists, anti-TrkA antibodies or drug reference materials; protein purification columns; immunoglobulin affinity purification buffers; cell assay diluents; instructions or literature, etc. Anti-TrkA antibodies can be used for different types of diagnostic tests, such as the detection of various diseases or the presence of drugs, toxins or other proteins in vitro or in vivo. For example, it can be used to test related diseases by detecting the serum or blood of the subject. Such related diseases may include TrkA-related diseases such as pain, cancer, inflammation or inflammatory diseases, neurodegenerative diseases, Sjogren's syndrome, endometriosis, diabetic peripheral neuropathy, prostatitis, pelvic pain syndrome, diseases related to the imbalance in regulation of bone remodeling and diseases caused by abnormal signaling of connective tissue growth factor, and the like. Of course, the antibodies provided herein can also be used for radioimmunodetection and radioimmunotherapy of the above diseases.

[0119] Specifically, the aforementioned pain, inflammation or inflammatory disease, neurodegenerative diseases, Sjogren's syndrome, endometriosis, diabetic peripheral neuropathy, prostatitis, pelvic pain syndrome, diseases related to the imbalance in regulation of bone remodeling and diseases caused by abnormal signaling of connective tissue growth factor include neuropathic pain, inflammatory pain, cancer-related pain, fracture-related pain, surgery-related pain, inflammatory lung disease, interstitial cystitis, painful bladder syndrome, inflammatory bowel disease, inflammatory skin disease, Raynaud's syndrome, idiopathic pulmonary fibrosis, scar (hypertrophy, keloid type and other forms), sclerosis, endocardial myocardial fibrosis, atrial fibrosis, bone marrow fibrosis, progressive massive fibrosis (lung), renal-derived systemic fibrosis, scleroderma, systemic sclerosis, joint fibrosis, ocular fibrosis.

[0120] These cancers or tumors can be any unregulated cell growth. Specifically, it may be non-small cell lung cancer, papillary thyroid cancer, glioblastoma multiforme, colorectal cancer, melanoma, bile duct cancer or sarcoma, acute myeloid leukemia, large cell neuroendocrine cancer, neuroblastoma, prostate cancer, pancreatic cancer, melanoma, head and neck squamous cell carcinoma or gastric cancer, etc.

[0121] When using the anti-TrkA antibody provided by the present invention to treat the above-mentioned diseases, the anti-TrkA antibody provided by the present invention may be provided to a subject. To this end, the present invention provides a method for treating the above-mentioned diseases, which comprises administering an antibody or an antigen-binding fragment thereof provided by the present invention to a subject in need.

[0122] The solution of the present invention will be explained below with reference to the examples. Those skilled in the art will understand that the following examples are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. If the specific technology or condition is not indicated in the examples, the technology or condition described in the literature in the art or the product description is performed. If the reagents or instruments used are not specified by the manufacturer, they are all conventional products that are commercially available.

Example 1 Screening of Anti-TrkA Monoclonal Antibodies by Hybridoma Technology

[0123] The hybridoma technology and ELISA method were used to screen hybridoma cell lines that could produce anti-TrkA monoclonal antibodies that block the binding of NGF and TrkA at the molecular level. The NCBI database was used to design genes encoding the extracellular region of TrkA protein which are constructed into mammalian eukaryotic expression system. The extracellular region of TrkA protein was expressed and used for screening of anti-TrkA monoclonal antibodies. The extracellular region of the immunogen TrkA protein was derived from Beijing Yiqiao Shenzhou Biotechnology Co., Ltd. After Balb/C mice were immunized three times by intraperitoneal injection, the serum antibody titer of the immunized mice was determined by ELISA method, reaching 10.sup.5. After spleen injection boosted immunity, it was fused with myeloma cells. HAT selection medium and HT selection medium were used for selective culture and screen fused hybridoma cell lines, ELISA method was used to screen positive hybridoma cell lines capable of producing anti-TrkA antibodies, and clonal culture of positive hybridoma cells was performed by limiting dilution method, then stable hybridoma cell lines capable of producing anti-TrkA monoclonal antibodies were selected. After three cloning cultures and four ELISA tests, a total of 147 positive monoclonal hybridoma cell lines were screened. NGF was biotinylated. NGF could bind to the extracellular region of TrkA protein, and anti-TrkA monoclonal antibodies could also bind to the extracellular region of TrkA protein. A competitive experiment was designed to detect the binding of NGF to the extracellular region of the TrkA protein under the action of anti-TrkA monoclonal antibodies by ELISA, and to screen anti-TrkA monoclonal antibodies that block the binding of NGF and TrkA at the molecular level. FIG. 1 shows the results of blocking experiments of 9 hybridoma cell lines that can produce anti-TrkA monoclonal antibodies that block the binding of NGF and TrkA at the molecular level among 147 positive monoclonal hybridoma cell lines, i.e., a total of 9 monoclonal hybridoma cell lines capable of producing anti-TrkA monoclonal antibodies that block the binding of NGF and TrkA at the molecular level are obtained. The experimental results are shown in FIG. 1. In the FIG. 1, OD.sub.450 reflects the NGF signal that binds to the extracellular region of TrkA protein. The higher the reading, the stronger the NGF signal that binds to the extracellular region of TrkA protein, and the less effective the antibody in blocking the binding of NGF to TrkA; as shown in the FIG. 1, compared with the negative clone group, the ELISA readings of the 9 positive clone groups are significantly reduced, and the NGF signal binding to the extracellular region of the TrkA protein is significantly reduced; it can be seen that these 9 positive clones can reduce the NGF signal binding to the extracellular region of TrkA protein by generating anti-TrkA monoclonal antibodies that block the binding of NGF to the extracellular region of TrkA protein.

Example 2 Screening of Anti-TrkA Monoclonal Antibodies by HEK-293T-TrkA Cell Model

[0124] HEK-293T-TrkA cell model was constructed using lentivirus technology, and hybridoma cell lines capable of producing anti-TrkA monoclonal antibodies that block the binding of NGF and TrkA at the cell level were screened by flow cytometry. NGF was biotinylated, and NGF could bind to the extracellular region of TrkA protein on HEK-293T-TrkA cells, and anti-TrkA monoclonal antibodies could also bind to the extracellular region of TrkA protein on HEK-293T-TrkA cells. Competitive experiments were designed to detect the binding of NGF to the extracellular region of TrkA protein on HEK-293T-TrkA cells under the action of anti-TrkA monoclonal antibodies by flow cytometry, and to screen anti-TrkA monoclonal antibodies that block the binding of NGF and TrkA at the cell level. A total of 9 monoclonal hybridoma cell lines capable of producing anti-TrkA monoclonal antibodies that blocked the binding of NGF and TrkA at the cell level were obtained through screening, which are consistent with the results of molecular-level blocking experiments. The experimental results are shown in FIG. 2. In the FIG. 2, The % parent value reflects the NGF signal that binds to the extracellular region of TrkA protein on HEK-293T-TrKA cells. The higher the reading, the stronger the NGF signal that binds to the extracellular region of TrkA protein on HEK-293T-TrKA cells, and the worse the effect of the antibody in blocking the binding of NGF to TrkA; as shown in the FIG. 2, compared with the negative clone group, the % parent value of the 9 positive clone groups is significantly reduced, and the NGF signal binding to the extracellular region of the TrkA protein is significantly reduced; it can be seen that these 9 positive clones can reduce the NGF signal binding to the extracellular region of the TrkA protein on HEK-293T-TrkA cells by generating anti-TrkA monoclonal antibodies that block the binding of NGF to the extracellular region of TrkA protein on HEK-293T-TrkA cells.

Example 3 Detection of Human-Mouse Cross Reaction of Positive Clones Producing Monoclonal Antibodies by ELISA Method

[0125] The binding of monoclonal antibodies produced by the supernatant of each positive clone to the Mouse-TrKA receptor was detected by ELISA method, and the human-mouse cross reaction of positive clones producing monoclonal antibodies was detected. The results are shown in FIG. 3. In FIG. 3, the OD.sub.450 value reflects the strength of the binding of the antibody to the protein. The larger the reading, the stronger the binding of the antibody to the protein. As shown in FIG. 3, the OD.sub.450 value of the 23E12, 21E5, 15D4, and 27H3 groups is around 3.5, which is significantly different from the negative control group; the OD.sub.450 value of the 2008, 1B9, 4H4, 3A5, and 22D12 groups were almost close to 0, and there was no significant difference compared with the negative clone group. It can be seen that clones 23E12, 21E5, 15D4, and 27H3 can produce monoclonal antibodies that bind to both Human-TrKA and Mouse-TrKA, and there is a human-mouse cross reaction.

Example 4 Construction of Vectors

[0126] A series of (2008, 23E12, 27H3, 21E5, 2A5, 4H4, 1B9, 22D12, 15D4) chimeric antibody expression vectors were constructed using molecular cloning methods. Chimeric antibodies were recombinantly expressed in the CHO expression system. The nucleotide sequence encoding the light and heavy chain of a series of (2008, 23E12, 27H3, 21E5, 2A5, 4H4, 1B9, 22D12, 15D4) chimeric monoclonal antibodies was obtained through chemical synthesis by Jinweizhi Biotechnology Co., Ltd. The obtained sequence was double-digested and inserted into the same digestion site of the eukaryotic expression vector to construct a series of (2008, 23E12, 27H3, 21E5, 2A5, 4H4, 1B9, 22D12, 15D4) chimeric antibody expression vectors. Then a series of verified correct expression vectors were extracted with Invitrogen plasmid extraction kit, linearized with restriction enzymes, purified and recovered, and stored at −20° C.

Example 5 Transfection of Vectors Encoding a Series of Chimeric Antibodies and Expression in Cells

[0127] After the CHO host cells were resuscitated with CD CHO medium, the cells were collected for transfection when the cell density was about 8*10.sup.5 cells/mL. The transfected cells were about 1*10.sup.7 cells, and the vector was about 40 μg. The cells were transfected by electric shock method (Bio-Rad, Gene pulser Xcell). The cells were cultured in 20 mL of CD CHO medium after electric shock. The next day of culture, the cells were collected by centrifugation and resuspended in 20 mL of CD CHO medium with MSX to a final concentration of 50 μM. When the cell density was about 0.6*10.sup.6 cell/mL, the obtained mixed clone was subcultured with CD CHO medium, and the passage cell density was about 0.2*10.sup.6 cell/mL. When the cell survival rate was about 90%, the cell culture solution was collected.

Example 6 Purification of Chimeric Antibodies by Collecting Cell Fermentation Medium

[0128] A series of chimeric antibodies were tested at the translation level. Protein A chromatography column was used to purify the collected cell culture solution, and the absorption peaks were collected for mass spectrometry detection. Mass spectrometry detected a series of chimeric antibodies with molecular weights of about 150KD, which was consistent with the theoretical molecular weight. At the same time, the collected samples were detected by 10% SDS-PAGE electrophoresis after reduction and non-reduction. The reduced SDS-PAGE electrophoresis spectrum showed two bands, at about 25KD and 50KD, respectively. The non-reduced SDS-PAGE electrophoresis spectrum showed a single band at about 150KD. The band size of the electrophoresis spectrum is consistent with the theory. The purified sample was dialyzed against 0.02M PBS buffer at pH 7.4 overnight at 4° C.

[0129] In the following Examples 7-16, the inventors evaluated the constructed and purified chimeric antibodies 2008, 23E12, 27H3, 21E5, 2A5, 4H4, 1B9, 22D12, 15D4 for their affinity with TrkA, and the activity of binding to TrkA, and blocking NGF to the extracellular region of the TrkA protein.

Example 7 Evaluation of Blocking Activity of Test Antibodies Using HEK-293T-TrkA Cell Model

[0130] NGF was biotinylated, and NGF could bind to the extracellular region of TrkA protein on HEK-293T-TrkA cells, and anti-TrkA monoclonal antibodies could also bind to the extracellular region of TrkA protein on HEK-293T-TrkA cells. A competitive experiment was designed to detect the binding of NGF to the extracellular region of TrkA protein on HEK-293T-TrkA cells under different concentrations (20 μg/mL, 10 μg/mL, 5 μg/mL, 2.5 μg/mL, 1.25 μg/mL, 0.625 μg/mL, 0.313 μg/mL, 0.156 μg/mL, 0.078 μg/mL, 0.039 μg/mL, 0.019 μg/mL) of test antibodies by flow cytometry, and to study the inhibitory effect of test antibodies on the binding of NGF and TrKA. The experimental results are shown in FIG. 4. In the FIG. 4, the parent % value reflects the NGF signal binding to the extracellular region of TrKA protein on HEK-293T-TrkA cells. The lower the reading, the weaker the NGF signal that binds to the extracellular region of the TrkA protein on HEK-293T-TrkA cells, and the greater the effect of the antibody on inhibiting the binding of NGF to TrKA; as shown in FIG. 4, as the test antibody concentration increases, the parent % value gradually decreases until it approaches zero, i.e., the NGF signal binding to the extracellular region of TrkA protein gradually decreases until there is no NGF binding to the extracellular region of the TrkA protein, and the binding of NGF to TrkA is all inhibited. It can be seen that within a certain concentration range, each test antibody can dose-dependently inhibit the binding of NGF to TrkA at the cellular level.

Example 8 Evaluation of the Activity of Test Antibodies In Vitro Using the NIH-3T3-TrkA Cell Model

[0131] Under NGF stimulation, tyrosine phosphorylation level of the TrkA protein on the membrane of NIH-3T3-TrkA cells was up-regulated, and the TrkA downstream signaling pathway was activated. The test antibody could bind to the TrkA protein on the surface of NIH-3T3-TrkA cell membrane, inhibit NGF stimulation, and down-regulate tyrosine phosphorylation level of TrkA protein. In the test, IgG4 was used as a negative control (the antibody does not bind to NGF and TrkA), tanezumab (anti-NGF monoclonal antibody, the amino acid sequence of the light chain is shown in SEQ ID NO: 149, and the amino acid sequence of the heavy chain is shown in SEQ ID NO: 150, a drug that inhibits the NGF-TrkA pathway) and MNAC13 (anti-TrKA monoclonal antibody, the amino acid sequence of the light chain is shown in SEQ ID NO: 151, the amino acid sequence of the heavy chain is shown in SEQ ID NO: 152, a drug that inhibits the NGF-TrkA pathway) were used as a positive control. Among them, Tanezumab was used to verify whether the NIH-3T3-TrkA cell model could be used to evaluate the in vitro activity of drugs that inhibited the NGF-TrkA pathway (test drugs). The experimental data are shown in FIG. 5. The method of AlphaLISA was used to detect the down-regulation of tyrosine phosphorylation of TrkA protein under the action of different concentrations of test antibody and positive antibody MNAC13, and to measure the activity of test antibodies in vitro. The test results of p-TrkA are shown in FIG. 6. The experimental results show that both the test antibody and the positive antibody MNAC13 can inhibit the NGF-TrKA pathway and dose-dependently down-regulate the tyrosine phosphorylation level of TrkA protein. Among them, the half inhibitory concentration IC.sub.50 of the test antibodies 23E12, 2008, 27H3, 21E5, 1B9, and 4H4 is smaller than of the positive antibody MNAC13. It can be seen that the test antibodies 23E12, 2008, 27H3, 21E5, 1B9, 4H4 have better activity in vitro than the positive antibody MNAC13.

TABLE-US-00010 (SEQ ID NO: 149) DIQMTQSPSSLSASVGDRVTITCRASQSISNNLNWYQQKPGKAPKLLIYY TSRFHSGVPSRFSGSGSGTDFTFTISSLQPEDIATYYCQQEHTLPYTFGQ GTKLEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKV DNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQG LSSPVTKSFNRGEC. (SEQ ID NO: 150) QVQLQESGPGLVKPSETLSLTCTVSGFSLIGYDLNWIRQPPGKGLEWIGI IWGDGTTDYNSAVKSRVTISKDTSKNQFSLKLSSVTAADTAVYYCARGGY WYATSYYFDYWGQGTLVTVSSASTKGPSVFPLAPCSRSTSESTAALGCLV KDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSNFGTQ TYTCNVDHKPSNTKVDKTVERKCCVECPPCPAPPVAGPSVFLFPPKPKDT LMISRTPEVTCVVVDVSHEDPEVQFNWYVDGVEVHNAKTKPREEQFNSTF RVVSVLTVVHQDWLNGKEYKCKVSNKGLPAPIEKTISKTKGQPREPQVYT LPPSREEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPMLDS DGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK. (SEQ ID NO: 151) DIVLTQSPSSLSASVGDRVTITCSASSSVSYMHWYQQKPGQAPKLLIYTT SNLASGVPSRFSGSGSGTDYTLTISSLQPEDVATYYCHQWSSYPWTFGGG TKVEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVD NALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGL SSPVTKSFNRGEC. (SEQ ID NO: 152) EVQLLESGGGLVQPGGSLRLSCAASGFTFSTYTMSWARQAPGKGLEWVAY ISKGGGSTYYPDTVKGRFTISRDNSKNTLYLQMNSLRAEDSAVYYCARGA MFGNDFFFPMDRWGQGTLVTVSSASTKGPSVFPLAPCSRSTSESTAALGC LVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLG TKTYTCNVDHKPSNTKVDKRVESKYGPPCPPCPAPEAAGGPSVFLFPPKP KDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKPREEQFN STYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQ VYTLPPSQEEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPV LDSDGSFFLYSKLTVDKSRWQEGNVFSCSVMHEALHNHYTQKSLSLSLG.

Example 9 Evaluation of the Affinity of Test Antibodies to TrkA Using the Fortebio Method

[0132] The test antibody (23E12, 2008, 21E5, 27H3, 1B9, 4H4, 2A5) samples were diluted with buffer solution (PBS buffer 100 ml, 0.1 gBSA was added and stirred until fully dissolved, then 20 μL Tween 20 was added, well mixed) to 4 concentration gradients (80 nM, 26.67 nM, 8.89 nM, 2.93 nM), respectively. They were added to each well of the sample plate. Through the affinity detection system (OCTET RED 96 SYSTEM), after the TRKA (50 μg/ml, 75 kDa, provided by HEC Labs) protein with a histidine tag bound to a Ni-NTA sensor (Manufacturer: PALL, article NO: 18-5101), the binding of the TRKA protein with each test antibody was automatically detected. The results are shown in Table 1. The K.sub.D value is the equilibrium dissociation constant between the antibody and its antigen, and the K.sub.D value is inversely proportional to the affinity. The K.sub.D value is related to the antibody concentration (the amount of antibody required for a particular experiment). The lower the K.sub.D value (the lower the concentration), the higher the affinity of the antibody. High-affinity antibodies are generally considered to be in the low nanomolar range (10.sup.−9). The results in Table 1 show that the K.sub.D values of the test antibodies (23E12, 2008, 21E5, 27H3, 1B9, 4H4, 2A5) are in the low nanomolar range (10.sup.−9), indicating that the test antibodies have high affinity.

TABLE-US-00011 TABLE 1 Sample ID K.sub.D (M) kon(1/Ms) kon Error kdis(1/s) kdis Error Full R{circumflex over ( )}2 23E12 5.70E−11 1.90E+06 6.33E+04 1.09E−04 7.47E−06 0.944 4H4 1.68E−09 1.39E+05 6.01E+03 2.34E−04 1.55E−05 0.961 20C8 1.15E−10 5.51E+05 2.34E+04 6.33E−05 1.17E−05 0.949 27H3 1.78E−10 1.57E+06 4.53E+04 2.79E−04 7.91E−06 0.929 21E5 1.73E−10 1.01E+06 2.08E+04 1.75E−04 5.60E−06 0.977 1B9 8.99E−10 1.01E+06 6.65E+04 9.04E−04 6.29E−05 0.910 2A5 1.62E−11 2.22E+05 1.42E+04 3.60E−06 1.96E−05 0.944

Example 10 Evaluation of Affinity of Test Antibodies by Flow Cytometry

[0133] The test antibody (23E12, 2008, 21E5, 27H3, 1B9, 4H4, 2A5) samples were diluted with PBS buffer solution to 11 concentration gradients (20 μg/mL, 10 μg/mL, 5 μg/mL, 2.5 μg/mL, 1.25 μg/mL, 0.625 μg/mL, 0.313 μg/mL, 0.156 μg/mL, 0.078 μg/mL, 0.039 μg/mL, 0.019 μg/mL). Flow cytometry was used to detect the binding of test antibodies at various concentration gradients to the TrKA receptors on the surface of HEK-293T-TrKA cells, and the affinity of the test antibodies was evaluated at the cell level. The results are shown in FIG. 7. In FIG. 7, the EC.sub.50 (half-binding concentration) value reflects the affinity of the antibody. The smaller the EC.sub.50 value, the higher the affinity of the antibody. It is generally considered that the EC.sub.50 value of the high-affinity antibody is less than 1.5 μg/mL. The results in FIG. 7 show that the EC.sub.50 values of the test antibodies 23E12, 2008, 21E5, 27H3, 1B9, 4H4, and 2A5 are all lower than 1.5 μg/mL, indicating that the test antibodies have high affinity.

Example 11 Evaluation of Specificity of Binding of Test Antibodies to Target TrKA by ELISA Method

[0134] The TrkA receptor family belongs to receptor tyrosine kinases (RTKs), including TrkA, TrkB, and TrkC, which have high homology. TrkA is a receptor tyrosine kinase of nerve growth factor (NGF) that selectively binds to NGF and is a functional receptor for NGF. In addition to the high-affinity receptor TrkA, NGF can also bind to its low-affinity receptor p75. In the test, the binding of test antibodies at different concentrations (20 μg/mL, 10 μg/mL, 5 μg/mL, 2.5 μg/mL, 1.25 μg/mL, 0.625 μg/mL, 0.313 μg/mL, 0.156 μg/mL, 0.078 μg/mL, 0.039 μg/mL, 0.019 μg/mL) to TrKA, TrKB, TrKC, and P75 respectively was detected by the ELISA method, and the specificity of the test antibody binding to the target TrKA was evaluated. The results are shown in FIG. 8. In the FIG. 8, at a certain antibody concentration, the OD.sub.450 value reflects the binding strength of the antibody to the protein. The larger the reading, the stronger the binding of the antibody to the protein. The experimental results shows that the tested antibodies 23E12, 2008, 27H3, 21E5, 1B9, 4H4, and 2A5 all have good binding to the TrKA receptor (The concentration of the test antibody increases from 0 μg/mL to 20 μg/mL, and the OD.sub.450 value gradually increases until it becomes stable, which is close to about 3), but did not bind to TrKB, TrKC, P75(The concentration of each test antibody increases from 0 μg/mL to 20 μg/mL, and the OD.sub.450 value remains almost unchanged, which is close to 0.). It can be seen that the specificity of the binding of the test antibodies to the target TrKA is very good.

Example 12 Detection of Binding Ability of Test Antibodies to Mouse-TrKA Protein by ELISA Method

[0135] Test antibody (23E12, 21E5) samples were diluted with PBS buffer solution to 11 concentration gradients (20 μg/mL, 10 μg/mL, 5 μg/mL, 2.5 μg/mL, 1.25 μg/mL, 0.625 g/mL, 0.313 μg/mL, 0.156 μg/mL, 0.078 μg/mL, 0.039 μg/mL, 0.019 μg/mL). The binding of the test antibody to the Mouse-TrKA receptor at each concentration gradient was detected by the ELISA method, thus the binding ability of the test antibody to the Mouse-TrKA protein was detected. The results are shown in FIG. 9. In FIG. 9, at a certain antibody concentration, the OD.sub.450 value reflects the binding strength of the antibody to the protein. The larger the reading, the stronger the binding of the antibody to the protein. The experimental results show that the concentration of the test antibody increases from 0 μg/mL to 20 μg/mL, and the OD.sub.450 value gradually increases until it approaches stability, which is close to about 3.5. It can be seen that the test antibodies 23E12, 21E5, and Mouse-TrKA protein all have good binding ability.

Example 13 Detection of Binding Ability of the Test Antibody to Mouse-TrKA Protein by Flow Cytometry

[0136] The test antibody 23E12 samples were diluted with PBS buffer to 11 concentration gradients (20 μg/mL, 10 μg/mL, 5 μg/mL, 2.5 μg/mL, 1.25 μg/mL, 0.625 μg/mL, 0.313 μg/mL, 0.156 μg/mL, 0.078 μg/mL, 0.039 μg/mL, 0.019 μg/mL), and the binding of the test antibody to the Mouse-TrKA receptor on the surface of HEK293T-Mouse-TrKA cells at each concentration gradient was detected by flow cytometry. The binding ability of the antibody to Mouse-TrKA protein was tested. The results are shown in FIG. 10. In FIG. 10, the EC.sub.50 (half the binding concentration) value reflects the binding capacity of the antibody. The smaller the EC.sub.50 value, the stronger the binding capacity of the antibody. The experimental results show that the concentration of the test antibody increases from 0 μg/mL to 20 μg/mL, the % Parent value gradually increases until it approaches stability, and the EC.sub.50 value=0.08012 μg/mL. It can be seen that the test antibody 23E12 has a good binding ability with the Mouse-TrKA receptor on the surface of HEK293T-Mouse-TrKA cells.

Example 14 Detection of Inhibitory Effect of Test Antibodies on the Binding of Mouse-NGF and Mouse-TrKA by ELISA Method

[0137] In the test, IgG4 was used as a negative control (the antibody does not bind to Mouse-NGF and Mouse-TrkA), and Mouse-NGF was biotinylated. Mouse-NGF could bind to Mouse-TrkA protein, and anti-Mouse-TrkA monoclonal antibody could also bind to Mouse-TrkA protein. A competitive experiment was designed to detect the binding of Mouse-NGF and Mouse-TrkA protein under different concentrations (2.5 μg/mL, 0.25 μg/mL) of test antibodies (23E12, 21E5) by ELISA method, Thus the inhibition effect of test antibodies on the binding of Mouse-NGF and Mouse-TrKA was investigated. The experimental results are shown in FIG. 11. In FIG. 11, the OD.sub.450 value reflects the Mouse-NGF signal binding to Mouse-TrkA. The lower the reading, the weaker the Mouse-NGF signal that binds to Mouse-TrkA, and the greater the effect of the antibody on inhibiting the binding of Mouse-NGF and Mouse-TrKA; as shown in FIG. 11, compared with the negative control group, the mouse-NGF signal binding to Mouse-TrkA was significantly reduced under the effects of test antibodies (23E12, 21E5) at different concentrations (2.5 μg/mL, 0.25 μg/mL). It can be seen that the test antibodies 23E12 and 21E5 can inhibit the binding of Mouse-NGF and Mouse-TrKA.

Example 15 Detection of the Inhibitory Effect of the Test Antibody on the Binding of Mouse-NGF and Mouse-TrKA by Flow Cytometry

[0138] Mouse-NGF was biotinylated. Mouse-NGF could bind to the extracellular region of Mouse-TrkA protein on HEK293 T-Mouse-TrkA cells, and anti-Mouse-TrkA monoclonal antibody could also bind to the extracellular region of Mouse-TrkA protein on HEK293T-Mouse-TrkA cells. A competitive experiment was designed to detect the binding of Mouse-NGF to the extracellular region of Mouse-TrkA protein on HEK293T-Mouse-TrkA cells under different concentrations (20 μg/mL, 10 μg/mL, 5 μg/mL, 2.5 μg/mL, 1.25 μg/mL, 0.625 μg/mL, 0.313 μg/mL, 0.156 μg/mL, 0.078 μg/mL, 0.039 μg/mL, 0.019 μg/mL) of test antibodies by flow cytometry, thus the inhibition effect of test antibodies on the binding of Mouse-NGF and Mouse-TrKA was investigated. The experimental results are shown in FIG. 12. In FIG. 12, the parent % value reflects the Mouse-NGF signal that binds to the extracellular region of the Mouse-TrKA protein on the HEK293T-Mouse-TrkA cell. The lower the reading, the weaker the Mouse-NGF signal that binds to the extracellular region of the Mouse-TrkA protein on the HEK293T-Mouse-TrkA cell, and the greater the effect of the antibody on inhibiting the binding of Mouse-NGF and Mouse-TrKA; as shown in FIG. 12, as the concentration of the test antibody increases, the % parent value gradually decreases until it approaches zero, that is, the signal of Mouse-NGF binding to the extracellular region of Mouse-TrkA protein gradually decreases until no Mouse-NGF binds to the extracellular region of Mouse-TrkA protein, and the binding of Mouse-NGF and Mouse-TrkA is all inhibited, IC50=0.05147 μg/mL. It can be seen that within a certain concentration range, the test antibody 23E12 can dose-dependently inhibit the binding of Mouse-NGF and Mouse-TrkA at the cellular level.

Example 16 Detection of the Inhibitory Effect of the Test Antibody on the Binding of Human-NGF and Human-TrKA by ELISA Method

[0139] Mouse-NGF was biotinylated. Mouse-NGF could bind to Mouse-TrkA protein, and anti-Mouse-TrkA monoclonal antibody could also bind to Mouse-TrkA protein. A competitive experiment was designed to detect the binding of Mouse-NGF and Mouse-TrkA protein under different concentrations (20 μg/mL, 10 μg/mL, 5 μg/mL, 2.5 μg/mL, 1.25 μg/mL, 0.625 μg/mL, 0.313 μg/mL, 0.156 μg/mL, 0.078 μg/mL, 0.039 μg/mL, 0.019 μg/mL) of test antibodies by ELISA method, thus the inhibition effect of test antibodies on the binding of Mouse-NGF and Mouse-TrkA was investigated. The experimental results are shown in FIG. 13. In FIG. 13, the OD.sub.450 value reflects the Mouse-NGF signal binding to Mouse-TrkA. The lower the reading, the weaker the Mouse-NGF signal binding to Mouse-TrkA, and the greater the effect of the antibody on inhibiting the binding of Mouse-NGF and Mouse-TrKA; as shown in FIG. 13, as the concentration of the test antibody increases, the OD.sub.450 value gradually decreases until it approaches zero, that is, the signal of Mouse-NGF binding to the extracellular region of Mouse-TrkA protein gradually decreases until almost no Mouse-NGF binds to the extracellular region of Mouse-TrkA protein, and the binding of Mouse-NGF and Mouse-TrkA is almost completely inhibited. It can be seen that within a certain concentration range, the test antibodies 23E12, 2008, 21E5, 27H3, 4H4, 2A5 can dose-dependently inhibit the binding of NGF and TrkA at the molecular level.

Example 17 Evaluation of In Vivo Analgesic Activity of Test Antibodies Using Formalin-Induced Pain Model

[0140] The formalin inflammatory pain model is a validated pain model that produces continuous rather than transient pain stimuli and responses by injecting formalin. This model produces two-phase pain, which are phase I chemically stimulated pain and phase II inflammatory pain. The pain response caused by this model is reproducible and measurable. This model is one of the best models for preclinical pain research, and is widely used to evaluate the analgesic effect of different drugs. In the test, male ICR mice of 6-8 weeks were selected and randomly divided into 6 groups according to body weight before modeling: model group (subcutaneous injection of normal saline), Tanezumab 60 μg/mouse dose group, 20C8 60 μg/mouse dose group, 21E5 60 μg/mouse dose group, 23E12 15 μg/mouse dose group, 23E12 60 μg/mouse dose group, 10 mice in each group. The drug was administered subcutaneously. After 18 hours, 15 μL of 2.5% formalin solution was injected subcutaneously into the back of the right hind paw of the mouse. The number of times that the mouse lifted the foot within 45 minutes was observed. 1-15 min is Phase I pain and 16-45 min is Phase II pain. Generally speaking, Phase I pain reflects acute pain, and Phase II pain reflects chronic pain. The results are shown in FIG. 14 (the data in FIG. 14 are Mean±SEM, n=10/group, * p<0.05 compared with the solvent model group, using single factor analysis of variance plus LSD multiple comparison test). The number of foot lifts in FIG. 14 reflects the pain intensity of the mouse after modeling. The lower the number of foot lifts, the weaker the pain. The results show that compared with the model group, the 23E12 60 μg/mouse dose group can significantly reduce the number of foot lifts in phase II pain of the mouse, and the other dose groups fail to reduce the number of foot lifts of the mouse after modeling. Conclusion: in the formalin-induced pain model, subcutaneous injection of the test antibody 23E12 at 60 μg/mouse is effective for chronic pain, while the positive drug Tanezumab does not exhibit analgesic effects and may not be sensitive to the formalin-induced pain model.

Example 18 Evaluation of In Vivo Analgesic Activity of Test Antibodies Using a Complete Freund's Adjuvant-Induced Inflammation Pain Model

[0141] Complete Freund's adjuvant-induced inflammatory pain model is a pain model that produces chronic inflammatory pain stimuli similar to osteoarthritis and responses by injecting complete Freund's adjuvant in the palms of mice. The pain is measured by the mechanical pain test. The greater the intensity of the mechanical stimulus, the more resistant the animal is to pain. In the test, 8-week-old male ICR mice were selected and randomly divided into 6 groups (15 numbers/group) according to pain sensitivity before modeling: control group (injection of saline 25 μl+subcutaneous injection of saline in the left hind limb plantar of mice), model group (injection of 25 μl CFA induced inflammatory pain+subcutaneous injection of saline in the left hind limb of mice), Tanezumab 60 μg/mouse dose group, 23E12 60 μg/mouse dose group, the drug was injected subcutaneously on the 4th day after modeling, and a mechanical pain test was performed after 36 hr of administration. The results are shown in FIG. 15 (the data in FIG. 15 are Mean±SEM, n=15/group, #p □ 0.05, ## p □ 0.01 compared with the blank control group, * p □ 0.05, ** p □ 0.01 compared with the model group, using nonparametric statistical analysis plus independent sample T test). The ordinate represents the intensity of mechanical stimulus. The greater the pressure threshold of mouse paw withdrawal, the better the analgesic effect. The results show that compared with the model group, subcutaneous injection of 60 μg/mouse 23E12 and 60 μg/mouse tanezumab can significantly increase the pressure threshold of mouse paw withdrawal (P<0.01; P<0.05) and exhibit analgesic effects. Both analgesic effects are equivalent. Conclusion: subcutaneous injection of the test antibody 23E12 at 60 μg/mouse exhibits analgesic effects in a complete Freund's adjuvant-induced inflammatory pain model.

Example 19: Toxicology Test of Test Antibodies

[0142] In this example, the toxicity test to be performed by the inventors is shown in Table 2 below.

TABLE-US-00012 TABLE 2 Mode Species or Research of admin- inquiry project istration system Main research Results Toxicity i.v. SD rat Observing whether No animal died, and diffuse of single cynomolgus target organ toxicity inflammatory infiltration was administration monkey occurs. Observing the observed on organs and tissues, but related symptoms, the no target organ toxicity was shown impact on body regardless of clinical pathology or weight, food intake, histological analysis. It had no ophthalmoscope significant effect on body weight, examination, food intake, ophthalmoscope electrocardiogram, examination, electrocardiogram, hematology, clinical hematology, clinical biochemistry, biochemistry, urine, urine, organ weight. There was no organ weight; the significant abnormality in the gross maximum tolerated anatomy. dose MTD, and sufficient safety factor were provided, Toxicity i.v./ SD rat Observing clinical No animal died, and diffuse of (Once a cynomolgus pathology and inflammatory infiltration was repeated week, 4 monkey histology to determine observed on organs and tissues, but administration weeks) whether there is target no target organ toxicity was shown organ toxicity regardless of clinical pathology or NOAEL, observing histological analysis. There were no the effects on body symptoms related to nivolumab, weight, food intake, and it had no significant effect on ophthalmoscope body weight, food intake, examination, ophthalmoscope examination, electrocardiogram, electrocardiogram, hematology, hematology, clinical clinical biochemistry, urine, and biochemistry, urine, organ weight. There was no organ weight; safty significant abnormality in the gross window was anatomy. calculated by immunogenicity (ADA (anti-drug antibody) analysis method), immunotoxicity studies (evaluation includes: hematology differential count of white blood cells (including macrophages), clinical chemistry (globulin and albumin: globulin ratio)), organ mass (thymus, spleen, lymph nodes) and histopathology (lymphatic organs and tissues) General i.v./ Central The main research The drug has no effect on the Safety Single nervous focus is on the central nervous system, Pharmacology dose system potential undesired cardiovascular system and Respiratory adverse effects on respiratory system. system physiological Cardiovascular functions when the system dosage of the drug is within or above the therapeutic range, that is, to observe the effects of the drug on the central nervous system, cardiovascular system and respiratory system. Local Vascular Rabbit Testing whether drugs No effect drug irritation have effects on blood safety test test vessels and blood and in vitro hemolysis test High Guinea Guinea pig Determining whether No sensitization sensitization pig there is sensitization test whole body active allergy test

[0143] Among them, the above experimental process and experimental conclusions are as follows:

[0144] toxicology experiment:

[0145] toxicity of single administration

[0146] SD rats and cynomolgus monkeys were observed for target organ toxicity. The related symptoms, such as the impact on body weight, food intake, ophthalmoscope examination, electrocardiogram, hematology, clinical biochemistry, urine and organ weight were observed. The maximum tolerated dose MTD and sufficient safety factor were provided. The results showed that there were no animal deaths, and diffuse inflammatory infiltration was observed on organs and tissues, but no target organ toxicity was shown in clinical pathology or histological analysis. It had no significant effect on body weight, food intake, ophthalmoscope examination, electrocardiogram, hematology, clinical biochemistry, urine and organ weight. There was no significant abnormality in the gross anatomy.

[0147] Toxicity of repeated administration: SD rats and cynomolgus monkeys were injected with the drug intravenously once a week for 4 consecutive weeks. The clinical pathology and histology were observed to determine whether there was target organ toxicity NOAEL. The impact on weight, food intake, ophthalmoscope examination, electrocardiogram, hematology, clinical biochemistry, urine and organ weight were observed. Safety window was calculated by immunogenicity (ADA (anti-drug antibody) analysis method), immunotoxicity studies (evaluation includes: hematology differential count of white blood cells (including macrophages), clinical chemistry (globulin and albumin: globulin ratio)), organ mass (thymus, spleen, lymph nodes) and histopathology (lymphatic organs and tissues). The results showed that no animals died, and diffuse inflammatory infiltration was observed on organs and tissues, but no target organ toxicity was shown regardless of clinical pathology or histological analysis. There were no symptoms related to nivolumab, and it had no significant effect on body weight, food intake, ophthalmoscope examination, electrocardiogram, hematology, clinical biochemistry, urine, and organ weight. There was no significant abnormality in the gross anatomy.

[0148] General safety pharmacology: SD rats were injected with the drug intravenously in single administration. The effects of the drug on the central nervous system, cardiovascular system and respiratory system were observed. The results showed that the drug had no effect on the central nervous system, cardiovascular system and respiratory system.

[0149] Local administration safety test (vascular irritation test and in vitro hemolysis test): New Zealand white rabbits were injected with the drug intravenously to test whether the drug had effects on blood vessels and blood. The results showed that the drug had no effect on blood vessels and blood.

[0150] High sensitization test (whole body active allergy test in guinea pigs): guinea pigs were injected with the drug intravenously in single administration to observe whether the drug had sensitization. The results showed that the drug had no sensitization.

[0151] Reference throughout this specification to “an embodiment”, “some embodiments”, “one embodiment”, “another example”, “an example”, “a specific example” or “some examples” means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. Thus, the appearances of the phrases such as “in some embodiments”, “in one embodiment”, “in an embodiment”, “in another example”, “in an example”, “in a specific example” or “in some examples” in various places throughout this specification are not necessarily referring to the same embodiment or example of the present disclosure. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples. In addition, without any contradiction, those skilled in the art may combine different embodiments or examples and features of the different embodiments or examples described in this specification.

[0152] Although explanatory embodiments have been shown and described, it would be appreciated by those skilled in the art that the above embodiments cannot be construed to limit the present disclosure, and changes, alternatives, and modifications can be made in the embodiments without departing from spirit, principles and scope of the present disclosure.