Antibodies against cd138 and uses thereof

Abstract

The application provides an antibody against CD138 and application thereof, the antibody comprises CDR sequences selected from at least one of the following or amino acid sequences with at least 95% identity: heavy chain variable region CDR sequences: SEQ ID NO: 1-3, light chain variable region CDR sequences: SEQ IN NO: 4-6. The antibody of the embodiment of the application can be combined with CD138, and can effectively treat and / or prevent CD138-mediated related diseases.

Description

Technical Field

[0001] This invention relates to the field of biomedicine, specifically to an anti-CD138 antibody and its application. Background Technology

[0002] Oncology is the second leading cause of death worldwide. Currently, approximately 10 monoclonal antibodies targeting tumor antigens are available globally, such as rituximab (targeting CD20), trastuzumab (targeting HER2), bevacizumab (targeting VEGF), and cetuximab (targeting EGFR). There are currently no marketed drugs targeting the CD138 molecule.

[0003] CD138, also known as Syndecan-1, is commonly expressed on epithelial cells and leukocytes. The Syndecan family consists of four members, all of which contain an intracellular C-terminus, a transmembrane region, and an extracellular N-terminus. These molecules have numerous polysaccharide branches in their extracellular region. The CD138 protein, containing 288 amino acids, is the second longest protein in the Syndecan family.

[0004] CD138 expression is abnormal in most tumors and other epithelial malignancies; for example, elevated CD138 expression is observed in over 60% of pathological samples from bladder cancer patients. Some studies have also shown that high CD138 expression in breast cancer patients is associated with poor prognosis. Furthermore, CD138 expression can be detected in the tumor epithelium and stromal cells of some ovarian cancer patients, but is not expressed in normal ovarian biopsy samples. CD138 expression is associated with functions such as invasive growth and metastatic tendency of tumor cells. These clinical results also suggest that CD138 could be a good target for clinical treatment.

[0005] Currently, murine antibodies or chimeric antibodies (such as BB4) targeting CD138 are used in clinical research. However, due to immunogenicity issues, these antibodies are easily recognized and eliminated by the human immune system. Meanwhile, for non-clinical research purposes, the ability to bind to monkey CD138 is also a factor in antibody selection. The previously known antibody (BT062) cannot bind to monkey CD138, and this antibody needs to be conjugated to a toxin to achieve its tumor-killing effect.

[0006] Therefore, further research is needed to develop a more effective and safer antibody drug targeting CD138. Summary of the Invention

[0007] This application is based on the inventor's discovery of the following problems and facts:

[0008] CD138 protein is upregulated in various tumor tissues, and its expression is related to functions such as invasive growth and metastatic tendency of tumor cells. Currently, murine antibodies or chimeric antibodies (such as BB4) targeting CD138 are used in clinical research, but these antibodies still have the problem of high immunogenicity. At the same time, due to the need for non-clinical research, the ability to bind to monkey CD138 is also a factor to consider when selecting antibodies.

[0009] The inventors of this application have successfully screened a murine anti-CD138 monoclonal antibody that exhibits high binding activity to human or monkey CD138 protein. Furthermore, the inventors mutated the post-translational modification (PTM) site of the aforementioned monoclonal antibody and humanized the constant region of the resulting murine antibody while retaining the CDR of the murine anti-CD138 monoclonal antibody to obtain a chimeric antibody. Further, the inventors humanized the framework region of the light chain variable region or heavy chain variable region of the chimeric antibody to obtain a fully humanized anti-CD138 antibody. This humanized antibody not only specifically targets and binds to both human and monkey CD138 proteins but also exhibits low immunogenicity, effectively treating and / or preventing CD138-mediated diseases such as tumors.

[0010] Therefore, in a first aspect, the present invention provides an antibody or antigen-binding fragment. According to embodiments of the invention, it 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 sequence: DYTIH (SEQ ID NO:1), WFYPGSDNIKYNEKFKD (SEQ ID NO:2), HERGYSTPGDV (SEQ ID NO:3); light chain variable region CDR sequence: RSX1QSLLHSNX2NTYLH (SEQ ID NO:4), RVSNRFS (SEQ ID NO:5), SQSSRIPWT (SEQ ID NO:6), wherein X1 is selected from N or Q, and X2 is selected from G or A. The antibody or antigen-binding fragment according to embodiments of the present invention can bind to human or monkey CD138 protein, effectively treating or preventing CD138-mediated diseases, and has higher safety.

[0011] In a second aspect, the present invention provides a nucleic acid molecule. According to embodiments of the present invention, the nucleic acid molecule encodes the antibody or antigen-binding fragment described in the first aspect. The antibody or antigen-binding fragment encoded by the nucleic acid molecule according to embodiments of the present invention can bind to human or monkey CD138 protein, effectively treating or preventing CD138-mediated diseases, and has higher safety.

[0012] In a third aspect, the present invention provides an expression vector. According to embodiments of the invention, the expression vector carries the nucleic acid molecule described in the second aspect. The expression vector may include an optional control sequence operatively linked to the nucleic acid molecule. The control sequence is one or more control sequences that direct the expression of the nucleic acid molecule in a host. The expression vector proposed in the embodiments of the present invention can efficiently and massively express the antibody or antigen-binding fragment in suitable host cells.

[0013] In a fourth aspect, the present invention provides a method for preparing the antibody or antigen-binding fragment described in the first aspect. According to embodiments of the invention, the method includes: introducing the expression vector described in the third aspect into cells; culturing the cells under conditions suitable for protein expression and secretion to obtain the antibody or antigen-binding fragment. The method proposed in the embodiments of the present invention can effectively obtain large quantities of the antibody or antigen-binding fragment in vitro.

[0014] In a fifth aspect, the present invention provides a recombinant cell. According to embodiments of the invention, the recombinant cell carries the nucleic acid described in the second aspect, or the expression vector described in the third aspect, or is capable of expressing the antibody or antigen-binding fragment described in the first aspect. The recombinant cell is obtained by transfection or transformation of the expression vector. According to some specific embodiments of the invention, the recombinant cell can efficiently and extensively express the aforementioned antibody or antigen-binding fragment under suitable conditions.

[0015] In a sixth aspect, the present invention provides an immunoconjugate. According to embodiments of the invention, the immunoconjugate comprises the antibody or antigen-binding fragment described in the first aspect, and a therapeutic agent. As previously stated, the antibody or antigen-binding fragment of the embodiments of the present invention can effectively bind to CD138 proteins, such as the CD138 protein on the surface of tumor cells. Therefore, the immunoconjugate containing the antibody or antigen-binding fragment can also bind to the CD138 protein in humans or monkeys, and the immunoconjugate has good preventive and / or therapeutic effects against CD138-mediated diseases.

[0016] In a seventh aspect, the present invention provides a composition. According to embodiments of the invention, it comprises the antibodies, nucleic acid molecules, expression vectors, or recombinant cells described above. As previously stated, the antibodies or antigen-binding fragments of the embodiments of the present invention can effectively bind to human or monkey CD138 protein; therefore, compositions containing the above substances can also effectively bind to human or monkey CD138 protein, exhibiting good preventive and / or therapeutic effects against CD138-mediated diseases.

[0017] In an eighth aspect, the present invention provides a medicament. According to embodiments of the present invention, the medicament comprises the antibody nucleic acid molecule, expression vector, recombinant cell, or composition described above. As previously stated, the antibody or antigen-binding fragment of the embodiments of the present invention can effectively bind to human or monkey CD138 protein; therefore, a medicament containing the above-described substances can also effectively bind to human or monkey CD138 protein, exhibiting good preventive and / or therapeutic effects against CD138-mediated diseases.

[0018] In a ninth aspect, the present invention provides a kit for detecting CD138. According to embodiments of the present invention, the kit contains the aforementioned antibody or its antigen-binding fragment, a nucleic acid molecule, an expression vector, or recombinant cells. As previously described, the antibody or antigen-binding fragment of the embodiments of the present invention can effectively bind to human or monkey CD138 protein; therefore, the kit containing the antibody or antigen-binding fragment can effectively perform qualitative or quantitative detection of CD138 protein. The kit can be used for scientific research, such as for the qualitative or quantitative detection of VEGF and / or ANG-2 in biological samples, and can also be used to assess individual status, such as determining whether an individual's VEGF and / or ANG-2 levels are excessively high or low compared to normal levels after obtaining the individual's VEGF and / or ANG-2 levels. The biological samples can be cells, tissues, urine, feces, etc.

[0019] In a tenth aspect, the present invention provides the use of the aforementioned antibodies or antigen-binding fragments thereof, nucleic acid molecules, expression vectors, recombinant cells, or compositions in the preparation of a medicament for the prevention and / or treatment of CD138-related diseases. As previously stated, the antibodies or antigen-binding fragments of the embodiments of the present invention can effectively bind to human or monkey CD138 proteins. Therefore, medicaments containing the above-mentioned substances can also effectively bind to human or monkey CD138 proteins, exhibiting good preventive and / or therapeutic effects against CD138-mediated diseases.

[0020] In an eleventh aspect, the present invention proposes the use of the aforementioned antibody or antigen-binding fragment in the preparation of a reagent kit. According to an embodiment of the present invention, the reagent kit is used to detect CD138. As previously described, the antibody or antigen-binding fragment of the embodiments of the present invention can effectively bind to human or monkey CD138 protein. Therefore, the antibody or antigen-binding fragment can express substances that can be used to prepare a reagent kit for detecting human or monkey CD138 protein. The reagent kit can effectively perform qualitative or quantitative detection of CD138 protein. The reagent kit can be used for scientific research, such as qualitative or quantitative detection of CD138 in biological samples, and can also be used to assess individual status, such as determining whether an individual's CD138 level is too high or too low than normal after obtaining the individual's CD138 level.

[0021] The beneficial effects of this invention are:

[0022] 1) The mouse-derived anti-CD138 monoclonal antibody obtained in this invention has higher CD138 protein binding activity than existing CD138 monoclonal antibodies, and the CD138 protein includes human CD138 protein and monkey CD138 protein.

[0023] 2) The humanized antibody obtained by mutating the mouse anti-CD138 monoclonal antibody at the PTM site and humanizing it also has higher CD138 protein binding activity than the existing CD138 monoclonal antibody. The CD138 protein includes human CD138 protein and monkey CD138 protein. The humanized antibody has lower immunogenicity, higher safety and longer efficacy.

[0024] Additional aspects and advantages of the invention 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 practice of the invention. Attached Figure Description

[0025] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0026] Figure 1A The image shows the ELISA results of different concentrations of mouse CD138 antibody (47A11) binding to human CD138 protein according to an embodiment of the present invention.

[0027] Figure 1B Figure 1 shows the ELISA results of different concentrations of mouse CD138 antibody binding to cynomolgus CD138 protein according to an embodiment of the present invention.

[0028] Figure 2AThis is a graph showing the detection results of different concentrations of mouse CD138 antibody binding to NCI-H929 cells according to an embodiment of the present invention;

[0029] Figure 2B This is a graph showing the detection results of different concentrations of mouse CD138 antibody binding to PANC-1 cells according to an embodiment of the present invention;

[0030] Figure 2C The graph shows the detection results of different concentrations of mouse CD138 antibody binding to MDA-MB-231 cells according to an embodiment of the present invention.

[0031] Figure 2D This is a graph showing the detection results of different concentrations of mouse CD138 antibody binding to NCI-H929 cells according to an embodiment of the present invention;

[0032] Figure 2E The figure shows the detection results of different concentrations of mouse CD138 antibody combined with cynomolgus CHO-K1 cells overexpressing cynomolgus CD138 protein according to an embodiment of the present invention.

[0033] Figure 3 The image shows the ELISA detection results of humanized CD138 antibody (h47A11) binding to human CD138 protein and cynomolgus monkey CD138 protein according to an embodiment of the present invention.

[0034] Figure 4 This is a graph showing the detection results of humanized CD138 antibody (h47A11) binding to NCI-H929 cells according to an embodiment of the present invention.

[0035] Figure 5 The figure shows the results of humanized CD138 (h47A11) inhibiting the proliferation of MM.1S cells according to an embodiment of the present invention. Detailed Implementation

[0036] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0037] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Furthermore, in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0038] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0039] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0040] To facilitate understanding of this invention, certain technical and scientific terms are specifically defined below. Unless explicitly defined elsewhere in this document, all other technical and scientific terms used herein have the meaning commonly understood by one of ordinary skill in the art to which this invention pertains. Abbreviations for amino acid residues are the standard 3-letter and / or 1-letter codes used in the art to refer to one of the 20 commonly used L-amino acids.

[0041] The antibody or antigen-binding fragments described in this invention are typically prepared by biosynthetic methods. Based on the nucleotide sequence described in this invention, those skilled in the art can readily obtain the encoding nucleic acid of this invention using various known methods. These methods include, but are not limited to, PCR, artificial DNA synthesis, etc., and specific methods can be found in J. Sambrook, *Molecular Cloning: A Laboratory Manual*. As one embodiment of this invention, the encoding nucleic acid sequence of this invention can be constructed by synthesizing the nucleotide sequence in segments and then performing overlap extension PCR.

[0042] In this document, the term "mutant" or "variant" may refer to a molecule obtained by mutating one or more nucleotides or amino acids into any naturally occurring or engineered molecule.

[0043] The terms "complementarity-determining region" or "CDR" or "CDR sequence" refer to the amino acid sequence in an antibody responsible for antigen binding. For example, it typically includes amino acid residues near 23-34 (L1), 50-56 (L2), and 89-97 (L3) in the light chain variable region, and near 31-35B (H1), 50-65 (H2), and 95-102 (H3) in the heavy chain variable region (Kabat et al., Sequences of Proteins of Immunological Interest, 5th Ed. Public Health Service, National Institutes of Health). Health, Bethesda, MD. (1991)); and / or amino acid residues from “high-variable rings” (e.g., amino acid residues near 26-32 (L1), 50-52 (L2) and 91-96 (L3) in the light chain variable region, and amino acid residues near 26-32 (H1), 53-55 (H2) and 96-101 (H3) in the heavy chain variable region (Chothia and Lesk J.Mol.Biol.196:901-917 (1987)).

[0044] In this paper, the terms “identity,” “homology,” or “similarity” are used to describe the percentage of identical amino acids or nucleotides between two amino acid sequences or nucleic acid sequences relative to a reference sequence, determined by conventional methods, for example, see Ausubel et al., eds. (1995), Current Protocols in Molecular Biology, Chapter 19 (Greene Publishing and Wiley-Interscience, New York); and the ALIGN procedure (Dayhoff (1978), Atlas of Protein Sequence and Structure 5: Suppl. 3 (National Biomedical Research Institute)). Foundation, Washington, DC). There are many algorithms for aligning sequences and determining sequence identity, including: Needleman et al. (1970) J. Mol. Biol. 48: 443, a homology alignment algorithm; Smith et al. (1981) Adv. Appl. Math. 2: 482, a local homology algorithm; Pearson et al. (1988) Proc. Natl. Acad. Sci. 85: 2444, a similarity search method; and the Smith-Waterman algorithm (Meth. Mol. Biol). .70:173-187 (1997); and the BLASTP, BLASTN, and BLASTX algorithms (see Altschul et al. (1990) J.Mol.Biol. 215:403-410). Computer programs utilizing these algorithms are also available, including but not limited to: ALIGN or Megalign (DNASTAR) software, or WU-BLAST-2 (Altschul et al., Meth.Enzym., 266:460-480 (1996)); or GAP, BESTFIT, BLAST Altschul et al., above, FASTA, and TFASTA, available in Genetics Computing Group (GCG) package, version 8, Madison, Wisconsin, USA; and CLUSTAL in the PC / Gene program provided by Intelligenetics, Mountain View, California.

[0045] Without substantially affecting antibody activity (retaining at least 95% of the activity), those skilled in the art can substitute, add, and / or delete one or more (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 or more) amino acids in the sequences of the present invention to obtain variants of the antibody or its functional fragments. These are all considered to be included within the scope of protection of the present invention. For example, amino acids with similar properties can be substituted in the variable region. The variant sequences of the present invention can have at least 80%, 85%, 90%, 95%, 96%, 97%, 98%, or 99% identity (or homology) with the reference sequence. Sequence identity described in the present invention can be measured using sequence analysis software, such as the computer program BLAST using default parameters, especially BLASTP or TBLASTN. The amino acid sequences described in the present invention are shown in N-terminus to C-terminus arrangement.

[0046] As previously described, the antibodies of the present invention may be full-length (e.g., IgG1 or IgG4 antibodies) or may contain only their functional fragments (e.g., Fab, F(ab')2, or scFv fragments), or may be modified to affect function. The present invention includes anti-CD138 antibodies with modified glycosylation patterns. In some applications, modification to remove undesirable glycosylation sites may be useful, or to antibodies lacking a fucose moiety on the oligosaccharide chain to, for example, enhance antibody-dependent cytotoxicity (ADCC) function. In other applications, galactosylation modification may be performed to alter complement-dependent cytotoxicity (CDC).

[0047] As used herein, the term "functional fragment" specifically refers to antibody fragments such as CDR transplantation antibodies, Fab, Fab', F(ab')2, Fv, or scFv, biantibodies, linear antibodies, single-chain antibody molecules, or diabody, or any fragment that should be able to increase its half-life through chemical modification or incorporation into liposomes, such as the addition of poly(alkylene) glycols, like polyethylene glycol ("PEGylated, PEGylated") (a PEGylated fragment referred to as Fv-PEG, scFv-PEG, Fab-PEG, F(ab')2-PEG, or Fab'-PEG) ("PEG" stands for polyethylene glycol), which have CD138 binding activity. Preferably, the functional fragment will consist of or contain a portion of the heavy chain variable region or light chain variable region of its source antibody, the portion of which is sufficient to retain the same binding specificity and sufficient affinity as its source antibody, preferably at least 1 / 100 of the affinity for CD138, and more preferably at least 1 / 10. This functional fragment will contain at least 3 amino acids, preferably 5, 10, 15, 25, 50, and 100 consecutive amino acids from the antibody sequence from which it is derived.

[0048] In this invention, unless otherwise stated, the term "antigen-binding fragment" as used generally refers to an antigen-binding antibody fragment, which may include a portion of a complete antibody, typically an antigen-binding region or a variable region, such as, for example, CDR transplanted antibodies, Fab, Fab', F(ab')2, Fv or scFv, biantibodies, linear antibodies, single-chain antibody molecules, etc.

[0049] In this paper, the term "CDR-transplanted antibody" refers to the transplantation of the CDR of a monoclonal antibody from one species into the variable region of an antibody from another species. For example, the CDR of a murine monoclonal antibody can be transplanted into the variable region of a human antibody to replace the human antibody's CDR, thereby giving the human antibody the antigen-binding specificity of the murine monoclonal antibody while reducing its heterologous nature.

[0050] In this article, the term "Fab antibody" generally refers to an antibody containing only Fab molecules, which consists of the VH and CH1 of the heavy chain and the complete light chain, linked by a disulfide bond.

[0051] In this paper, the term “single-domain antibody” (nanobody or VHH antibody), which was originally described as an antigen-binding immunoglobulin (variable) domain of “heavy chain antibody” (i.e., “antibody lacking light chain”) (Hamers-Casterman C, Atarhouch T, Muyldermans S, Robinson G, Hamers C, Songa EB, Bendahman N, Hamers R.: “Naturallyoccurring antibodies devoid of light chains”; Nature 363, 446-448 (1993)), contains only the heavy chain variable region (VH) and the conventional CH2 and CH3 regions, which bind specifically to the antigen through the heavy chain variable region.

[0052] In this article, the term "Fv antibody" generally refers to an antibody composed only of a light chain variable region (VL) and a heavy chain variable region (VH) linked by non-covalent bonds. It is the smallest functional fragment of an antibody that retains the complete antigen-binding site.

[0053] In one aspect of the invention, an antibody or antigen-binding fragment is provided, comprising 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 sequence: DYTIH (SEQ ID NO:1), WFYPGSDNIKYNEKFKD (SEQ ID NO:2), HERGYSTPGDV (SEQ ID NO:3); light chain variable region CDR sequence: RSX1QSLLHSNX2NTYLH (SEQ ID NO:4), RVSNRFS (SEQ ID NO:5), SQSSRIPWT (SEQ ID NO:6), wherein X1 is selected from N or Q, and X2 is selected from G or A. The antibody or antigen-binding fragment according to embodiments of the invention can bind to human or monkey CD138 protein, effectively treating or preventing CD138-mediated diseases, and has higher safety.

[0054] According to some specific embodiments of the present invention, the above-mentioned antibody or antigen-binding fragment may further include at least one of the following additional technical features:

[0055] According to some specific embodiments of the present invention, the heavy chain variable regions CDR1, CDR2, and CDR3 sequences are shown as amino acid sequences as in SEQ ID NO:1, 2, and 3 or having at least 95% identity with SEQ ID NO:1, 2, and 3, respectively; and / or light chain variable regions CDR1, CDR2, and CDR3 sequences are shown as in SEQ ID NO:4, 5, and 6 or having at least 95% identity with SEQ ID NO:4, 5, and 6, respectively.

[0056] According to some specific embodiments of the present invention, the CDR1 sequence of the heavy chain variable region as shown in SEQ ID NO:1, the CDR2 sequence of the heavy chain variable region as shown in SEQ ID NO:2, the CDR3 sequence of the heavy chain variable region as shown in SEQ ID NO:3, the CDR1 sequence of the light chain variable region as shown in SEQ ID NO:4, the CDR2 sequence of the light chain variable region as shown in SEQ ID NO:5, and the CDR3 sequence of the light chain variable region as shown in SEQ ID NO:6.

[0057] According to some specific embodiments of the present invention, the CDR1 sequence of the heavy chain variable region as shown in SEQ ID NO:1, the CDR2 sequence of the heavy chain variable region as shown in SEQ ID NO:2, the CDR3 sequence of the heavy chain variable region as shown in SEQ ID NO:3, the CDR1 sequence of the light chain variable region as shown in SEQ ID NO:7, the CDR2 sequence of the light chain variable region as shown in SEQ ID NO:5, and the CDR3 sequence of the light chain variable region as shown in SEQ ID NO:6.

[0058] According to some specific embodiments of the present invention, the CDR1 sequence of the heavy chain variable region as shown in SEQ ID NO:1, the CDR2 sequence of the heavy chain variable region as shown in SEQ ID NO:2, the CDR3 sequence of the heavy chain variable region as shown in SEQ ID NO:3, the CDR1 sequence of the light chain variable region as shown in SEQ ID NO:8, the CDR2 sequence of the light chain variable region as shown in SEQ ID NO:5, and the CDR3 sequence of the light chain variable region as shown in SEQ ID NO:6.

[0059] According to some specific embodiments of the present invention, it includes at least one of a heavy chain FR region and a light chain FR region.

[0060] According to some specific embodiments of the present invention, at least a portion of at least one of the heavy chain FR region and the light chain FR region is derived from at least one of human antibodies, primate antibodies and mouse antibodies or mutants thereof.

[0061] According to some specific embodiments of the present invention, at least one of the following is included: at least one of the heavy chain frame region HFR1, HFR2, HFR3 and HFR4 sequences as shown in SEQ ID NO:9-12; at least one of the heavy chain frame region HFR1, HFR2, HFR3 and HFR4 sequences as shown in SEQ ID NO:17-20; at least one of the light chain frame region LFR1, LFR2, LFR3 and LFR4 sequences as shown in SEQ ID NO:13-16; and at least one of the light chain frame region LFR1, LFR2, LFR3 and LFR4 sequences as shown in SEQ ID NO:21-24.

[0062] According to some specific embodiments of the present invention, the sequence includes at least one of the heavy chain frame regions HFR1, HFR2, HFR3 and HFR4 as shown in SEQ ID NO:9-12; at least one of the light chain frame regions LFR1, LFR2, LFR3 and LFR4 as shown in SEQ ID NO:13-16; or at least one of the heavy chain frame regions HFR1, HFR2, HFR3 and HFR4 as shown in SEQ ID NO:17-20; or at least one of the light chain frame regions LFR1, LFR2, LFR3 and LFR4 as shown in SEQ ID NO:21-24.

[0063] According to some specific embodiments of the present invention, it includes: a heavy chain variable region as shown in SEQ ID NO:25 or SEQ ID NO:27; and / or a light chain variable region as shown in SEQ ID NO:26, SEQ ID NO:28 or SEQ ID NO:2843.

[0064] According to some specific embodiments of the present invention, it includes: 1) a heavy chain variable region as shown in SEQ ID NO:25, and a light chain variable region as shown in SEQ ID NO:26 or 43; or 2) a heavy chain variable region as shown in SEQ ID NO:27, and a light chain variable region as shown in SEQ ID NO:28.

[0065] According to some specific embodiments of the present invention, the antibody or antigen-binding fragment contains at least one of a heavy chain constant region and a light chain constant region, and at least a portion of at least one of the heavy chain constant region and the light chain constant region is derived from at least one of a human antibody, a primate antibody, a mouse antibody, or a mutant thereof.

[0066] According to some specific embodiments of the present invention, both the light chain constant region and the heavy chain constant region are derived from mouse IgG antibodies or their mutants, or human IgG antibodies or their mutants.

[0067] According to some specific embodiments of the present invention, both the light chain constant region and the heavy chain constant region are derived from mouse IgG1 antibody or its mutant or human IgG1 antibody or its mutant.

[0068] According to some specific embodiments of the present invention, the antibody has a heavy chain constant region of the amino acid sequence as shown in SEQ ID NO:29 or 31 and / or a light chain constant region of the amino acid sequence as shown in SEQ ID NO:30 or 32.

[0069] According to some specific embodiments of the present invention, a heavy chain having the amino acid sequence shown in any one of SEQ ID NO:33 and 35 and a light chain having the amino acid sequence shown in any one of SEQ ID NO:34, 36 and 44 are used. According to some specific embodiments of the present invention, a murine anti-CD138 antibody without PTM site mutation consists of a heavy chain having the amino acid sequence shown in SEQ ID NO:33 and a light chain having the amino acid sequence shown in SEQ ID NO:34; a murine anti-CD138 antibody with PTM site mutation consists of a heavy chain having the amino acid sequence shown in SEQ ID NO:33 and a light chain having the amino acid sequence shown in SEQ ID NO:44; a humanized anti-CD138 antibody having the PTM site mutation consists of a heavy chain having the amino acid sequence shown in SEQ ID NO:35 and a light chain having the amino acid sequence shown in SEQ ID NO:36.

[0070] According to some specific embodiments of the present invention, the antibody or antigen-binding fragment is at least one of monoclonal antibody, polyclonal antibody, Fv, single-chain antibody, Fab, single-domain antibody, and minimum recognition unit.

[0071] According to some specific embodiments of the present invention, the antibody or its antigen-binding fragment is capable of binding to the amino acid sequence shown in SEQ ID NO:37 or 38.

[0072] The nucleic acids of the heavy and / or light chains encoding the antibodies or antigen-binding fragments of the present invention are within the scope of the present invention. Based on the amino acid sequences of the heavy and / or light chains, those skilled in the art can readily obtain the corresponding nucleic acid sequences.

[0073] Therefore, in another aspect of the present invention, a nucleic acid molecule is provided that encodes the antibody or antigen-binding fragment described in the first aspect. According to some specific embodiments of the present invention, the antibody or antigen-binding fragment encoded by the nucleic acid molecule can bind to the human or monkey CD138 protein, effectively treating or preventing CD138-mediated diseases, and exhibiting higher safety.

[0074] According to some specific embodiments of the present invention, the above-mentioned nucleic acid molecule may further include at least one of the following additional technical features:

[0075] According to some specific embodiments of the present invention, the nucleic acid molecule is DNA.

[0076] According to some specific embodiments of the present invention, the nucleic acid molecule has a nucleotide sequence as shown in any one of SEQ ID NO:39, 40, and 45-46. According to some specific embodiments of the present invention, the nucleotide sequence encoding a murine CD138 antibody without PTM site mutation consists of the nucleotide sequence encoding its heavy chain shown in SEQ ID NO:46 and the nucleotide sequence encoding its light chain shown in SEQ ID NO:47; the nucleotide sequence encoding a murine CD138 antibody with PTM site mutation consists of the nucleotide sequence encoding its heavy chain shown in SEQ ID NO:46 and the nucleotide sequence encoding its light chain shown in SEQ ID NO:45; and the nucleotide sequence encoding a humanized CD138 antibody consists of the nucleotide sequence encoding its heavy chain shown in SEQ ID NO:39 and the nucleotide sequence encoding its light chain shown in SEQ ID NO:40.

[0077] It should be noted that those skilled in the art should understand that the nucleic acids mentioned in this specification and claims actually include any one or both of the complementary double strands. For convenience, although only one strand is given in most cases in this specification and claims, the other complementary strand is actually disclosed as well. In addition, the nucleic acid sequences in this application include DNA or RNA forms; disclosure of one means that the other is also disclosed.

[0078] In another aspect, the present invention provides an expression vector carrying the aforementioned nucleic acid molecule. The expression vector may include an optional control sequence operatively linked to the nucleic acid molecule. The control sequence may be one or more control sequences that direct the expression of the nucleic acid molecule in a host. The expression vector proposed in this embodiment of the invention can efficiently and massively express the antibody or antigen-binding fragment in suitable host cells.

[0079] In this article, "operably ligated" refers to ligating a foreign gene to a vector so that the control elements within the vector, such as transcriptional and translational control sequences, can perform their intended functions of regulating the transcription and translation of the foreign gene. When ligating the aforementioned nucleic acid molecules to a vector, the nucleic acid molecules can be directly or indirectly linked to the control elements on the vector, as long as these control elements can control the translation and expression of the nucleic acid molecules. These control elements can be directly derived from the vector itself or be exogenous, i.e., not derived from the vector itself. Those skilled in the art will understand that nucleic acid molecules used to encode antibody or antigen-binding fragments can be independently inserted into different vectors, but commonly they are inserted into the same vector. Commonly used vectors include plasmids, bacteriophages, etc., such as the Plasmid-X plasmid.

[0080] In one aspect of the invention, a method for preparing the aforementioned antibody or antigen-binding fragment is provided, comprising: introducing the aforementioned expression vector into cells; and culturing the cells under conditions suitable for protein expression and secretion to obtain the antibody or antigen-binding fragment. The method proposed according to some specific embodiments of the invention can effectively obtain large quantities of the antibody or antigen-binding fragment in vitro.

[0081] According to some specific embodiments of the present invention, the above-described method for preparing the antibody or antigen-binding fragment may further include at least one of the following additional technical features:

[0082] According to some specific embodiments of the present invention, the cells are not particularly limited, and either prokaryotic cells or eukaryotic cells can be used.

[0083] According to some specific embodiments of the present invention, the cells are eukaryotic cells.

[0084] According to some specific embodiments of the present invention, the eukaryotic cells are mammalian cells. According to some specific embodiments of the present invention, when the cells are eukaryotic cells, such as mammalian cells, the expression efficiency of the recombinant antibody is higher.

[0085] In another aspect, the present invention provides a recombinant cell that expresses the aforementioned nucleic acid, or expression vector, or the aforementioned antibody or antigen-binding fragment. The recombinant cell is obtained by transfecting or transforming the expression vector. According to some specific embodiments of the present invention, the recombinant cell can efficiently and extensively express the aforementioned antibody or antigen-binding fragment under suitable conditions.

[0086] It should be noted that the recombinant cells described in this invention are not particularly limited and can be prokaryotic cells, eukaryotic cells, or bacteriophages. The prokaryotic cells can be Escherichia coli, Bacillus subtilis, Streptomyces, or Proteus mirabilis, etc. The eukaryotic cells include fungi such as Pichia pastoris, Saccharomyces cerevisiae, Schizosoma, and Trichoderma; insect cells such as armyworms; plant cells such as tobacco; and mammalian cells such as BHK cells, CHO cells, COS cells, and myeloma cells. In some embodiments, the recombinant cells described in this invention are preferably mammalian cells, including BHK cells, CHO cells, NSO cells, or COS cells, and do not include animal germ cells, fertilized eggs, or embryonic stem cells.

[0087] It should be noted that the "suitable conditions" mentioned in this application refer to conditions suitable for the expression of the antibody or antigen-binding fragment described in this application. Those skilled in the art will readily understand that suitable conditions for antibody or antigen-binding fragment expression include, but are not limited to, suitable transformation or transfection methods, suitable transformation or transfection conditions, healthy host cell state, suitable host cell density, suitable cell culture environment, and suitable cell culture time. The term "suitable conditions" is not particularly limited, and those skilled in the art can optimize the optimal conditions for antibody or antigen-binding fragment expression based on the specific environment of their laboratory.

[0088] In another aspect, the present invention provides an immunoconjugate comprising the aforementioned antibody or antigen-binding fragment and a therapeutic agent. As previously described, the antibody or antigen-binding fragment of the embodiments of the present invention can effectively bind to the CD138 protein and block the binding of the CD138 protein to its receptor. Therefore, the immunoconjugate containing the antibody or antigen-binding fragment can also bind to the CD138 protein in humans or monkeys, and the immunoconjugate has good preventive and / or therapeutic effects on CD138-mediated diseases.

[0089] In one aspect of the invention, a composition is provided comprising the aforementioned antibody, nucleic acid molecule, expression vector, or recombinant cell. As previously described, the antibody or antigen-binding fragment of some specific embodiments of the present invention can effectively bind to human or monkey CD138 protein and effectively inhibit the proliferation of tumor cells. Therefore, compositions containing the above substances can also effectively bind to human or monkey CD138 protein, exhibiting good preventive and / or therapeutic effects against CD138-mediated diseases. The type of composition is not particularly limited and can be a food composition or a pharmaceutical composition.

[0090] The compositions of the present invention can also be administered in combination with each other or in combination with one or more other therapeutic compounds, for example, in combination with a chemotherapeutic agent. Therefore, the compositions may also contain a chemotherapeutic agent. The antibodies or antigen-binding fragments thereof, or immunoconjugates of the present invention can also be combined with a second therapeutic agent, exemplary agents of which include, but are not limited to, other agents that inhibit CD138 activity (including other antibodies or antigen-binding fragments thereof, peptide inhibitors, small molecule antagonists, etc.) and / or agents that interfere with upstream or downstream signal transduction of CD138.

[0091] It should be noted that the compositions include combinations that are separate in time and / or space, as long as they can work together to achieve the objectives of the invention. For example, the components contained in the composition may be administered to the subject as a whole or separately. When the components contained in the composition are administered to the subject separately, the individual components may be administered to the subject simultaneously or sequentially.

[0092] In another aspect, the present invention provides a medicament comprising the aforementioned antibody nucleic acid molecule, expression vector, recombinant cell, or composition. As previously described, the antibody or antigen-binding fragment of some specific embodiments of the present invention can effectively bind to human or monkey CD138 protein. Therefore, a medicament containing an effective amount of the antibody active ingredient or a series of substances thereof can also effectively bind to human or monkey CD138 protein, and the antibody or antigen-binding fragment has good preventive and / or therapeutic effects on CD138-mediated diseases.

[0093] According to some specific embodiments of the present invention, the above-mentioned drug may further include at least one of the following additional technical features:

[0094] According to some specific embodiments of the present invention, the drug may also include a pharmaceutically acceptable carrier.

[0095] As used herein, the term “effective amount” or “effective dose” means an amount that is functional or active in humans and / or animals and is acceptable to humans and / or animals.

[0096] The effective amount of the antibody or antigen-binding fragment described in this invention can vary depending on the administration method and the severity of the disease to be treated. A preferred effective amount can be determined by those skilled in the art based on various factors (e.g., through clinical trials). These factors include, but are not limited to: pharmacokinetic parameters of the active ingredient, such as bioavailability, metabolism, and half-life; the severity of the disease to be treated, the patient's weight, the patient's immune status, and the route of administration. For example, due to the urgency of the treatment condition, several separate doses may be administered daily, or the dose may be reduced proportionally.

[0097] As used herein, a "pharmaceuticalally acceptable" ingredient is a substance suitable for human and / or mammalian use without excessive adverse side effects (such as toxicity, irritation, and allergic reactions), i.e., a substance with a reasonable benefit / risk ratio. The term "pharmaceuticalally acceptable carrier" refers to a carrier used for the administration of therapeutic agents, including various excipients and diluents.

[0098] The medicament of this invention contains a safe and effective amount of the active ingredient of this invention and a pharmaceutically acceptable carrier. Such carriers include (but are not limited to): saline, buffer solutions, glucose, water, glycerol, ethanol, and combinations thereof. Generally, the pharmaceutical formulation should be matched with the route of administration, wherein the route of administration may be oral, nasal, intradermal, subcutaneous, intramuscular, intravenous, or intraperitoneal. The dosage forms of the medicament of this invention are injections, oral formulations (tablets, capsules, oral liquids), transdermal formulations, and sustained-release formulations. For example, it is prepared using physiological saline or an aqueous solution containing glucose and other excipients by conventional methods. The medicament is preferably manufactured under sterile conditions. The antibody or antigen-binding fragment can be administered by intravenous infusion or injection, or by intramuscular or subcutaneous injection.

[0099] Of course, the anti-CD138 antibody described in this article can also be made into a kit or part of other diagnostic reagents as needed.

[0100] In another aspect, the present invention provides a kit for detecting CD138, the kit containing the aforementioned antibody or its antigen-binding fragment, nucleic acid molecules, expression vectors, or recombinant cells. As previously described, the antibodies or antigen-binding fragments of some specific embodiments of the present invention can effectively bind to human or monkey CD138 protein; therefore, kits containing the aforementioned antibodies or antigen-binding fragments can effectively perform qualitative or quantitative detection of human or monkey CD138 protein. The kits provided by the present invention can be used, for example, in kits involving the detection of human or monkey CD138 by utilizing the specific binding properties of antibodies, such as immunoblotting and immunoprecipitation. These kits may contain any one or more of the following: antagonists, anti-CD138 antibodies, or pharmaceutical reference materials; protein purification columns; immunoglobulin affinity purification buffers; cell assay diluents; instructions or literature, etc. Anti-CD138 antibodies can be used for different types of diagnostic tests, such as detecting the presence of various diseases, drugs, toxins, or other proteins in vitro or in vivo. For example, they can be used to test for related diseases by detecting the serum or blood of a subject. Such related diseases can include CD138-related diseases, such as cancers, including at least one of multiple myeloma, lung cancer, gastric cancer, colorectal cancer, pancreatic cancer, breast cancer, and bladder cancer. Of course, the antibody or antigen-binding fragments provided herein can also be used for radioimmunoassay and radioimmunotherapy of the above-mentioned diseases, etc.

[0101] The kit may also include reagents commonly used for detecting CD138, such as coating solutions.

[0102] In another aspect, the present invention proposes the use of the aforementioned antibodies or their antigen-binding fragments, nucleic acid molecules, expression vectors, recombinant cells, or compositions in the preparation of pharmaceuticals for the prevention and / or treatment of CD138-related diseases. As previously stated, the antibodies or antigen-binding fragments of some specific embodiments of the present invention can effectively bind to human or monkey CD138 proteins. Therefore, pharmaceuticals containing the above-mentioned substances can also effectively bind to human or monkey CD138 proteins, exhibiting good preventive and / or therapeutic effects against CD138-mediated diseases.

[0103] According to some specific embodiments of the present invention, the use of the above-mentioned prepared drug may further include at least one of the following additional technical features:

[0104] According to some specific embodiments of the present invention, the CD138-related disease is cancer.

[0105] According to some specific embodiments of the present invention, the cancer includes at least one of multiple myeloma, lung cancer, gastric cancer, intestinal cancer, pancreatic cancer, breast cancer, and bladder cancer.

[0106] In another aspect of the invention, the invention proposes the use of the aforementioned antibody or antigen-binding fragments, nucleic acid molecules, expression vectors, or recombinant cells in the preparation of a kit for detecting CD138. As previously described, the antibody or antigen-binding fragments of some specific embodiments of the invention can effectively bind to human or monkey CD138 protein and block the binding of the CD138 protein to its receptor. Therefore, the antibody or antigen-binding fragments can be used to prepare a kit for detecting CD138 protein, which can effectively perform qualitative or quantitative detection of human or monkey CD138 protein.

[0107] This invention also relates to a method for preventing and / or treating CD138-related diseases, the method comprising administering to a subject an effective amount of at least one of the following: the aforementioned antibody or its antigen-binding fragment, a nucleic acid molecule, an expression vector, recombinant cells, an immunoconjugate, a composition, and a drug. As previously described, the antibody or antigen-binding fragment can effectively bind to the CD138 protein in humans or monkeys and effectively inhibit the proliferation of tumor cells; therefore, the method according to embodiments of the present invention can effectively prevent and / or treat CD138-mediated related diseases.

[0108] In another aspect of the invention, a method for diagnosing CD138-related diseases is proposed. According to embodiments of the invention, the method includes detecting CD138 in a test sample using at least one of the following: 1) the aforementioned antibody or antigen-binding fragment; 2) the aforementioned nucleic acid molecule; 3) the aforementioned expression vector; and 4) the aforementioned recombinant cells. Based on the detection results of CD138, the content of CD138 in the test sample is determined. The antibody or antigen-binding fragment, or nucleic acid molecule, expression vector, or antibody or antigen-binding fragment expressed by recombinant cells, proposed in this application can effectively bind to human or monkey CD138 protein. Therefore, the method described in this application can effectively detect the content of CD138 in test samples derived from test individuals and effectively diagnose CD138-related diseases.

[0109] According to some specific embodiments of the present invention, the above-described method for diagnosing CD138-related diseases may further include at least one of the following additional technical features:

[0110] According to some specific embodiments of the present invention, the requirement that the CD138 content in the test sample is not lower than the minimum standard for disease indicates that the test sample originates from a patient suffering from a CD138-related disease. The value of this minimum standard can be determined through comparative analysis and verification of the differences in CD138 content in test samples from a large number of individuals suffering from CD138-related diseases and a large number of healthy individuals.

[0111] According to some specific embodiments of the present invention, the sample to be tested includes at least one of the following: blood, tissue, cells, feces, and urine.

[0112] According to some specific embodiments of the present invention, the diseases related to angiogenesis include tumors.

[0113] According to some specific embodiments of the present invention, the tumor includes at least one of multiple myeloma, lung cancer, gastric cancer, intestinal cancer, pancreatic cancer, breast cancer, and bladder cancer.

[0114] In another aspect of the invention, a method for assessing the staging of CD138-related diseases is proposed. According to embodiments of the invention, the method includes detecting CD138 in a test sample using at least one of the following: 1) the aforementioned antibody or antigen-binding fragment; 2) the aforementioned nucleic acid molecule; 3) the aforementioned expression vector; and 4) the aforementioned recombinant cells. Based on the detection results of the CD138, the content of CD138 in the test sample is determined. The antibody or antigen-binding fragment, or nucleic acid molecule, expression vector, or antibody or antigen-binding fragment expressed by recombinant cells, proposed in this application can effectively bind to human or monkey CD138 protein. Therefore, the method described in this application can effectively detect the CD138 content in test samples derived from test individuals and assess the stage of CD138-induced angiogenesis-related diseases based on the CD138 content.

[0115] According to embodiments of the present invention, the method for assessing CD138-related disease staging described above may further include at least one of the following additional technical features:

[0116] According to embodiments of the present invention, a CD138 content in the test sample not lower than the minimum level for stage IV tumor disease indicates that the test sample originated from a patient with stage IV tumor disease; a CD138 content in the test sample between the levels for stage IV and stage III tumor disease indicates that the test sample originated from a patient with stage III tumor disease; a CD138 content in the test sample between the standard levels for stage III and stage II tumor disease indicates that the test sample originated from a patient with stage II tumor disease; and a CD138 content in the test sample between the standard levels for stage I and stage II tumor disease indicates that the test sample originated from a patient with stage I tumor disease. Those skilled in the art will understand that the CD138 levels for stage I, II, III, and IV tumor disease vary depending on the type of tumor. Determining the tumor stage can be achieved by comparing the CD138 content in the test sample with the standard level of CD138 for that tumor stage, or by comparing the CD138 content in the test sample with the CD138 content in samples from known diseased individuals or groups. The minimum levels for each stage can be determined by comparative analysis and verification of the differences in CD138 levels in test samples from a large number of individuals with CD138-related diseases and a large number of healthy individuals.

[0117] According to an embodiment of the present invention, the sample to be tested includes at least one of the following: blood, tissue, cells, feces, and urine.

[0118] According to an embodiment of the present invention, the CD138-related diseases include tumors.

[0119] According to embodiments of the present invention, the tumor includes at least one of multiple myeloma, lung cancer, gastric cancer, intestinal cancer, pancreatic cancer, breast cancer, and bladder cancer.

[0120] In another aspect, the present invention provides a method for assessing the prognosis of CD138-related diseases. According to embodiments of the invention, the method includes detecting CD138 in a test sample using at least one of the following: 1) the aforementioned antibody or antigen-binding fragment; 2) the aforementioned nucleic acid molecule; 3) the aforementioned expression vector; and 4) the aforementioned recombinant cells, and determining the CD138 content in the test sample based on the detection results. As mentioned earlier, CD138 protein is upregulated in various tumor tissues and has a significant impact on the invasive growth and metastatic tendency of tumors. After treatment, individuals with CD138-mediated diseases can have their prognosis effectively assessed by monitoring the CD138 content in their tissues or excretions, such as peripheral blood and urine. For example, the CD138 content in the body of the subject before and after treatment can be compared, or the CD138 content in the body of the subject after treatment can be compared with the CD138 level of normal or diseased individuals. The antibody or antigen-binding fragment, or nucleic acid molecule, expression vector, or antibody or antigen-binding fragment expressed by recombinant cells proposed in this application can effectively bind to CD138. Therefore, the method described in this application can effectively detect the CD138 content in the test sample derived from the test individual and assess the prognosis of CD138-related diseases based on the CD138 content.

[0121] According to embodiments of the present invention, the above-described method for assessing the prognosis of CD138-related diseases may further include at least one of the following additional technical features:

[0122] According to an embodiment of the present invention, the test sample is derived from a patient with CD138-related disease before or after treatment.

[0123] According to an embodiment of the present invention, the prognostic effect of CD138-related diseases is determined based on the CD138 content in the test sample of a patient with CD138-related diseases before or after treatment.

[0124] According to an embodiment of the present invention, a decrease in the CD138 content in the test sample of a patient with CD138-related disease after treatment is an indicator of a good prognosis for the patient.

[0125] According to an embodiment of the present invention, the sample to be tested includes at least one of the following: blood, tissue, cells, feces, and urine.

[0126] According to an embodiment of the present invention, the CD138-related diseases include tumors.

[0127] According to embodiments of the present invention, the tumor includes at least one of multiple myeloma, lung cancer, gastric cancer, intestinal cancer, pancreatic cancer, breast cancer, and bladder cancer.

[0128] In one aspect, the present invention proposes the use of the aforementioned antibody or antigen-binding fragment, nucleic acid molecule, expression vector, recombinant cell, composition, or drug in the treatment or prevention of CD138-related diseases. As previously stated, the antibody or antigen-binding fragment is capable of effectively binding to human or monkey CD138 protein, and can effectively treat or prevent CD138-mediated related diseases.

[0129] According to embodiments of the present invention, the above-described uses may further include at least one of the following additional technical features:

[0130] According to an embodiment of the present invention, the CD138-related diseases include tumors.

[0131] According to embodiments of the present invention, the tumor includes at least one of multiple myeloma, lung cancer, gastric cancer, intestinal cancer, pancreatic cancer, breast cancer, and bladder cancer.

[0132] In another aspect, this invention proposes the use of the aforementioned antibodies or antigen-binding fragments, nucleic acid molecules, expression vectors, or recombinant cells in diagnosing CD138-related diseases, assessing the staging of CD138-related diseases, or assessing the prognosis of CD138-related diseases. As previously stated, the antibodies or antigen-binding fragments, or nucleic acid molecules, expression vectors, or antibodies or antigen-binding fragments expressed by recombinant cells, proposed in this application can effectively bind to human or monkey CD138. Therefore, the method described in this application can effectively detect the CD138 content in test samples derived from test individuals and can effectively diagnose, stage, and assess the prognosis of CD138-related diseases.

[0133] According to embodiments of the present invention, the above-described uses may further include at least one of the following additional technical features:

[0134] According to an embodiment of the present invention, the CD138-related diseases include tumors.

[0135] According to embodiments of the present invention, the tumor includes at least one of multiple myeloma, lung cancer, gastric cancer, intestinal cancer, pancreatic cancer, breast cancer, and bladder cancer.

[0136] The term "subject" or "individual" in this invention generally refers to mammals, such as primates and / or rodents, particularly humans, monkeys, or rats.

[0137] The sequence descriptions involved in this invention are detailed in Table 1.

[0138] Table 1:

[0139]

[0140]

[0141]

[0142]

[0143]

[0144]

[0145]

[0146] The present invention will be described in detail below through examples. In the examples or test cases, experimental methods without specific conditions are performed under conventional conditions.

[0147] The present invention will be explained below with reference to embodiments. Those skilled in the art will understand that the following embodiments are for illustrative purposes only and should not be considered as limiting the scope of the invention. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in the field or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be obtained commercially.

[0148] Example 1: Construction of CHO-K1 cells overexpressing human and cynomolgus monkey CD138

[0149] HEK293T cells were seeded in T150 culture flasks and cultured in DMEM complete medium. After overnight culture, endotoxin-free psPAX2, pMD2.G, and pCDH-CMV-syndecan-1-IRES-puro vectors (pCDH-CMV-MCS-IRES-puro vectors with an inserted human CD138 protein coding sequence (SEQ ID NO:41) or cynomolgus monkey protein coding sequence (SEQ ID NO:42)) were added to 1.5 mL of Opti-MEM (Gibco, catalog number 31985070) medium at a ratio of 7:3:10, followed by 100 μL of Lipofectamine 3000 transfection reagent. 100 μL of Lipofectamine 3000 (thermo, catalog number L3000008) transfection reagent was then added to 1.5 mL of Opti-MEM medium and mixed thoroughly. DNA dilution buffer and liposome dilution buffer were mixed at a volume ratio of 1:1 and incubated at room temperature for 5-10 min. The mixture was then added to 293T cells, and the viral supernatant was harvested after 48 hours of culture. The viral supernatant was centrifuged at 2000g for 10 min at 4°C. The supernatant was collected, filtered through a 0.45μm filter, and then added to PEG8000 solution (Shanghai Sangon Biotech). The mixture was thoroughly mixed and incubated overnight at 4°C. Then, it was centrifuged at 2200g for 90 min. A white precipitate was observed at the bottom of the centrifuge tube; the virus was resuspended in sterile PBS buffer.

[0150] Polybrene (Sigma, TR-1003) (final concentration 8 μg / mL) was added to DME / F12 medium, mixed well, and then an appropriate amount of virus solution was added. 2E5 CHO-K1 cells were placed in a 24-well plate, virus-containing medium was added, and the plate was incubated for 8 hours before being replaced with fresh medium. After 48 hours of culture, the expression level of CD138 on the surface of CHO-K1 cells was detected by flow cytometry. Once a positive cell population appeared, a limiting dilution was performed (digestion and dilution to a density of 4 cells / mL), and the cells were seeded into 96-well plates at a density of 200 μL per well. After 2 weeks of culture until the cells clearly formed single cell clusters, the expression level of CD138 on the surface of each clone was detected by flow cytometry. All positive cells were considered CHO-K1 cells that overexpressed human CD138 protein (SEQ ID NO:37) or cynomolgus monkey CD138 protein (SEQ ID NO:38).

[0151] Example 2: Preparation of anti-human CD138 hybridoma monoclonal antibody

[0152] In this invention, the anti-human CD138 monoclonal antibody was generated by immunizing mice. Female, 6-week-old C57BL / 6 mice (Jiangsu Jicui Yaokang Biotechnology Co., Ltd.) were used as the immunogenic antigen. The immunogenic antigen was CHO-K1 cells overexpressing human CD138 obtained in Example 1, with 5E6 immune cells per mouse. The cells were pretreated with mitomycin C for 4 hours and then injected intraperitoneally into the mice. Immunization was repeated every two weeks after the initial immunization, for a total of 5 immunizations. Antibody titers were detected by ELISA using serum from the immunized mice, following standard procedures in the art.

[0153] Based on antibody titer results, mice with high serum antibody titers were selected for spleen cell fusion. 72 hours prior to fusion, the selected mice were immunized by intraperitoneal injection with 5E6 cells per mouse. Using an optimized PEG-mediated fusion procedure, spleen lymphocytes were fused with myeloma Sp2 / 0 cells (ATCC, CRL-8287) to obtain hybridoma cells. The fused hybridoma cells were resuspended in HAT complete medium (RPMI-1640 medium containing 20% ​​FBS, 1×HAT, and 1×OPI) and aliquoted into 96-well cell culture plates, incubated at 37°C and 5% CO2. On day 5 post-fusion, 50 μL of HAT complete medium was added per well. From day 7 to 8 post-fusion, the medium was completely replaced with HT complete medium (RPMI-1640 medium containing 20% ​​FBS, 1×HT, and 1×OPI), 200 μL per well, based on cell growth density.

[0154] On days 10-11 post-fusion, flow cytometry was performed to detect cell growth density. Positive wells were replaced with new medium, and the cells were promptly expanded to 24-well plates according to density. Cell lines transferred to 24-well plates were retested and then preserved for the first subcloning. Cells showing positive results in the first subcloning were preserved and subjected to a second subcloning. Cells showing positive results in the second subcloning were then preserved and subjected to protein expression. Subcloning and preservation were performed using standard techniques in the field. Antibodies were further prepared using serum-free cell culture, and the mouse antibodies were purified by protein G affinity chromatography for subsequent functional activity assays.

[0155] Example 3: Mouse CD138 Antibody ELISA Binding Assay

[0156] The ELISA assay was used to detect the binding characteristics of murine CD138 antibody 47A11. Human CD138 protein (ACRObiosystems, SY1-H5225) or cynomolgus monkey CD138 protein (Yiqiao Shenzhou, 90938-C02H) was diluted to 2 μg / mL with coating buffer (35 mM NaHCO3, 15 mM Na2CO3, pH 9.6), and 100 μL was added to each well of the ELISA plate and incubated overnight at 4°C. The plate was then washed three times with PBST (0.05% Tween 20-PBS, pH 7.2). 300 μL of blocking buffer (1% BSA, 0.05% Tween 20-PBS, pH 7.2) was added to the plate and incubated at room temperature for 2 h. The plate was then washed three more times with PBST. Add mouse antibody 47A11 or control antibody BT062 (WO2009080832) and mouse IgG antibody (purchased from Biolegend, catalog number 400153) to each well and incubate at room temperature for 1 hour. Wash three times with PBST. Add 100 μL of HRP-goat anti-mouse IgG secondary antibody (boster, catalog number BA1051) diluted with blocking buffer to each well and incubate at room temperature for 1 hour. Wash three times with PBST, add TMB to each well, and react at room temperature in the dark for 2-5 minutes. Terminate the reaction with 2M sulfuric acid in each well. Finally, read the OD450 value using a microplate reader. Figure 1A This indicates that the murine 47A11 antibody of the present invention can bind to human CD138. Figure 1B This indicates that the murine 47A11 antibody of the present invention can also bind to cynomolgus monkey CD138.

[0157] Example 4: Flow cytometry-based assay using mouse CD138 antibody

[0158] Multiple myeloma NCI-H929 cells, pancreatic cancer PANC-1 cells, breast cancer MDA-MB-231 cells, lung cancer NCI-H292 cells (purchased from Shanghai Cell Bank), or CHO-K1 cells overexpressing CD138 from cynomolgus monkeys obtained in Example 1 were diluted with PBS to a concentration of 2 × 10⁻⁶ cells. 6Cells were added at a rate of 100 μL / tube to a 1.5 mL EP tube, followed by 10 μL / tube of goat serum. The tube was then blocked at 4°C for 30 min. Gradient concentrations of CD138 antibody obtained in Example 2 were added, and the tube was incubated at 4°C for 30 min. 1 mL of PBS was added to the EP tube, and the tube was centrifuged at 3500 rpm for 5 min at 4°C. The supernatant was discarded, and the tube was washed once with PBS. After centrifugation, the supernatant was discarded again, and the cells were resuspended in 100 μL / tube of PBS. 0.1 μL / tube of Alexa 647-labeled goat anti-mouse antibody secondary antibody (Invitrogen) was added, and the tube was incubated at 4°C in the dark for 30 min. After incubation, the cells were washed twice with PBS, centrifuged, and the supernatant was discarded. The cells were resuspended in 200 μL / tube of PBS and analyzed by flow cytometry, using BT062 antibody as a control antibody. Figure 2A , 2B Experiments 2C, 2D, and 2E showed that the murine 47A11 antibody could bind to multiple myeloma NCI-H929 cells, pancreatic cancer PANC-1 cells, breast cancer MDA-MB-231 cells, lung cancer NCI-H292 cells, and CHO-K1 cells overexpressing cynomolgus monkey CD138, indicating that the murine CD138 antibody can bind to the CD138 protein on the cell surface.

[0159] Example 5 Hybridoma Sequencing

[0160] Using hybridomas of the 47A11 antibody screened through experiments in Examples 3 and 4, the total number of candidate hybridoma cells was cultured to 10. 6Cells were collected by centrifugation at 800 rpm for 10 minutes, and total RNA was extracted using the Trizol kit (Invitrogen). Using the total RNA as a template, a cDNA library was synthesized by reverse transcription (Invitrogen). The cDNA was then used as a template for PCR amplification of the corresponding variable region nucleic acid sequence of hybridoma cells. The primer sequences used in the PCR amplification reaction were complementary to the first frame region or signal peptide region and constant region of the antibody variable region (Larrick, JW, et al., (1990) Scand. J. Immunol., 32, 121 128 and Coloma, JJ et al., (1991) BioTechniques, 11, 152 156). PCR amplification was performed in a 50 μL reaction system, with the following components added: 2 μL of the cDNA, 5 μL of 10×PCR buffer, 2 μL (5 μM) of upstream and downstream primers, 2 μL of dNTPs, 1 μL of Taq enzyme (Takara, Ex Taq), and 38 μL of H2O. The mixture was pre-denatured at 95℃ for 5 min, followed by temperature cycling for PCR amplification. The reaction conditions were: denaturation at 94℃ for 30 s, annealing at 58℃ for 45 s, extension at 72℃ for 50 s, for a total of 32 cycles, followed by a final extension at 72℃ for 7 min. Sequencing of the amplified products yielded the heavy chain variable region (amino acid sequence as shown in SEQ ID NO:25) and light chain variable region sequences (amino acid sequence as shown in SEQ ID NO:26) of the mouse monoclonal antibody.

[0161] Example 6: Post-translational modification (PTM) site mutation of anti-human CD138 antibody

[0162] Post-translational modifications (PTMs) of antibodies refer to the modifications made to specific amino acids during antibody expression in eukaryotic cells. These modifications can play a crucial role in the function and characterization of antibodies. During antibody production, various physicochemical factors generate different PTM variants, such as glycosylation, oxidation, deamidation, and isomerization. These PTMs can cause changes in the physicochemical properties of antibodies, and may also reduce antibody stability and induce immunogenicity. The inventors analyzed the CDR sequence of the murine antibody 47A11 and found glycosylation and deamidation sites in the light chain CDR1 sequence (CDR1 in SEQ ID NO:7). Therefore, the inventors designed a mutant sequence for the light chain CDR1 (SEQ ID NO:8), and the mutated light chain variable region sequence is SEQ ID NO:43.

[0163] The inventors constructed a pTT5 vector carrying a light chain nucleotide sequence (SEQ ID NO:44) encoding the light chain variable region of a murine anti-human CD138 antibody with a PTM mutation and the human IgG1 light chain constant region, and a heavy chain nucleotide sequence (SEQ ID NO:46) encoding the heavy chain variable region and the IgG1 heavy chain constant region. They also constructed a pTT5 vector carrying a light chain nucleotide sequence (SEQ ID NO:47) encoding the light chain variable region of a murine anti-human CD138 antibody without the PTM mutation and the human IgG1 light chain constant region, and a heavy chain nucleotide sequence (SEQ ID NO:46) encoding the heavy chain variable region and the IgG1 heavy chain constant region. The pTT5 vectors were used to transiently transfect ExpiCHO-S cells (Gibco, catalog number A29127) to prepare PTM-mutated chimeric antibodies and original chimeric antibodies binding to the CD138 protein. One day before transfection, the ExpiCHO-S cells were adjusted to a cell density of (3–4) × 10⁻⁶ cells. 6 / mL, incubated overnight at 37℃, 8% CO2, with shaking at 120 rpm. On the day of transfection, cells grew to 7 × 10⁹ / mL. 6 –1×10 7 When the cell count is 10 cells / mL and the viability is greater than 95%, prepare for transfection. Dilute the cells to 6 × 10⁶ cells / mL using fresh, pre-warmed ExpiCHO medium (Gibco, catalog number A2910002). 6 / mL, then take the two plasmids containing anti-human CD138 antibodies, light chain and heavy chain, respectively, at a molar ratio of 2:1 and transfect them into ExpiCHO-S cells using ExpiFectamine CHO transfection reagent (Gibco, catalog number A29129). Incubate at 37℃, 8% CO2, and 120 rpm with shaking. 18-22 h post-transfection, immediately add ExpiFectamine CHO Enhancer and ExpiCHO Feed to the transfected cells, mix well, and incubate at 32℃, 5% CO2, and 120 rpm with shaking. On day 5 post-transfection, add another 8 mL of ExpiCHO Feed to the cells, mix well, and continue culturing. Observe cell count and cell viability changes daily. Harvest cells by centrifugation when cell viability drops below 80% or after 10-14 days of culture.

[0164] The expression supernatant from the centrifuged cells was filtered through a 0.22 μm filter membrane. Antibodies containing the Fc domain were captured from the expression supernatant using a Mabselect Prism A affinity chromatography column (GE, catalog number 17549854). After equilibrating the column with phosphate buffer (pH 7.2), the supernatant was passed through the affinity chromatography column and eluted with elution buffer (100 mM citric acid, pH 2.7). Finally, the elution was concentrated and replaced with PBS buffer. The purified antibody was identified by SDS-PAGE as having a purity of over 95%.

[0165] The affinity of the original 47A11 chimeric antibody and the PTM-mutated 47A11 chimeric antibody for human CD138 antigen was tested using BIACORE. The results are shown in Table 2, indicating that the PTM site mutation does not affect the binding of the 47A11 chimeric antibody to human CD138 antigen.

[0166] Table 2:

[0167]

[0168] Example 7: Humanization of Anti-human CD138 Monoclonal Antibody

[0169] Based on the chimeric antibody obtained in Example 5, by comparing the IMGT human antibody heavy and light chain variable region germline gene database and MOE software, heavy chain or light chain variable region germline genes with high homology to the murine antibody 47A11 were selected as templates. The CDRs of the murine antibody were then transplanted into the corresponding human templates, forming variable region sequences in the order FR1-CDR1-FR2-CDR2-FR3-CDR3-FR4. The amino acid residues were determined and annotated using the Kabat numbering system.

[0170] To maintain the conformation of the CDR region, residues at the VL and VH binding interfaces, residues close to the CDR and embedded inside the protein, and residues that directly interact with the CDR are reverse-mutated to ensure that the activity of the variable region is not affected.

[0171] The heavy chain variable region sequence of the humanized CD138 antibody 47A11 is shown in SEQ ID NO:27, and the light chain variable region sequence is shown in SEQ ID NO:28. Nucleotide sequences encoding the heavy chain of the humanized antibody (SEQ ID NO:39) and the light chain of the humanized antibody (SEQ ID NO:40) were recombined into the pTT5 plasmid using molecular biology techniques. Humanized 47A11 was produced and purified using the protein expression and purification protocol shown in Example 5, ultimately yielding humanized 47A11 antibodies (SEQ ID NO:35 and 36).

[0172] The affinity of the humanized 47A11 antibody to the human CD138 antigen was tested using BIACORE, and the results are shown in Table 3. The obtained humanized antibody has good affinity to the CD138 antigen.

[0173] Table 3:

[0174] Antibody ka(1 / Ms) kd(1 / s) KD(M) Humanized h47A11 2.30E+06 1.58E-04 6.87E-10

[0175] Example 8: Humanized CD138 antibody ELISA binding assay

[0176] The ELISA assay was used to detect the binding characteristics of humanized CD138 antibody 47A11. Human CD138 protein (ACRObiosystems, SY1-H5225) or cynomolgus monkey CD138 protein (Yiqiao Shenzhou, 90938-C02H) was diluted to 2 μg / mL with coating buffer (35 mM NaHCO3, 15 mM Na2CO3, pH 9.6), and 100 μL was added to each well of the ELISA plate and incubated overnight at 4°C. The plate was then washed three times with PBST (0.05% Tween 20-PBS, pH 7.2). 300 μL of blocking buffer (1% BSA, 0.05% Tween 20-PBS, pH 7.2) was added to the plate and incubated at room temperature for 2 h. The plate was then washed three more times with PBST. A gradient concentration of humanized anti-human CD138 antibody 47A11 was added to each well and incubated at room temperature for 1 h. The plate was then washed three more times with PBST. Add 100 μL of HRP-goat anti-human IgG (Fab-specific) secondary antibody (Sigma, A0293) diluted with blocking buffer to each well and incubate at room temperature for 1 hour. Wash three times with PBST, add TMB to each well, and incubate at room temperature in the dark for 2-5 minutes. Terminate the reaction with 2M sulfuric acid in each well. Finally, read the OD450 value using a microplate reader. Figure 3 The results show that the humanized 47A11 antibody of the present invention can bind to the CD138 antigen in humans and monkeys.

[0177] Example 9: Humanized CD138 Antibody Flow Cytometry Combination Experiment

[0178] Multiple myeloma NCI-H929 cells were diluted to 2 × 10⁻⁶ cells with PBS. 6 Add 100 μL of mouse serum to each 1.5 mL EP tube, and then add 10 μL of mouse serum. Block at 4°C for 30 min. Add a gradient concentration of humanized CD138 antibody 47A11 and incubate at 4°C for 30 min. Add 1 mL of PBS to the EP tube, centrifuge at 3500 rpm for 5 min at 4°C, discard the supernatant, and wash once with PBS. After centrifugation, discard the supernatant again, resuspend the cells in 100 μL of PBS, add 0.1 μL of Alexa 647-labeled mouse anti-human IgG Fc antibody secondary antibody (Biolegend), and incubate at 4°C in the dark for 30 min. Wash twice with PBS, centrifuge, and discard the supernatant. Resuspend the cells in 200 μL of PBS and analyze using flow cytometry. Figure 4 The results showed that the humanized 47A11 antibody could bind to multiple myeloma NCI-H929 cells.

[0179] Example 10: Humanized anti-human CD138 antibody inhibits tumor cell proliferation

[0180] Multiple myeloma MM.1S cells were diluted to 1×10⁻⁶ using culture medium. 5 100 μL of diluted multiple myeloma MM.1S cells were added to each well of a 96-well plate at a concentration of / mL. The gradient concentrations of humanized anti-human CD138 antibody obtained in Example 6 were added, and the plates were incubated at 37°C and 5% CO2 for 72 hours. Total cell detection reagent (Promega, G9290) was then added, and fluorescence values ​​were read using a multi-functional microplate reader to calculate the relative cell count. The experimental results are as follows: Figure 5 As shown, this indicates that the humanized anti-human CD138 antibody can effectively inhibit tumor cell proliferation.

[0181] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

[0182] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0183] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. An anti-CD138 antibody or its antigen-binding fragment, characterized in that, Including the following CDR sequences: Heavy chain variable region CDR1: DYTIH (SEQ ID NO: 1), Heavy chain variable region CDR2: WFYPGSDNIKYNEKFKD (SEQ ID NO: 2), Heavy chain variable region CDR3: HERGYSTPGDV (SEQ ID NO: 3). Light chain variable region CDR1: RSX1QSLLHSNX2NTYLH (SEQ ID NO: 4), Light chain variable region CDR2: RVSNRFS (SEQ ID NO: 5), Light chain variable region CDR3: SQSSRIPWT (SEQ ID NO: 6), Where X1 is selected from N or Q, and X2 is selected from G or A.

2. The antibody or antigen-binding fragment according to claim 1, characterized in that, include: The heavy chain variable region CDR1 sequence shown in SEQ ID NO: 1, the heavy chain variable region CDR2 shown in SEQ ID NO: 2, the heavy chain variable region CDR3 shown in SEQ ID NO: 3, the light chain variable region CDR1 shown in SEQ ID NO: 7, the light chain variable region CDR2 shown in SEQ ID NO: 5, and the light chain variable region CDR3 shown in SEQ ID NO:

6.

3. The antibody or antigen-binding fragment according to claim 1, characterized in that, include: The heavy chain variable region CDR1 sequence shown in SEQ ID NO: 1, the heavy chain variable region CDR2 shown in SEQ ID NO: 2, the heavy chain variable region CDR3 shown in SEQ ID NO: 3, the light chain variable region CDR1 shown in SEQ ID NO: 8, the light chain variable region CDR2 shown in SEQ ID NO: 5, and the light chain variable region CDR3 shown in SEQ ID NO:

6.

4. The antibody or antigen-binding fragment according to claim 1, characterized in that, include: Heavy chain FR region and light chain FR region.

5. The antibody or antigen-binding fragment according to claim 4, characterized in that, At least a portion of at least one of the heavy chain FR region and the light chain FR region is derived from at least one of primate-derived antibodies and murine antibodies or mutants thereof.

6. The antibody-antigen binding fragment according to claim 4, characterized in that, At least a portion of at least one of the heavy chain FR region and the light chain FR region is derived from a human antibody.

7. The antibody or antigen-binding fragment according to claim 4, characterized in that, Includes at least one of the following: At least one of the heavy chain frame regions HFR1, HFR2, HFR3 and HFR4 sequences as shown in SEQ ID NO: 9-12; At least one of the heavy chain frame regions HFR1, HFR2, HFR3 and HFR4 sequences as shown in SEQ ID NO: 17-20; At least one of the light chain framework regions LFR1, LFR2, LFR3 and LFR4 sequences as shown in SEQ ID NO: 13-16; and At least one of the light chain framework regions LFR1, LFR2, LFR3 and LFR4 sequences as shown in SEQ ID NO: 21-24.

8. The antibody or its antigen-binding fragment according to claim 7, characterized in that, include: At least one of the heavy chain frame region sequences HFR1, HFR2, HFR3, and HFR4 as shown in SEQ ID NO: 9-12; at least one of the light chain frame region sequences LFR1, LFR2, LFR3, and LFR4 as shown in SEQ ID NO: 13-16; or At least one of the heavy chain frame regions HFR1, HFR2, HFR3 and HFR4 sequences as shown in SEQ ID NO:17-20; and at least one of the light chain frame regions LFR1, LFR2, LFR3 and LFR4 sequences as shown in SEQ ID NO:21-24.

9. The antibody or its antigen-binding fragment according to claim 1, characterized in that, include: Heavy chain variable regions as shown in SEQ ID NO: 25 or SEQ ID NO: 27; and / or Light chain variable regions as shown in SEQ ID NO: 26, SEQ ID NO: 28 or 43.

10. The antibody or its antigen-binding fragment according to claim 1, characterized in that, include: 1) The heavy chain variable region as shown in SEQ ID NO: 25, and the light chain variable region as shown in SEQ ID NO: 26 or 43; or 2) The heavy chain variable region as shown in SEQ ID NO:27, and the light chain variable region as shown in SEQ ID NO:

28.

11. The antibody or antigen-binding fragment according to claim 1, characterized in that, The antibody or antigen-binding fragment contains at least one of a heavy chain constant region and a light chain constant region, and at least a portion of at least one of the heavy chain constant region and the light chain constant region is derived from at least one of a primate-derived antibody and a murine antibody or a mutant thereof.

12. The antibody or antigen-binding fragment according to claim 1, characterized in that, The antibody or antigen-binding fragment contains at least one of a heavy chain constant region and a light chain constant region, and at least a portion of at least one of the heavy chain constant region and the light chain constant region is derived from a human antibody.

13. The antibody or antigen-binding fragment according to claim 11, characterized in that, Both the light chain constant region and the heavy chain constant region are derived from mouse IgG antibodies or their mutants, or human IgG antibodies or their mutants.

14. The antibody or antigen-binding fragment according to claim 11, characterized in that, Both the light chain constant region and the heavy chain constant region are derived from mouse IgG1 antibody or its mutant, or human IgG1 antibody or its mutant.

15. The antibody or antigen-binding fragment according to claim 1, characterized in that, The antibody has a heavy chain constant region as shown in SEQ ID NO:29 or 31 and / or a light chain constant region as shown in SEQ ID NO:30 or 32.

16. The antibody or antigen-binding fragment according to claim 1, characterized in that, A heavy chain having the amino acid sequences shown in any one of SEQ ID NO:33 and 35, and a light chain having the amino acid sequences shown in any one of SEQ ID NO:34, 36, and 44.

17. The antibody or its antigen-binding fragment according to claim 1, characterized in that, The antibody or antigen-binding fragment is at least one of monoclonal antibody, Fv, single-chain antibody, and Fab antibody.

18. The antibody or its antigen-binding fragment according to claim 1, characterized in that, The antibody or its antigen-binding fragment can bind to the amino acid sequence shown in SEQ ID NO: 37 or 38.

19. A nucleic acid molecule, characterized in that, The nucleic acid molecule encodes the antibody or antigen-binding fragment as described in any one of claims 1-18.

20. An expression carrier, characterized in that, Carrying the nucleic acid molecule as described in claim 19.

21. A recombinant cell, characterized in that, It carries the nucleic acid molecule of claim 19, the expression vector of claim 20, or an antibody or antigen-binding fragment of any one of claims 1-18.

22. The recombinant cell according to claim 21, characterized in that, The recombinant cells are obtained by introducing the expression vector of claim 20 into host cells.

23. The recombinant cell according to claim 21, characterized in that, The recombinant cells are eukaryotic cells.

24. The recombinant cell according to claim 21, characterized in that, The recombinant cells are mammalian cells.

25. A composition, characterized in that, It includes the antibody according to any one of claims 1-18, the nucleic acid molecule according to claim 19, the expression vector according to claim 20, or the recombinant cell according to any one of claims 21-24.

26. A drug, characterized in that, It includes the antibody according to any one of claims 1-18, the nucleic acid molecule according to claim 19, the expression vector according to claim 20, the recombinant cell according to any one of claims 21-24, or the composition according to claim 25.

27. A kit for detecting CD138, characterized in that, The kit contains the antibody or its antigen-binding fragment as described in any one of claims 1-18, the nucleic acid molecule as described in claim 19, the expression vector as described in claim 20, or the recombinant cells as described in any one of claims 21-24.

28. The use of the antibody or antigen-binding fragment thereof of any one of claims 1-18, the nucleic acid molecule of claim 19, the expression vector of claim 20, the recombinant cell of any one of claims 21-24, or the composition of claim 25 in the preparation of a medicament for the prevention and / or treatment of CD138-related diseases, wherein the CD138-related diseases are cancers, and the cancers are at least one of multiple myeloma, lung cancer, gastric cancer, colorectal cancer, pancreatic cancer, breast cancer, and bladder cancer.

29. Use of the antibody or antigen-binding fragment according to any one of claims 1-18 in the preparation of a kit for detecting CD138.

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