Human antibody specifically binding to human TREM2 protein, and use thereof

Abstract

The present invention relates to a human antibody specifically binding to a human TREM2 protein, and use thereof. The human monoclonal antibody specifically binding to TREM2 has been discovered through biopanning using a human synthetic antibody phage display library, and the antigen binding ability and biological activity of the discovered antibody have been identified. The present invention has a high affinity for TREM2, and thus enables the development of an antibody-based diagnosis system capable of diagnosing TREM2 as a biomarker of various Alzheimer's dementia. In addition, since a conventional therapeutic agent for Alzheimer's disease is mostly a symptom reliever through the temporary regulation of neurotransmitters, it is considered that the development of antibodies targeting TREM2 can lead to the development of promising new drugs having substantial therapeutic effects.

Description

Human antibodies specifically binding to human TREM2 protein and uses thereof

[0001] The present invention relates to a human antibody that specifically binds to human TREM2 (Triggering receptor expressed on myeloid cells 2) protein and its use.

[0002] TREM2 (Triggering receptor expressed on myeloid cells 2) is a receptor that transmits signals through an adapter protein called DAP12. It is known to regulate myeloid cell function and suppresses inflammatory responses by inhibiting cytokine expression, confirming that TREM2 is involved in immune regulation. The TREM2 protein is mainly present in microglia and has been found to play an important role in phagocytosis of dementia target factor amyloid-beta, processing damaged nerve cells, and maintaining immune cell homeostasis.

[0003] Recently, a study reported that TREM2 mutants triple the risk of Alzheimer's disease, further highlighting its potential as a biomarker for research on brain diseases like Alzheimer's and as a potential target for novel therapeutics. However, as a membrane protein, TREM2 is difficult to purify in its native, intact form within cells while maximally preserving its intrinsic intracellular functions. Furthermore, antibodies capable of specifically detecting TREM2 remain insufficiently developed.

[0004] Phage display technology is a technology that produces a human antibody library and displays it on the surface of bacteriophage in the form of antibody fragments (Fab, ScFv) to select antibody clones against specific antigens. The possibility of screening virtually any type of human recombinant monoclonal antibody that specifically reacts with an antigen from a single-pot antibody library system has been proposed, suggesting that utilizing phage display antibody technology can yield a variety of antibody fragments (in Fab or ScFv form) that can be applied in in vivo diagnostics or therapeutics.

[0005] An object of the present invention is to provide a human antibody or an antigen-binding fragment thereof that specifically binds to human TREM2 protein.

[0006] Another object of the present invention is to provide a nucleic acid molecule encoding the human antibody or an antigen-binding fragment thereof, a recombinant expression vector comprising the nucleic acid molecule, and an isolated cell transformed with the recombinant expression vector.

[0007] Another object of the present invention is to provide a composition for detecting human TREM2 antigen comprising the human antibody or antigen-binding fragment thereof as an active ingredient.

[0008] Another object of the present invention is to provide a composition for diagnosing Alzheimer's disease comprising the human antibody or an antigen-binding fragment thereof as an active ingredient.

[0009] In order to achieve the above object, the present invention provides a heavy chain FR1 comprising an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 selected from the group consisting of an amino acid sequence represented by SEQ ID NO: 2, an amino acid sequence represented by SEQ ID NO: 8, and an amino acid sequence represented by SEQ ID NO: 13, a heavy chain FR2 comprising an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 selected from the group consisting of an amino acid sequence represented by SEQ ID NO: 4, an amino acid sequence represented by SEQ ID NO: 9, an amino acid sequence represented by SEQ ID NO: 11, an amino acid sequence represented by SEQ ID NO: 14, an amino acid sequence represented by SEQ ID NO: 16, an amino acid sequence represented by SEQ ID NO: 18, an amino acid sequence represented by SEQ ID NO: 20, and an amino acid sequence represented by SEQ ID NO: 22, a heavy chain FR3 comprising an amino acid sequence represented by SEQ ID NO: 5, a heavy chain FR1 comprising an amino acid sequence represented by SEQ ID NO: 6, an amino acid sequence represented by SEQ ID NO: 10, an amino acid sequence represented by SEQ ID NO: 12, an amino acid sequence represented by SEQ ID NO: 15, an amino acid sequence represented by SEQ ID NO: 17, a heavy chain FR3 comprising an amino acid sequence represented by SEQ ID NO: 5, an amino acid sequence represented by SEQ ID NO: 6, an amino acid sequence represented by SEQ ID NO: 10, an amino acid sequence represented by SEQ ID NO: 12, an amino acid sequence represented by SEQ ID NO: 15, an amino acid sequence represented by SEQ ID NO: 17, a heavy chain CDR2 selected from the group consisting of an amino acid sequence represented by SEQ ID NO: 14, an amino acid sequence represented by SEQ ID NO: 16, an amino acid sequence represented by SEQ ID NO: 18, an amino acid sequence represented by SEQ ID NO: 18, a A heavy chain variable region comprising a heavy chain CDR3 selected from the group consisting of an amino acid sequence represented by SEQ ID NO: 19, an amino acid sequence represented by SEQ ID NO: 21, and an amino acid sequence represented by SEQ ID NO: 23, and a heavy chain FR4 comprising an amino acid sequence represented by SEQ ID NO: 7;and a light chain FR1 comprising an amino acid sequence represented by SEQ ID NO: 24, an amino acid sequence represented by SEQ ID NO: 25, an amino acid sequence represented by SEQ ID NO: 31, an amino acid sequence represented by SEQ ID NO: 36, an amino acid sequence represented by SEQ ID NO: 38, and an amino acid sequence represented by SEQ ID NO: 42, a light chain CDR1 selected from the group consisting of a light chain FR2 comprising an amino acid sequence represented by SEQ ID NO: 26, an amino acid sequence represented by SEQ ID NO: 27, an amino acid sequence represented by SEQ ID NO: 32, and an amino acid sequence represented by SEQ ID NO: 34, a light chain FR3 comprising an amino acid sequence represented by SEQ ID NO: 28, an amino acid sequence represented by SEQ ID NO: 29, an amino acid sequence represented by SEQ ID NO: 33, an amino acid sequence represented by SEQ ID NO: 35, an amino acid sequence represented by SEQ ID NO: 37, an amino acid sequence represented by SEQ ID NO: 39, an amino acid sequence represented by SEQ ID NO: 40, and an amino acid sequence represented by SEQ ID NO: 41, and a light chain CDR2 selected from the group consisting of an amino acid sequence represented by SEQ ID NO: 29, an amino acid sequence represented by SEQ ID NO: 33, an amino acid sequence represented by SEQ ID NO: 35, an amino acid sequence represented by SEQ ID NO: 37, an amino acid sequence represented by SEQ ID NO: 39, an amino acid sequence represented by SEQ ID NO: 40, and an amino acid sequence represented by SEQ ID NO: 41, and a light chain CDR3 selected from the group consisting of an amino acid sequence represented by SEQ ID NO: 25, an amino acid sequence represented by SEQ ID NO: 31, an amino acid sequence represented by SEQ ID NO: 36, an amino acid sequence represented by SEQ ID NO: 38, and an amino acid sequence represented by SEQ ID NO: Provided is a human antibody or antigen-binding fragment thereof that specifically binds to human TREM2 protein, comprising a light chain variable region comprising a light chain FR4 consisting of an amino acid sequence represented by 30.

[0010] Additionally, the present invention provides a nucleic acid molecule encoding the human antibody or antigen-binding fragment thereof.

[0011] In addition, the present invention provides a recombinant expression vector comprising the nucleic acid molecule.

[0012] In addition, the present invention provides an isolated cell transformed with the recombinant expression vector.

[0013] In addition, the present invention provides a composition for detecting human TREM2 antigen comprising the human antibody or antigen-binding fragment thereof as an active ingredient.

[0014] In addition, the present invention provides a composition for diagnosing Alzheimer's disease comprising the human antibody or an antigen-binding fragment thereof as an active ingredient.

[0015] The present invention relates to a human antibody that specifically binds to the human TREM2 protein and its use. A human monoclonal antibody that specifically binds to TREM2 was discovered through a biopanning technique using a human synthetic antibody phage display library. The antigen-binding ability and biological activity of the discovered antibody were confirmed. The present invention has high affinity for TREM2, and thus, it is possible to develop an antibody-based diagnostic system capable of diagnosing TREM2 as a biomarker for various Alzheimer's diseases. Furthermore, since most existing Alzheimer's treatment drugs are symptom relief drugs that temporarily regulate neurotransmitters, it is believed that the development of an antibody targeting TREM2 could lead to the development of a promising new drug with a substantial therapeutic effect.

[0016] Figure 1 shows the results of screening scFvs that bind to human TREM2 protein through phage display panning.

[0017] Figure 2 shows the results of SDS-PAGE gel analysis and SE-HPLC analysis of TREM2 binding antibody protein.

[0018] Figure 3 shows the results of evaluating the binding affinity of TREM2 binding antibodies to human TREM2.

[0019] Figure 4 shows the results of the efficacy verification of human antibodies.

[0020] The present invention relates to a heavy chain FR1 comprising an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 selected from the group consisting of an amino acid sequence represented by SEQ ID NO: 2, an amino acid sequence represented by SEQ ID NO: 8, and an amino acid sequence represented by SEQ ID NO: 13, a heavy chain FR2 comprising an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 selected from the group consisting of an amino acid sequence represented by SEQ ID NO: 4, an amino acid sequence represented by SEQ ID NO: 9, an amino acid sequence represented by SEQ ID NO: 11, an amino acid sequence represented by SEQ ID NO: 14, an amino acid sequence represented by SEQ ID NO: 16, an amino acid sequence represented by SEQ ID NO: 18, an amino acid sequence represented by SEQ ID NO: 20, and an amino acid sequence represented by SEQ ID NO: 22, a heavy chain FR3 comprising an amino acid sequence represented by SEQ ID NO: 5, a heavy chain FR1 comprising an amino acid sequence represented by SEQ ID NO: 6, an amino acid sequence represented by SEQ ID NO: 10, an amino acid sequence represented by SEQ ID NO: 12, an amino acid sequence represented by SEQ ID NO: 15, an amino acid sequence represented by SEQ ID NO: 17, an amino acid sequence represented by SEQ ID NO: 19. A heavy chain variable region comprising a heavy chain CDR3 selected from the group consisting of an amino acid sequence, an amino acid sequence represented by SEQ ID NO: 21, and an amino acid sequence represented by SEQ ID NO: 23, and a heavy chain FR4 comprising an amino acid sequence represented by SEQ ID NO: 7;and a light chain FR1 comprising an amino acid sequence represented by SEQ ID NO: 24, an amino acid sequence represented by SEQ ID NO: 25, an amino acid sequence represented by SEQ ID NO: 31, an amino acid sequence represented by SEQ ID NO: 36, an amino acid sequence represented by SEQ ID NO: 38, and an amino acid sequence represented by SEQ ID NO: 42, a light chain CDR1 selected from the group consisting of a light chain FR2 comprising an amino acid sequence represented by SEQ ID NO: 26, an amino acid sequence represented by SEQ ID NO: 27, an amino acid sequence represented by SEQ ID NO: 32, and an amino acid sequence represented by SEQ ID NO: 34, a light chain FR3 comprising an amino acid sequence represented by SEQ ID NO: 28, an amino acid sequence represented by SEQ ID NO: 29, an amino acid sequence represented by SEQ ID NO: 33, an amino acid sequence represented by SEQ ID NO: 35, an amino acid sequence represented by SEQ ID NO: 37, an amino acid sequence represented by SEQ ID NO: 39, an amino acid sequence represented by SEQ ID NO: 40, and an amino acid sequence represented by SEQ ID NO: 41, and a light chain CDR2 selected from the group consisting of an amino acid sequence represented by SEQ ID NO: 29, an amino acid sequence represented by SEQ ID NO: 33, an amino acid sequence represented by SEQ ID NO: 35, an amino acid sequence represented by SEQ ID NO: 37, an amino acid sequence represented by SEQ ID NO: 39, an amino acid sequence represented by SEQ ID NO: 40, and an amino acid sequence represented by SEQ ID NO: 41, and a light chain CDR3 selected from the group consisting of an amino acid sequence represented by SEQ ID NO: 25, an amino acid sequence represented by SEQ ID NO: 31, an amino acid sequence represented by SEQ ID NO: 36, an amino acid sequence represented by SEQ ID NO: 38, and an amino acid sequence represented by SEQ ID NO: Provided is a human antibody or antigen-binding fragment thereof that specifically binds to human TREM2 protein, comprising a light chain variable region comprising a light chain FR4 consisting of an amino acid sequence represented by 30.

[0021] Preferably, the human antibody or antigen-binding fragment thereof that specifically binds to the human TREM2 protein comprises: 1) a heavy chain variable region comprising a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 2, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 4, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 6, and a heavy chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 7; and a light chain variable region comprising a light chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 24, a light chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 25, a light chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 26, a light chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 27, a light chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 28, a light chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 29, and a light chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 30, or

[0022] 2) A heavy chain variable region comprising a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 8, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 9, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 10, and a heavy chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 7; and a light chain variable region comprising a light chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 24, a light chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 31, a light chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 26, a light chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 32, a light chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 28, a light chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 33, and a light chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 30, or

[0023] 3) A heavy chain variable region comprising a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 8, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 11, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 12, and a heavy chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 7; and a light chain variable region comprising a light chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 24, a light chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 25, a light chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 26, a light chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 34, a light chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 28, a light chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 35, and a light chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 30, or

[0024] 4) A heavy chain variable region comprising a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 13, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 14, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 15, and a heavy chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 7; and a light chain variable region comprising a light chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 24, a light chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 36, a light chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 26, a light chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 34, a light chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 28, a light chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 37, and a light chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 30, or

[0025] 5) A heavy chain variable region comprising a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 2, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 16, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 17, and a heavy chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 7; and a light chain variable region comprising a light chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 24, a light chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 38, a light chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 26, a light chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 32, a light chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 28, a light chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 39, and a light chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 30, or

[0026] 6) A heavy chain variable region comprising a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 2, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 18, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 19, and a heavy chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 7; and a light chain variable region comprising a light chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 24, a light chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 25, a light chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 26, a light chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 34, a light chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 28, a light chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 40, and a light chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 30, or

[0027] 7) A heavy chain variable region comprising a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 8, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 20, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 21, and a heavy chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 7; and a light chain variable region comprising a light chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 24, a light chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 25, a light chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 26, a light chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 32, a light chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 28, a light chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 41, and a light chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 30, or

[0028] 8) A heavy chain variable region comprising a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 8, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 22, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 23, and a heavy chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 7; And a human antibody or antigen-binding fragment thereof, characterized in that it comprises a light chain variable region comprising a light chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 24, a light chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 42, a light chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 26, a light chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 32, a light chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 28, a light chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 35, and a light chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 30, but is not limited thereto.

[0029]

[0030] The term "antibody" as used herein refers to a protein molecule that acts as a receptor that specifically recognizes an antigen, including an immunoglobulin molecule that immunologically reacts with a specific antigen, and examples thereof may include monoclonal antibodies, polyclonal antibodies, full-length antibodies, and antibody fragments. In addition, the term "antibody" may include bivalent or dual-specific molecules (e.g., bispecific antibodies), diabodies, triabodies, or tetrabodies.

[0031]

[0032] As used herein, the term “monoclonal antibody” refers to an antibody molecule of a single molecular composition obtained from a substantially identical antibody population, and such monoclonal antibodies exhibit single binding affinity and binding affinity for a specific epitope, unlike polyclonal antibodies that can bind to multiple epitopes. As used herein, the term “full-length antibody” refers to a structure having two full-length light chains and two full-length heavy chains, each light chain being linked to a heavy chain by a disulfide bond. The heavy chain constant region has gamma (γ), mu (μ), alpha (α), delta (δ), and epsilon (ε) types and has subclasses of gamma1 (γ1), gamma2 (γ2), gamma3 (γ3), gamma4 (γ4), alpha1 (α1), and alpha2 (α2). The constant region of the light chain has kappa (κ) and lambda (λ) types. IgG has subtypes, including IgG1, IgG2, IgG3, and IgG4.

[0033]

[0034] As used herein, the term "human antibody" refers to a molecule derived from human immunoglobulin, wherein the entire amino acid sequence constituting the antibody, including the complementarity-determining region and the structural region, is comprised of the amino acid sequence of human immunoglobulin. Human antibodies are commonly used to treat human diseases and may have at least three potential advantages. First, they interact better with the human immune system, allowing for more efficient destruction of target cells, for example, through complement-dependent cytotoxicity (CDC) or antibody-dependent cell-mediated cytotoxicity (ADCC). Second, there is the advantage that the human immune system does not recognize the antibody as foreign. Third, there is the advantage that the half-life in the human circulation is similar to that of naturally occurring antibodies, even when administered in smaller doses and less frequently.

[0035]

[0036] In the present invention, the term “heavy chain” may include both a full-length heavy chain and fragments thereof, which include a variable region VH comprising an amino acid sequence having sufficient variable region sequence to confer specificity to an antigen, and three constant regions CH1, CH2, and CH3. In addition, the term “light chain” in the present invention may include both a full-length light chain and fragments thereof, which include a variable region VL comprising an amino acid sequence having sufficient variable region sequence to confer specificity to an antigen, and a constant region CL.

[0037]

[0038] In the present invention, the terms “fragment,” “antibody fragment,” and “antigen-binding fragment” are used interchangeably to refer to any fragment of an antibody of the present invention that retains the antigen-binding function of the antibody. Exemplary antigen-binding fragments include, but are not limited to, Fab, Fab', F(ab')2, and Fv.

[0039] The antibodies or antigen-binding fragments thereof of the present invention may include not only the sequences of the antibodies described herein, but also biological equivalents thereof, to the extent that they can exhibit the ability to specifically bind to human TREM2. For example, additional changes may be made to the amino acid sequence of the antibody to further improve the binding affinity and / or other biological properties of the antibody. Such modifications include, for example, deletions, insertions, and / or substitutions of amino acid sequence residues of the antibody. Such amino acid mutations are made based on the relative similarity of the amino acid side chain substituents, such as hydrophobicity, hydrophilicity, charge, size, etc. Analysis of the size, shape, and type of amino acid side chain substituents reveals that arginine, lysine, and histidine are all positively charged residues; alanine, glycine, and serine have similar sizes; and phenylalanine, tryptophan, and tyrosine have similar shapes. Therefore, based on this, arginine, lysine, and histidine; alanine, glycine, and serine; And phenylalanine, tryptophan, and tyrosine are biologically functional equivalents.

[0040]

[0041] Additionally, the present invention provides a nucleic acid molecule encoding the human antibody or antigen-binding fragment thereof.

[0042] As used herein, the term “nucleic acid molecule” has a comprehensive meaning including DNA (gDNA and cDNA) and RNA molecules, and nucleotides, which are the basic structural units of nucleic acid molecules, include not only natural nucleotides but also analogues in which sugar or base moieties are modified. The sequence of the nucleic acid molecule encoding the heavy and light chain variable regions of the present invention may be modified, and such modifications include additions, deletions, or non-conservative or conservative substitutions of nucleotides.

[0043]

[0044] In addition, the present invention provides a recombinant expression vector comprising the nucleic acid molecule.

[0045] In the present invention, "vector" means a self-replicating DNA molecule used to carry a clone gene (or other piece of clone DNA).

[0046] In the present invention, an “expression vector” refers to a recombinant DNA molecule containing a desired coding sequence and an appropriate nucleic acid sequence essential for expressing the coding sequence operably linked to the vector in a specific host organism. The expression vector may preferably include one or more selectable markers. The markers are typically nucleic acid sequences having properties that can be selected by chemical methods, and include all genes that can distinguish transformed cells from non-transformed cells. Examples include, but are not limited to, antibiotic resistance genes such as ampicillin, kanamycin, geneticin (G418), bleomycin, hygromycin, and chloramphenicol, and can be appropriately selected by those skilled in the art.

[0047] Any of a wide variety of expression control sequences may be used in the vector to express the DNA sequence of the present invention. Examples of useful expression control sequences include, for example, the early and late promoters of SV40 or adenovirus, the promoter and enhancer of CMV, the LTR of retroviruses, the lac system, the trp system, the TAC or TRC system, the T3 and T7 promoters, the major operator and promoter region of phage lambda, the regulatory region of the fd-encoded protein, the promoter for 3-phosphoglycerate kinase or other glycolytic enzymes, the promoters of such phosphatases, e.g., Pho5, the promoter of the yeast alpha-mating system, and any other sequence known to regulate the expression of genes of prokaryotes or eukaryotes or their viruses, and various combinations thereof.

[0048] The vector expressing the antibody of the present invention can be either a vector system in which the light chain and the heavy chain are simultaneously expressed from a single vector, or a system in which the light chain and the heavy chain are each expressed from separate vectors. In the latter case, the two vectors are introduced into a host cell through co-transformation and targeted transformation. Co-transformation is a method in which vector DNA encoding the light chain and the heavy chain are simultaneously introduced into a host cell, and then cells expressing both the light chain and the heavy chain are selected. Targeted transformation is a method in which cells transformed with a vector containing a light chain (or heavy chain) are selected, and the selected cells expressing the light chain are transformed again with a vector containing a heavy chain (or light chain), thereby finally selecting cells expressing both the light chain and the heavy chain.

[0049]

[0050] In addition, the present invention provides an isolated cell transformed with a recombinant expression vector.

[0051] The cell capable of stably and continuously cloning and expressing the vector of the present invention may be any host cell known in the art, including, but not limited to, prokaryotic host cells such as strains of the genus Bacillus such as Escherichia coli, Bacillus subtilis and Bacillus thuringiensis, Streptomyces, Pseudomonas (e.g., Pseudomonas putida), Proteus mirabilis or Staphylococcus (e.g., Staphylococcus carnosus).

[0052] In the method for producing the above antibody or antigen-binding fragment thereof, the culture of transformed cells can be performed according to appropriate media and culture conditions known in the relevant technical field. Such culture process can be easily adjusted and used by those skilled in the art depending on the selected strain. Cell culture is classified into suspension culture and attachment culture depending on the cell growth method, and batch, fed-batch, and continuous culture methods depending on the culture method. The culture medium used must appropriately satisfy the requirements of the specific strain.

[0053]

[0054] In addition, the present invention provides a composition for detecting human TREM2 antigen comprising the human antibody or antigen-binding fragment thereof as an active ingredient.

[0055]

[0056] In addition, the present invention provides a composition for diagnosing Alzheimer's disease comprising the human antibody or an antigen-binding fragment thereof as an active ingredient.

[0057] Hereinafter, to aid understanding of the present invention, examples will be given in detail. However, the following examples are intended only to illustrate the scope of the present invention and are not intended to limit its scope. These examples are provided to more fully explain the present invention to those of average skill in the art.

[0058]

[0059] <Example 1> Preparation of TREM2-binding antibody

[0060] 1. Selection of scFv binding to human TREM2 protein through phage display panning

[0061] Panning against human TREM2 protein was performed using synthetic human antibody phage display libraries (KFab-I, KFab-II, KscFv-I). ~1.0 × 10^12 cfu / ml of the phage library was added to an immunotube immobilized with human TREM2 protein (10 μg / ml), and the mixture was allowed to bind at 37°C. After the reaction was completed, unbound phages were removed by washing three times with 0.05% tween-20-containing phosphate-buffered saline (PBST). 1 mL of 100 mM trimethylamine was added to the immunotube for 10 minutes to harvest (elution) phages bound to human TREM2 protein. The harvested phage was neutralized by adding Tris-Glycine buffer (pH 7.5), and then E. coli TG1 cultured at mid-log phase (OD600 = 0.5-1.0) was added to induce infection. Some were used for output titration, and the remaining cell pellets were collected after culture and inoculated onto 2-YT medium plates. The cultured colonies were collected the next day to prepare phage for the next round of panning. As the subsequent panning rounds progressed, the coating concentration of human TREM2 protein was lowered and the number of washes with PBS-T was increased to amplify and concentrate the antigen-specific phage. A PBS control panning without immobilized human TREM2 protein was also performed in parallel, and the output titers of each round were compared, and the results are shown in Figure 1 through the elution titer ratio (the output titer divided by the output titer of the control). In rounds 3 and 4, the phage titer (the number of infectious particles contained in the phage solution) increased by at least 1,000-fold and up to 15,000-fold compared to the control group.

[0062]

[0063] 2. Selection of monoclonal phage antibodies that specifically bind to human TREM2 protein

[0064] In order to select a monoclonal antibody that specifically binds to human TREM2 protein from the phages obtained through the above panning, a monoclonal phage ELISA and a soluble ELISA using the periplasmic fraction containing Fab and scFv through osmotic shock were performed on the clones obtained in the 3rd or 4th round of panning. The completed panning round clones were used to prepare for phage-antibody elution. The phage ELISA was performed on a 96-well ELISA plate coated with 2 μg / ml of human TREM2 protein, and after reacting with Anti-M13-HRP (1:5,000) antibody, the color was developed by treating with TMB (3,3', 5,5'-Tetramethylbenzidine) substrate, and the reaction was stopped by treating with 2N H2SO4. For human TREM2 protein, the absorbance (A450 nm) cut-off was set to 0.4 or higher, and for the negative control, PBS control, the clones with an absorbance (A450 nm) cut-off of 0.15 or lower were selected as clones that specifically bind.

[0065] To select clones with high affinity for human TREM2 protein, the periplasmic fraction containing Fab and scFv was secured through osmotic shock using TES solution (20% w / v sucrose, 50 mM Tris, 1 mM EDTA, pH 8.0). The soluble ELISA was performed on a 96-well ELISA plate coated with 2 μg / ml of human TREM2 protein, and the antibody was reacted with anti-VK-HRP (1:10,000), followed by color development with TMB substrate, and the reaction was stopped by treatment with 2N H2SO4. Clones were considered to bind specifically when the absorbance (A450 nm) of the phage-antibody was more than twice that of the periplasmic fraction containing Fab and scFv for human TREM2 protein (A450 nm), and the corresponding clones were finally selected.

[0066]

[0067] The CDR and framework amino acid sequences of the finally selected antibodies are listed in Table 1 below.

[0068]

[0069]

[0070] IDFHR1CDR-H1FHR2CDR-H2FHR3CDR-H3FHR4A9EVQLVESGGGLVQPGGSLRLSCAASGFTFS(SEQ ID NO: 1)NYAMH(SEQ ID NO: 2)WVRQAPGKGLEWVS(SEQ ID NO: 3)AISGSGGNTYYADSVKG(SEQ ID NO: 4)RFTISRDNSKNTLYLQMNSLRAEDTAVYYCAK(SEQ ID NO: 5)HERTWGSQYMDH(SEQ ID NO: 6)WGQGTLVTVSS(SEQ ID NO: 7)GAAGTACAGTTGGTCGAAAGTGGCGGTGGCCTCGTGCAACCGGGTGGTTCACTGCGTCTGAGCTGCGCCGCCTCGGGTTTTACTTTCTCT(SEQ ID NO: 43)AATTATGCAATGCAC(SEQ ID NO: 44)TGGGTTCGTCAGGCGCCGGGCAAGGGTCTCGAATGGGTTTCA(SEQ ID NO: 45)GCAATCTCTGGTTCTGGTGGTAATACTTACTATGCCGATTCAGTGAAGGGT(SEQ ID NO: 46)CGCTTTACCATTTCCCGTGACAACTCTAAGAATACTCTGTATCTGCAGATGAACTCGCTGCGTGCCGAAGACACGGCCGTCTATTATTGCGCCAAA(SEQ ID NO: 47)CATGAACGTACTTGGGGTTCTCAGTACATGGATCAT(SEQ ID NO: 48)TGGGGTCAGGGCACTTTAGTGACCGTCTCATCGGGTGGAGGCGGTTCAGGCGGAGGTGGATCCGGCGGTGGCGGATCG(SEQ ID NO: 49)B1EVQLVESGGGLVQPGGSLRLSCAASGFTFS(SEQ ID NO: 1)SYAMH(SEQ ID NO: 8) WVRQAPGKGLEWVS (SEQ ID NO: 3) SIKSSGSYTYYADSVKG (SEQ ID NO: 9) RFTISRDNSKNTLYLQMNSLRAEDTAVYYCAK (SEQ ID NO: 5) HYYTSMDH (SEQ ID NO: 10) WGQGTLVTVSS (SEQ ID NO: 7) GAATGCAAGTTGGTCGAAAGTGGCGGTGGCCTCGTGCAACCGGGTGGTTCACTGCGTCTGAGCTGCGCCGCCTCGGGTTTTACTTTCTCT (SEQ ID NO: 43) TCTTATGCAATGCAC (SEQ ID NO:50)TGGGTTCGTCAGGCGCCGGGCAAGGGTCTCGAATGGGTTTCA(SEQ ID NO: 45)TCTATCAAATCTTCTGGTTCTTACACTTACTATGCCGATTCAGTGAAGGGT(SEQ ID NO: 51)CGCTTTACCATTTCCCGTGACAACTCTAAGAATACTCTGTATCTGCAGATGAACTCGCTGCGTGCCGAAGACACGGCCGTCTATTATTGCGCCAAA(SEQ ID NO: 47)CATTACTACACTTCTATGGATCAT(SEQ ID NO: 52)TGGGGTCAGGGCACTTTAGTGACCGTCTCATCG(SEQ ID NO: 49)B2EVQLVESGGGLVQPGGSLRLSCAASGFTFS(SEQ ID NO: 1)SYAMH(SEQ ID NO: 8)WVRQAPGKGLEWVS(SEQ ID NO: 3)AISSDGGNKYYADSVKG(SEQ ID NO: 11)RFTISRDNSKNTLYLQMNSLRAEDTAVYYCAK(SEQ ID NO: 5)HEYSSGWQYMDV(SEQ ID NO: 12)WGQGTLVTVSS(SEQ ID NO: 7)GAAGTACAGTTGGTCGAAAGTGGCGGTGGCCTCGCGCAACCGGGTGGTTCACTGCGTCTGAGCTGCGCCGCCTCGGGTTTTACTTTCTCT(SEQ ID NO: 43)TCTTATGCAATGCAC(SEQ ID NO: 50)TGGGTTCGTCAGGCGCCGGGCAAGGGTCTCGAATGGGTTTCA(SEQ ID NO: 45)GCAATCTCTTCTGATGGTGGTAATAAATACTATGCCGATTCAGTGAAGGGT(SEQ ID NO: 53)CGCTTTACCATTTCCCGTGACAACTCTAAGAATACTCTGTATCTGCAGATGAACTCGCTGCGTGCCGAAGACACGGCCGTCTATTATTGCGCCAAA(SEQ ID NO: 47)CATGAATACTCTTCTGGTTGGCAGTACATGGATGTT(SEQ ID NO: 54)TGGGGTCAGGGCACTTTAGTGACCGTCTCATCGGGTGGAGGCGGTTCAGGCGGAGGTGGATCCGGCGGTGGCGGATCG(SEQ ID NO: 49)B7EVQLVESGGGLVQPGGSLRLSCAASGFTFS(SEQ ID NO: 1)DYAMH(SEQ ID NO:13) WVRQAPGKGLEWVS (SEQ ID NO: 3) SISSTGSSTYYADSVKG (SEQ ID NO: 14) RFTISRDNSKNTLYLQMNSLRAEDTAVYYCAK (SEQ ID NO: 5) HYYTAMDV (SEQ ID NO: 15) WGQGTLVTVSS (SEQ ID NO: 7) GAAGATACAGTTGGTCGAAAGTGGCGGTGGCCTCGTGCAACCGGGTGGTTCACTGCGTCTGAGCTGCGCCGCCTCGGGTTTTACTTTCTCT (SEQ ID NO: 43) GAATGCAATGCAC (SEQ ID NO: 55) TGGGTTCGTCAGGCGCCGGGCAAGGGTCTCGAATGGGTTTCA (SEQ ID NO: 45) TCTATCTCTTCTACTGGTTCTTCTACTTACTATGCCGATTCAGTGAAGGGT (SEQ ID NO: 56)CGCTTTACCATTTCCCGTGACAACTCTAAGAATACTCTGTATCTGCAGATGAACTCGCTGCGTGCCGAAGACACGGCCGTCTATTATTGCGCCAAA(SEQ ID NO: 47)CATTACTACACTGCAATGGATGTT(SEQ ID NO: 57)TGGGGTCAGGGCACTTTAGTGACCGTCTCATCG(SEQ ID NO: 49)E10EVQLVESGGGLVQPGGSLRLSCAASGFTFS(SEQ ID NO: 1)NYAMH(SEQ ID NO: 2)WVRQAPGKGLEWVS(SEQ ID NO: 3)GISGSGGTTGYADSVKG(SEQ ID NO: 16)RFTISRDNSKNTLYLQMNSLRAEDTAVYYCAK(SEQ ID NO: 5)VRGRYSSQYFDI(SEQ ID NO: 17)WGQGTLVTVSS(SEQ ID NO: 7)GAAGTACAGTTGGTCGAAAGTGGCGGTGGCCTCGTGCAACCGGGTGGTTCACTGCGTCTGAGCTGCGCCGCCTCGGGTTTTACTTTCTCT(SEQ ID NO: 43)AATTATGCAATGCAC(SEQ ID NO: 44)TGGGTTCGTCAGGCGCCGGGCAAGGGTCTCGAATGGGTTTCA(SEQ ID NO: 45)GGTATCTCTGGTTCTGGTGGTACTACTGGTTATGCCGATTCAGTGAAGGGT(SEQ ID NO:58)CGCTTTACCATTTCCCGTGACAACTCTAAGAATACTCTGTATCTGCAGATGAACTCGCTGCGTGCCGAAGACACGGCCGTCTATTATTGCGCCAAA(SEQ ID NO: 47)GTTCGTGGTCGTTACTCTTCTCAGTACTTCGATATC(SEQ ID NO: 59)TGGGGTCAGGGCACTTTAGTGACCGTCTCATCGGGTGGAGGCGGTTCAGGCGGAGGTGGATCCGGCGGTGGCGGATCG(SEQ ID NO: 49)F3EVQLVESGGGLVQPGGSLRLSCAASGFTFS(SEQ ID NO: 1)NYAMH(SEQ ID NO: 2)WVRQAPGKGLEWVS(SEQ ID NO: 3)AISGDGGNTYYADSVKG(SEQ ID NO: 18)RFTISRNNSKNTLYLQMNSLRAEDTAVYYCAK(SEQ ID NO: 5) HHVGQGVQVFDI (SEQ ID NO: 19) WGQGTLVTVSS (SEQ ID NO: 7) GAATGACAGTTGGTCGAAAGTGGCGGTGGCCTCGTGCAACCGGGTGGTTCACTGCGTCTGAGCTGCGCCGCCTCGGGTTTTACTTTCTCT (SEQ ID NO: 43) AATTATGCAATGCAC (SEQ ID NO: 44) TGGGTTCGTCAGGCGCCGGGCAAGGGTCTCGAATGGGTTTCA (SEQ ID NO: 45) GCAATCTCTGGTGATGGTGGTAATACTTACTATGCCGATTCAGTGAAGGGT (SEQ ID NO: 60) CGCTTTACCATTTCCCGTGACAACTCTAAGAATACTCTGTATCTGCAGATGAACTCGCTGCGTGCCGAAGACACGGCCGTCTATTATTGCGCCAAA (SEQ ID NO: 47)CATCATGTTGGTCAGGGTGTTCAGGTTTTCGATATC(SEQ ID NO: 61)TGGGGTCAGGGCACTTTAGTGACCGTCTCATCGGGGTGGAGGCGGTTCAGGCGGAGGTGGATCCGGCGGTGGCGGATCG(SEQ ID NO: 49)G11EVQLVESGGGLVQPGGSLRLSCAASGFTFS(SEQ ID NO: 1)SYAMH(SEQ ID NO: 8)WVRQAPGKGLEWVS(SEQ ID NO: 3)SISQSGSTKYYADSVKG(SEQ ID NO:20)RFTISRDNSKNTLYLQMNSLRAEDTAVYYCAK(SEQ ID NO: 5)HFYTAADY(SEQ ID NO: 21)WGQGTLVTVSS(SEQ ID NO: 7)GAAGTACAGTTGGTCGAAAGTGGCGGTGGCCTCGTGCAACCGGGTGGTTCACTGCGTCTGAGCTGCGCCGCCTCGGGTTTTACTTTCTCT(SEQ ID NO: 43)TCTTATGCAATGCAC(SEQ ID NO: 50)TGGGTTCGTCAGGCGCCGGGCAAGGGTCTCGAATGGGTTTCA(SEQ ID NO: 45)TCTATCTCTCAGTCTGGTTCTACTAAATACTATGCCGATTCAGTGAAGGGT(SEQ ID NO: 62)CGCTTTACCATTTCCCGTGACAACTCTAAGAATACTCTGTATCTGCAGATGAACTCGCTGCGTGCCGAAGACACGGCCGTCTATTATTGCGCCAAA(SEQ ID NO: 47)CATTTCTACACTGCAGCAGATTAC(SEQ ID NO: 63)TGGGGTCAGGGTACTCTGGTTACTGTATCATCG(SEQ ID NO: 49)H4EVQLVESGGGLVQPGGSLRLSCAASGFTFS(SEQ ID NO: 1)SYAMH(SEQ ID NO: 8)WVRQAPGKGLEWVS(SEQ ID NO: 3)SISSSGGTTYYADSVKG(SEQ ID NO: 22)RFTISRDNSKNTLYLQMNSLRAEDTAVYYCAK(SEQ ID NO: 5)HYRTAMDY(SEQ ID NO: 23)WGQGTLVTVSS(SEQ ID NO: 7)GAAGTACAGTTGGTCGAAAGTGGCGGTGGCCTCGTGCAACCGGGTGGTTCACTGCGTCTGAGCTGCGCCGCCTCGGGTTTTACTTTCTCT(SEQ ID NO: 43)TCTTATGCAATGCAC(SEQ ID NO: 50)TGGGTTCGTCAGGCGCCGGGCAAGGGTCTCGAATGGGTTTCA(SEQ ID NO: 45)TCTATCTCTTCTTCTGGTGGTACTACTTACTATGCCGATTCAGTGAAGGGT(SEQ ID NO:64)CGCTTTACCATTTCCCGTGACAACTCTAAGAATACTCTGTATCTGCAGATGAACTCGCTGCGTGCCGAAGACACGGCCGTCTATTATTGCGCCAAA(SEQ ID NO: 47)CATTACCGTACTGCAATGGATTAC(SEQ ID NO: 65)TGGGGTCAGGGCACTTTAGTGACCGTCTCATCG(SEQ ID NO: 49)IDFLR1CDR-L1FLR2CDR-L2FLR3CDR-L3FLR4A9DIQMTQSPSSLSASVGDRVTITC(SEQ ID NO: 24)RASQSISNYLN(SEQ ID NO: 25)WYQQKPGKAPKLLIY(SEQ ID NO: 26)ATSSLQS(SEQ ID NO: 27)GVPSRFSGSGSGTDFTLTISSLQPEDFATYYC(SEQ ID NO: 28)QQAYSSPWT(SEQ ID NO: 29)FGQGTKVEIK(SEQ ID NO: 30)GACATTCAAATGACGCAGAGTCCCTCCTCACTGAGTGCTAGCGTGGGCGATCGTGTGACAATTACTTGT(SEQ ID NO: 66)CGCGCTAGCCAGTCTATCTCTAATTACCTGAAC(SEQ ID NO: 67)TGGTATCAGCAGAAACCGGGCAAGGCGCCAAAATTGCTGATTTAC(SEQ ID NO: 68)GCAACTTCCTCTCTGCAGTCT(SEQ ID NO: 69)GGTGTACCGTCCCGTTTCTCTGGCAGCGGTTCTGGTACGGATTTTACCCTGACCATCTCAAGCCTCCAGCCTGAAGATTTTGCCACCTATTATTGT(SEQ ID NO: 70)CAGCAAGCATACTCTTCTCCGTGGACG(SEQ ID NO: 71)TTCGGGCAGGGAACTAAAGTGGAAATTAAA(SEQ ID NO: 72)B1DIQMTQSPSSLSASVGDRVTITC(SEQ ID NO: 24)RASQSISNWLN(SEQ ID NO: 31)WYQQKPGKAPKLLIY(SEQ ID NO: 26)AASRLQS(SEQ ID NO: 32)GVPSRFSGSGSGTDFTLTISSLQPEDFATYYC(SEQ ID NO: 28)QQSYSLPWT(SEQ ID NO: 33)FGQGTKVEIK(SEQ ID NO:30) GACATTCAAATGACGCAGAGTCCCTCCTCACTGAGTGCTAGCGTGGGCGATCGTGTGACAATTACTTGT (SEQ ID NO: 66) CGCGCTAGCCAGTCTATCTCTAATTGGCTGAAC (SEQ ID NO: 73) TGGTATCAGCAGAAACCGGGCAAGGCGCCAAAATTGCTGATTTAC (SEQ ID NO: 68) GCAGCATCCCGTCTGCAGTCT (SEQ ID NO: 74) GGTGTACCGTCCCGTTTCTCTGGCAGCGGTTCTGGTACGGATTTTACCCTGACCATCTCAAGCCTCCAGCCTGAAGATTTTGCCACCTATTATTGT (SEQ ID NO: 70) CAGCAATCTTACTCTCTGCCGTGGACG (SEQ ID NO: 75) TTCGGGCAGGGAACTAAAGTGGAAATTAAA (SEQ ID NO: 72) B2DIQMTQSPSSLSASVGDRVTITC (SEQ ID NO: 24)RASQSISNYLN(SEQ ID NO: 25)WYQQKPGKAPKLLIY(SEQ ID NO: 26)AASNLQS(SEQ ID NO: 34)GVPSRFSGSGSGTDFTLTISSLQPEDFATYYC(SEQ ID NO: 28)QQSYSSPWT(SEQ ID NO: 35)FGQGTKVEIK(SEQ ID NO: 30)GACATTCAAATGACGCAGAGTCCCTCCTCACTGAGTGCTAGCGTGGGCGATCGTGTGACAATTACTTGT(SEQ ID NO: 66)CGCGCTAGCCAGTCTATCTCTAATTACCTGAAC(SEQ ID NO: 67)TGGTATCAGCAGAAACCGGGCAAGGCGCCAAAATTGCTGATTTAC(SEQ ID NO: 68)GCAGCATCCAATCTGCAGTCT(SEQ ID NO: 76)GGTGTACCGTCCCGTTTCTCTGGCAGCGGTTCTGGTACGGATTTTACCCTGACCATCTCAAGCCTCCAGCCTGAAGATTTTGCCACCTATTATTGT(SEQ ID NO: 70)CAGCAATCTTACTCTTCTCCGTGGACG(SEQ ID NO: 77)TTCGGGCAGGGAACTAAAGTGGAAATTAAA(SEQ ID NO: 72)B7DIQMTQSPSSLSASVGDRVTITC(SEQ ID NO: 24)RASQSISSYLN(SEQ ID NO:36) WYQQKPGKAPKLLIY (SEQ ID NO: 26) AASNLQS (SEQ ID NO: 34) GVPSRFSGSGSGTDFTLTISSLQPEDFATYYC (SEQ ID NO: 28) QQSYSTPLT (SEQ ID NO: 37) FGQGTKVEIK (SEQ ID NO: 30) GACATTCAAATGACGCAGAGTCCCTCCTCACTGAGTGCTAGCGTGGGCGATCGTGTGACAATTACTTGT (SEQ ID NO: 66) CGCGCTAGCCAGTCTATCTCTTCTTACCTGAAC (SEQ ID NO: 78) TGGTATCAGCAGAAACCGGGCAAGGCGCCAAAATTGCTGATTTAC (SEQ ID NO: 68) GCAGCATCCAATCTGCAGTCT (SEQ ID NO: 76)GGTGTACCGTCCCGTTTCTCTGGCAGCGGTTCTGGTACGGATTTTACCCTGACCATCTCAAGCCTCCAGCCTGAAGATTTTGCCACCTATTATTGT(SEQ ID NO: 70)CAGCAATCTTACTCTACTCCGCTGACG(SEQ ID NO: 79)TTCGGGCAGGGAACTAAAGTGGAAATTAAA(SEQ ID NO: 72)E10DIQMTQSPSSLSASVGDRVTITC(SEQ ID NO: 24)RASQDIGRYLN(SEQ ID NO: 38)WYQQKPGKAPKLLIY(SEQ ID NO: 26)AASRLQS(SEQ ID NO: 32)GVPSRFSGSGSGTDFTLTISSLQPEDFATYYC(SEQ ID NO: 28)QQSYTSPLT(SEQ ID NO: 39)FGQGTKVEIK(SEQ ID NO: 30) GACATTCAAATGACGCAGAGTCCCTCCTCACTGAGTGCTAGCGTGGGCGATCGTGTGACAATTACTTGT (SEQ ID NO: 66) CCGCGCTAGCCAGGATATCGGTCGTTACCTGAAC (SEQ ID NO: 80) TGGTATCAGCAGAAACCGGGCAAGGCGCCAAAATTGCTGATTTAC (SEQ ID NO: 68) GCAGCATCCCGTCTGCAGTCT (SEQ ID NO: 74) GGTGTACCGTCCCGTTTCTCTGGCAGCGGTTCTGGTACGGATTTTACCCTGACCATCTCAAGCCTCCAGCCTGAAGATTTTGCCACCTATTATTGT (SEQ ID NO:70)CAGCAATCTTACACTTCTCCGCTGACG(SEQ ID NO: 81)TTCGGGCAGGGAACTAAAGTGGAAATTAAA(SEQ ID NO: 72)F3DIQMTQSPSSLSASVGDRVTITC(SEQ ID NO: 24)RASQSISNYLN(SEQ ID NO: 25)WYQQKPGKAPKLLIY(SEQ ID NO: 26)AASNLQS(SEQ ID NO: 34)GVPSRFSGSGSGTDFTLTISSLQPEDFATYYC(SEQ ID NO: 28)QQSYSFPFT(SEQ ID NO: 40)FGQGTKVEIK(SEQ ID NO: 30)GACATTCAAATGACGCAGAGTCCCTCCTCACTGAGTGCTAGCGTGGGCGATCGTGTGACAATTACTTGT(SEQ ID NO: 66)CGCGCTAGCCAGTCTATCTCTAATTACCTGAAC(SEQ ID NO: 67)TGGTATCAGCAGAAACCGGGCAAGGCGCCAAAATTGCTGATTTAC(SEQ ID NO: 68)GCAGCATCCAATCTGCAGTCT(SEQ ID NO: 76)GGTGTACCGTCCCGTTTCTCTGGCAGCGGTTCTGGTACGGATTTTACCCTGACCATCTCAAGCCTCCAGCCTGAAGATTTTGCCACCTATTATTGT(SEQ ID NO: 70)CAGCAATCTTACTCTTTTCCGTTTACG(SEQ ID NO: 82)TTCGGGCAGGGAACTAAAGTGGAAATTAAA(SEQ ID NO: 72)G11DIQMTQSPSSLSASVGDRVTITC(SEQ ID NO: 24)RASQSISNYLN(SEQ ID NO: 25)WYQQKPGKAPKLLIY(SEQ ID NO: 26)AASRLQS(SEQ ID NO: 32)GVPSRFSGSGSGTDFTLTISSLQPEDFATYYC(SEQ ID NO: 28)QQSYSTPWT(SEQ ID NO: 41)FGQGTKVEIK(SEQ ID NO: 30)GACATTCAAATGACGCAGAGTCCCTCCTCACTGAGTGCTAGCGTGGGCGATCGTGTGACAATTACTTGT(SEQ ID NO: 66)CGCGCTAGCCAGTCTATCTCTAATTACCTGAAC(SEQ ID NO: 67)TGGTATCAGCAGAAACCGGGCAAGGCGCCAAAATTGCTGATTTAC(SEQ ID NO:68)GCAGCATCCCGTCTGCAGTCT(SEQ ID NO: 74)GGTGTACCGTCCCGTTTCTCTGGCAGCGGTTCTGGTACGGATTTTACCCTGACCATCTCAAGCCTCCAGCCTGAAGATTTTGCCACCTATTATTGT(SEQ ID NO: 70)CAGCAATCTTACTCTACTCCGTGGACG(SEQ ID NO: 83)TTCGGGCAGGGAACTAAAGTGGAAATTAAA(SEQ ID NO: 72)H4DIQMTQSPSSLSASVGDRVTITC(SEQ ID NO: 24)RASQSIRNYLN(SEQ ID NO: 42)WYQQKPGKAPKLLIY(SEQ ID NO: 26)AASRLQS(SEQ ID NO: 32)GVPSRFSGSGSGTDFTLTISSLQPEDFATYYC(SEQ ID NO: 28)QQSYSSPWT(SEQ ID NO: 35)FGQGTKVEIK(SEQ ID NO: 30)GACATTCAAATGACGCAGAGTCCCTCCTCACTGAGTGCTAGCGTGGGCGATCGTGTGACAATTACTTGT(SEQ ID NO: 66)CGCGCTAGCCAGTCTATCCGTAATTACCTGAAC(SEQ ID NO: 84)TGGTATCAGCAGAAACCGGGCAAGGCGCCAAAATTGCTGATTTAC(SEQ ID NO: 68)GCAGCATCCCGTCTGCAGTCT(SEQ ID NO: 74)GGTGTACCGTCCCGTTTCTCTGGCAGCGGTTCTGGTACGGATTTTACCCTGACCATCTCAAGCCTCCAGCCTGAAGATTTTGCCACCTATTATTGT(SEQ ID NO: 70)CAGCAATCTTACTCTTCTCCGTGGACG(SEQ ID NO: 77)TTCGGGCAGGGAACTAAAGTGGAAATTAAA(SEQ ID NO: 72)

[0071]

[0072] 3. Production of TREM2-binding antibody protein

[0073] Variable region sequences for eight new human antibodies were obtained and cloned into the animal cell expression vector pcDNA™ 3.4 TOPO vector (ThermoFisher Scientific, Cat. A14697) along with constant region sequences (P01857, P01834).

[0074] To express TREM2-binding antibody proteins, each plasmid DNA was transfected into Expi293 cells as described in the manufacturer's protocol (ExpiFectamine 293 transfection kit, ThermoFisher Scientific). Briefly, 6 × 10 6 After transfection with DNA and ExpiFectamine complex, Expi293 cells / ml were cultured at 37°C under 8% CO2 conditions, and an expression enhancer was added 24 h later. On the second day after transfection, the cells were cultured at 32°C for 6 days, and the culture supernatant containing TREM2-binding antibody protein was collected.

[0075] A Protein A affinity chromatography column (GE Healthcare) was equilibrated with PBS (pH 7.4). The culture supernatant containing each TREM2-binding antibody protein was filtered through a 0.2 μm filter and loaded onto the Protein A affinity chromatography column. After washing the column with PBS (pH 7.4), the TREM2-binding antibody protein was eluted with a 100 mM glycine (pH 3.4) solution. The eluate was neutralized by adding 1 M Tris solution and the buffer was exchanged with PBS. The purified TREM2-binding antibody was confirmed by SDS-PAGE gel analysis (Invitrogen) and SE-HPLC analysis, and the protein concentration was quantified using a Nanodrop 2000C spectrophotometer (Thermo Scientific). Except for TREM2-3-B6, which had a monomer ratio of 88.57% based on SE-HPLC, the remaining seven antibodies were confirmed to have a monomer ratio of over 90% (Fig. 2).

[0076]

[0077] <Example 2> Evaluation of binding affinity of TREM2-binding antibodies to human TREM2

[0078] To quantitatively analyze the binding affinity of the TREM2 binding antibody manufactured in Example 1 to the antigen, K for each antibody was calculated using Biacore. DThe binding affinity for the antigen was measured using the value. The system and sample buffer used was HBS-EP (10 mM HEPES, 150 mM NaCl, 3.4 mM EDTA, 0.005% Polysorbate 20 (v / v)). The antigen with His tag was immobilized on the surface of the CM5 chip by performing the amine coupling procedure according to the manufacturer's protocol of the His capture kit (Cytiva). The antibody protein diluted in HBS-EP buffer was flowed over the antibody-immobilized CM5 chip at a flow rate of 30 μL / min for 2 min for binding and 5 min for dissociation. Next, the antibody protein bound to the antigen was washed by reacting with 10 mM glycine-HCl (pH 1.5) for 60 s. The sensorgram of the antibody was analyzed using Biacore evaluation software. As a result, it was confirmed that all eight types bound to the human TREM2 antigen protein at sub-nanomolar levels or higher (Fig. 3).

[0079]

[0080] <Example 3> Verification of the efficacy of human antibodies

[0081] TREM2 loses its function when the outer part of the cell membrane is cleaved by sheddase such as ADAM10 / 17, and at the same time, the amount of cleaved soluble TREM2 (sTREM2) present in the cell culture medium increases. The antibody disclosed in the present invention can inhibit shedding by binding to TREM2 exposed to the outer part of the cell membrane, and this protective effect was evaluated as a decrease in the amount of sTREM2 present in the culture medium and internal TREM2 (iTREM2) present in the cell, and an increase in the protein amount of membrane TREM2 (mTREM2).

[0082] To evaluate the TREM2 shedding inhibitory effect by the human antibodies specified in the present invention, HEK2393T cells cultured in Dulbecco's Modified Eagle Medium (DMEM) containing 10% fetal bovine serum (FBS) were transfected with polyethylenimine (PEI) to express human TREM2-His and DAP12-V5. After culturing for 8 hours, the cells were replaced with fresh culture medium containing the control (C2 produced in the mouse and human IgG) or each human antibody at a concentration of 20 ug / mL, and further cultured for 16 hours. To confirm the amount of sTREM2 contained in the culture medium, pure culture medium and cell fraction samples (total cell lysate, internal fraction, membrane fraction) were obtained after removing the cells by centrifugation. The whole cell fraction was prepared by dissolving the cells obtained by centrifugation in the lysate (1% Triton X-100, 1X phosphate buffered saline (PBS), 1X protease inhibitor cocktail (PIC)), rotating them in a refrigerator (4℃) for 1 hour, and then centrifuging them to remove the remaining debris to obtain all the intracellular and cell membrane fraction proteins. The intracellular fraction was prepared by dissolving the cells obtained by centrifugation in the storage solution (20 mM Tris, pH 7.0, 1 mM EDTA / EGTA, 1X PIC), keeping them on ice for 30 minutes to fill the inside of the cells with the buffer, and then freezing them in an ultra-low temperature freezer (-80℃) and thawing them to rupture the cells, and then centrifuging them to separate the intracellular fraction from the cell membrane fraction. The proteins of the remaining cell membrane fraction were eluted from the cell membrane using the lysate, and then separated / obtained from the debris by centrifugation.Each fraction obtained was mixed with lithium dodecyl sulfate (LDS) buffer containing a reducing agent to loosen the protein tertiary structure, then separated by size on Bolt™ 4-12% Bis-Tris Plus Gels (ThermoFisher) and transferred to a polyvinylidene difluoride (PVDF) membrane. The PVDF membrane was sequentially reacted with a buffer containing TREM2 antibody (Abcam #ab209814, 0.4 ug / mL) and a secondary antibody (Rockland #18-8816-31, 1 ug / mL, horseradish peroxidase (HRP)-conjugated form), and then treated with a luminol solution to confirm the amount of human TREM2. The intensity of the luminol signal according to the amount of protein was analyzed using the ImageJ program to quantify the amount of protein, and the shedding inhibition effect was evaluated using the following formula (Fig. 4).

[0083] [membrane TREM2 ÷ (soluble TREM2 × internal TREM2)]

[0084]

[0085] Among the human antibodies specified in the present invention, B2, B7, and E10 showed superior inhibitory effects compared to the shedding inhibition of mouse-derived antibody C2, and B1 and F3 showed inhibitory effects similar to the mouse-derived antibody C2. However, A9, G11, and H4 showed somewhat reduced inhibitory effects compared to the shedding inhibition of mouse-derived antibody C2 (Table 2).

[0086]

[0087]

[0088] Antibody-IgGC2A9B1B2B7E10F3G11H4Average0.500.421.000.770.961.161.231.280.930.750.67Standard error0.140.160.030.010.030.110.100.240.170.170.20

[0089]

[0090] While specific aspects of the present invention have been described in detail above, it should be apparent to those skilled in the art that these specific descriptions are merely preferred implementation examples and do not limit the scope of the present invention. Therefore, the substantial scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 selected from the group consisting of an amino acid sequence represented by SEQ ID NO: 2, an amino acid sequence represented by SEQ ID NO: 8, and an amino acid sequence represented by SEQ ID NO: 13, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 selected from the group consisting of an amino acid sequence represented by SEQ ID NO: 4, an amino acid sequence represented by SEQ ID NO: 9, an amino acid sequence represented by SEQ ID NO: 11, an amino acid sequence represented by SEQ ID NO: 14, an amino acid sequence represented by SEQ ID NO: 16, an amino acid sequence represented by SEQ ID NO: 18, an amino acid sequence represented by SEQ ID NO: 20, and an amino acid sequence represented by SEQ ID NO: 22, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 6, an amino acid sequence represented by SEQ ID NO: 10, an amino acid sequence represented by SEQ ID NO: 12, an amino acid sequence represented by SEQ ID NO: 15, an amino acid sequence represented by SEQ ID NO: 17, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, an amino acid sequence represented by SEQ ID NO: 6, an amino acid sequence represented by SEQ ID NO: 10, an amino acid sequence represented by SEQ ID NO: 12, an amino acid sequence represented by SEQ ID NO: 15, an amino acid sequence represented by SEQ ID NO: 17, a heavy chain CDR2 selected from the group consisting of an amino acid sequence represented by SEQ ID NO: 4, an amino acid sequence represented by SEQ ID NO: 9, an amino acid sequence represented by SEQ ID NO: 11, an amino acid sequence represented by SEQ ID NO: 14, an amino acid sequence represented by SE A heavy chain variable region comprising a heavy chain CDR3 selected from the group consisting of an amino acid sequence represented by SEQ ID NO: 19, an amino acid sequence represented by SEQ ID NO: 21, and an amino acid sequence represented by SEQ ID NO: 23, and a heavy chain FR4 comprising an amino acid sequence represented by SEQ ID NO: 7; and A light chain FR1 comprising an amino acid sequence represented by SEQ ID NO: 24, an amino acid sequence represented by SEQ ID NO: 25, an amino acid sequence represented by SEQ ID NO: 31, an amino acid sequence represented by SEQ ID NO: 36, an amino acid sequence represented by SEQ ID NO: 38, and an amino acid sequence represented by SEQ ID NO: 42, a light chain CDR1 selected from the group consisting of a light chain FR2 comprising an amino acid sequence represented by SEQ ID NO: 26, an amino acid sequence represented by SEQ ID NO: 27, an amino acid sequence represented by SEQ ID NO: 32, and an amino acid sequence represented by SEQ ID NO: 34, a light chain FR3 comprising an amino acid sequence represented by SEQ ID NO: 28, an amino acid sequence represented by SEQ ID NO: 29, an amino acid sequence represented by SEQ ID NO: 33, an amino acid sequence represented by SEQ ID NO: 35, an amino acid sequence represented by SEQ ID NO: 37, an amino acid sequence represented by SEQ ID NO: 39, an amino acid sequence represented by SEQ ID NO: 40, and an amino acid sequence represented by SEQ ID NO: 41, and a light chain CDR1 selected from the group consisting of an amino acid sequence represented by SEQ ID NO: 30 A human antibody or antigen-binding fragment thereof that specifically binds to human TREM2 (Triggering receptor expressed on myeloid cells 2) protein, comprising a light chain variable region comprising a light chain FR4 consisting of the amino acid sequence shown.

2. In the first paragraph, the human antibody or antigen-binding fragment thereof that specifically binds to the human TREM2 protein is 1) A heavy chain variable region comprising a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 2, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 4, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 6, and a heavy chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 7; and a light chain variable region comprising a light chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 24, a light chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 25, a light chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 26, a light chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 27, a light chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 28, a light chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 29, and a light chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 30, or 2) A heavy chain variable region comprising a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 8, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 9, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 10, and a heavy chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 7; and a light chain variable region comprising a light chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 24, a light chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 31, a light chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 26, a light chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 32, a light chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 28, a light chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 33, and a light chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 30, or 3) A heavy chain variable region comprising a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 8, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 11, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 12, and a heavy chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 7; and a light chain variable region comprising a light chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 24, a light chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 25, a light chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 26, a light chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 34, a light chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 28, a light chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 35, and a light chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 30, or 4) A heavy chain variable region comprising a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 13, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 14, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 15, and a heavy chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 7; and a light chain variable region comprising a light chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 24, a light chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 36, a light chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 26, a light chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 34, a light chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 28, a light chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 37, and a light chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 30, or 5) A heavy chain variable region comprising a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 2, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 16, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 17, and a heavy chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 7; and a light chain variable region comprising a light chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 24, a light chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 38, a light chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 26, a light chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 32, a light chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 28, a light chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 39, and a light chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 30, or 6) A heavy chain variable region comprising a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 2, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 18, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 19, and a heavy chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 7; and a light chain variable region comprising a light chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 24, a light chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 25, a light chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 26, a light chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 34, a light chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 28, a light chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 40, and a light chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 30, or 7) A heavy chain variable region comprising a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 8, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 20, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 21, and a heavy chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 7; and a light chain variable region comprising a light chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 24, a light chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 25, a light chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 26, a light chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 32, a light chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 28, a light chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 41, and a light chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 30, or 8) A heavy chain variable region comprising a heavy chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 1, a heavy chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 8, a heavy chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 3, a heavy chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 22, a heavy chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 5, a heavy chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 23, and a heavy chain FR4 consisting of an amino acid sequence represented by SEQ ID NO: 7; A human antibody or antigen-binding fragment thereof, characterized in that it comprises a light chain variable region comprising a light chain FR1 consisting of an amino acid sequence represented by SEQ ID NO: 24, a light chain CDR1 consisting of an amino acid sequence represented by SEQ ID NO: 42, a light chain FR2 consisting of an amino acid sequence represented by SEQ ID NO: 26, a light chain CDR2 consisting of an amino acid sequence represented by SEQ ID NO: 32, a light chain FR3 consisting of an amino acid sequence represented by SEQ ID NO: 28, a light chain CDR3 consisting of an amino acid sequence represented by SEQ ID NO: 35, and a light chain FR4 consisting of an amino acid sequence represented by SEQ ID NO:

30.

3. A nucleic acid molecule encoding a human antibody or antigen-binding fragment thereof of claim 1 or 2.

4. A recombinant expression vector comprising the nucleic acid molecule of paragraph 3.

5. Cells isolated by transformation with the recombinant expression vector of Article 4.

6. A composition for detecting human TREM2 antigen comprising the human antibody of claim 1 or 2 or an antigen-binding fragment thereof as an active ingredient.

7. A composition for diagnosing Alzheimer's disease comprising the human antibody of claim 1 or 2 or an antigen-binding fragment thereof as an active ingredient.

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