Antibodies against human immunodeficiency virus type 1 p24 and type 2 p26, and their applications

Abstract

This invention provides antibodies for an immunoassay method that can simultaneously detect HIV-1 and HIV-2. [Solution] The present invention provides antibodies or antigen-binding fragments thereof that can specifically bind to the p24 protein of human immunodeficiency virus type 1 and the p26 protein of human immunodeficiency virus type 2, and provides antibody pair combinations, kits, and related applications. By using the above antibody pair for immunodetection, the antigens of HIV-1 type p24 and HIV-2 type p26 can be detected simultaneously, and have the advantage of having a lower detection limit.

Description

Technical Field

[0001] (Cross - reference to related applications) The present invention is proposed based on a Chinese patent application with an application number of 202411507204.4 and an application date of October 25, 2024, and claims the priority of this Chinese patent application, and incorporates all the contents of this Chinese patent application into this application by reference.

[0002] (Technical Field) The present invention relates to the field of biomedical technology, specifically to anti - human immunodeficiency virus type 1 p24 and type 2 p26 antibodies and their uses.

Background Art

[0003] Human immunodeficiency virus (HIV) is a human retrovirus that causes a series of diseases such as acquired immunodeficiency syndrome (AIDS) and AIDS - related complex (ARC). Currently, there is a lack of effective vaccines or effective treatment methods for these diseases. Therefore, early diagnosis of HIV by an effective HIV - specific detection method is very important.

[0004] There are two types of HIV, HIV - 1 and HIV - 2. Their genetic protein compositions are the same 15 genetic proteins (one gene is different, namely VPU and VPX respectively), but the heterogeneity of the amino acid sequences of the two types still reaches 40 - 60%, especially significant in the outer membrane parts of the two types. The infectivity, pathogenicity, and epidemic intensity of HIV - 1 and HIV - 2 are different. Currently, HIV - 1 causes a widespread epidemic of AIDS worldwide, and HIV - 2 mainly occurs in West African countries, but has a tendency to spread around the world in recent years. In recent years, infections caused by HIV - 2 are not uncommon in China either.

[0005] Therefore, those skilled in the art hope to develop an immunoassay method that can detect HIV - 1 and HIV - 2 simultaneously.

Summary of the Invention

Problems to be Solved by the Invention

[0006] In view of the above, the present invention discloses anti-human immunodeficiency virus type 1 p24 and type 2 p26 antibodies and their uses. [Means for solving the problem]

[0007] In a first aspect, the present invention provides an antibody or antigen-binding fragment thereof that specifically binds to the p24 protein of human immunodeficiency virus type 1 and the p26 protein of human immunodeficiency virus type 2, wherein the antibody or antigen-binding fragment comprises a heavy chain variable region including HCDR1, HCDR2, and HCDR3, and a light chain variable region including the amino acid sequences of LCDR1, LCDR2, and LCDR3. The amino acid sequence of HCDR1 is selected from SEQ ID NO: 1, 7, 13, 19, 25, 31, 37 or its variants; the amino acid sequence of HCDR2 is selected from SEQ ID NO: 2, 8, 14, 20, 26, 32, 38 or its variants; and the amino acid sequence of HCDR3 is selected from SEQ ID NO: 3, 9, 15, 21, 27, 33, 39 or its variants. The amino acid sequence of LCDR1 is selected from SEQ ID NO: 4, 10, 16, 22, 28, 34, 40 or their variants; the amino acid sequence of LCDR2 is selected from SEQ ID NO: 5, 11, 17, 23, 29, 35, 41 or their variants; and the amino acid sequence of LCDR3 is selected from SEQ ID NO: 6, 12, 18, 24, 30, 36, 42 or their variants. The variant includes an amino acid mutation compared to the amino acid sequence from which it is derived, the amino acid mutation being a substitution, deletion or addition of one or more amino acids (for example, a substitution, deletion or addition of one, two, three, four or five amino acids), and the variant has at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99% identity with the amino acid sequence from which it is derived.

[0008] In some embodiments, the substitution is a conservative substitution.

[0009] In some embodiments, the amino acid sequences of HCDR1, HCDR2, and HCDR3 are selected from the following group: The amino acid sequence of HCDR1 is SEQ ID NO:1, the amino acid sequence of HCDR2 is SEQ ID NO:2, and the amino acid sequence of HCDR3 is SEQ ID NO:3. The amino acid sequence of HCDR1 is SEQ ID NO:7, the amino acid sequence of HCDR2 is SEQ ID NO:8, and the amino acid sequence of HCDR3 is SEQ ID NO:9. The amino acid sequence of HCDR1 is SEQ ID NO:13, the amino acid sequence of HCDR2 is SEQ ID NO:14, and the amino acid sequence of HCDR3 is SEQ ID NO:15. The amino acid sequence of HCDR1 is SEQ ID NO:19, the amino acid sequence of HCDR2 is SEQ ID NO:20, and the amino acid sequence of HCDR3 is SEQ ID NO:21. The amino acid sequence of HCDR1 is SEQ ID NO:25, the amino acid sequence of HCDR2 is SEQ ID NO:26, and the amino acid sequence of HCDR3 is SEQ ID NO:27. The amino acid sequence of HCDR1 is SEQ ID NO:31, the amino acid sequence of HCDR2 is SEQ ID NO:32, and the amino acid sequence of HCDR3 is SEQ ID NO:33; or, The amino acid sequence of HCDR1 is SEQ ID NO:37, the amino acid sequence of HCDR2 is SEQ ID NO:38, and the amino acid sequence of HCDR3 is SEQ ID NO:39. The amino acid sequences of LCDR1, LCDR2, and LCDR3 are selected from one of the following groups: The amino acid sequence of LCDR1 is SEQ ID NO:4, the amino acid sequence of LCDR2 is SEQ ID NO:5, and the amino acid sequence of LCDR3 is SEQ ID NO:6. The amino acid sequence of LCDR1 is SEQ ID NO:10, the amino acid sequence of LCDR2 is SEQ ID NO:11, and the amino acid sequence of LCDR3 is SEQ ID NO:12. The amino acid sequence of LCDR1 is SEQ ID NO:16, the amino acid sequence of LCDR2 is SEQ ID NO:17, and the amino acid sequence of LCDR3 is SEQ ID NO:18. The amino acid sequence of LCDR1 is SEQ ID NO:22, the amino acid sequence of LCDR2 is SEQ ID NO:23, and the amino acid sequence of LCDR3 is SEQ ID NO:24. The amino acid sequence of LCDR1 is SEQ ID NO:28, the amino acid sequence of LCDR2 is SEQ ID NO:29, and the amino acid sequence of LCDR3 is SEQ ID NO:30. The amino acid sequence of LCDR1 is SEQ ID NO:34, the amino acid sequence of LCDR2 is SEQ ID NO:35, and the amino acid sequence of LCDR3 is SEQ ID NO:36; or, The amino acid sequence of LCDR1 is SEQ ID NO:40, the amino acid sequence of LCDR2 is SEQ ID NO:41, and the amino acid sequence of LCDR3 is SEQ ID NO:42.

[0010] In some embodiments, the antibody or its antigen-binding fragment comprises a heavy chain variable region including HCDR1, HCDR2, and HCDR3, and a light chain variable region including the amino acid sequences of LCDR1, LCDR2, and LCDR3. Here, the amino acid sequence of HCDR1 is SEQ ID NO:1, the amino acid sequence of HCDR2 is SEQ ID NO:2, the amino acid sequence of HCDR3 is SEQ ID NO:3, the amino acid sequence of LCDR1 is SEQ ID NO:4, the amino acid sequence of LCDR2 is SEQ ID NO:5, the amino acid sequence of LCDR3 is SEQ ID NO:6, or The amino acid sequence of HCDR1 is SEQ ID NO:7, the amino acid sequence of HCDR2 is SEQ ID NO:8, the amino acid sequence of HCDR3 is SEQ ID NO:9, the amino acid sequence of LCDR1 is SEQ ID NO:10, the amino acid sequence of LCDR2 is SEQ ID NO:11, the amino acid sequence of LCDR3 is SEQ ID NO:12, or The amino acid sequence of HCDR1 is SEQ ID NO:13, the amino acid sequence of HCDR2 is SEQ ID NO:14, the amino acid sequence of HCDR3 is SEQ ID NO:15, the amino acid sequence of LCDR1 is SEQ ID NO:16, the amino acid sequence of LCDR2 is SEQ ID NO:17, the amino acid sequence of LCDR3 is SEQ ID NO:18, or The amino acid sequence of HCDR1 is SEQ ID NO:19, the amino acid sequence of HCDR2 is SEQ ID NO:20, the amino acid sequence of HCDR3 is SEQ ID NO:21, the amino acid sequence of LCDR1 is SEQ ID NO:22, the amino acid sequence of LCDR2 is SEQ ID NO:23, the amino acid sequence of LCDR3 is SEQ ID NO:24, or The amino acid sequence of HCDR1 is SEQ ID NO:25, the amino acid sequence of HCDR2 is SEQ ID NO:26, the amino acid sequence of HCDR3 is SEQ ID NO:27, the amino acid sequence of LCDR1 is SEQ ID NO:28, the amino acid sequence of LCDR2 is SEQ ID NO:29, the amino acid sequence of LCDR3 is SEQ ID NO:30, or The amino acid sequence of HCDR1 is SEQ ID NO:31, the amino acid sequence of HCDR2 is SEQ ID NO:32, the amino acid sequence of HCDR3 is SEQ ID NO:33, the amino acid sequence of LCDR1 is SEQ ID NO:34, the amino acid sequence of LCDR2 is SEQ ID NO:35, the amino acid sequence of LCDR3 is SEQ ID NO:36, or The amino acid sequence of HCDR1 is SEQ ID NO:37, the amino acid sequence of HCDR2 is SEQ ID NO:38, the amino acid sequence of HCDR3 is SEQ ID NO:39, the amino acid sequence of LCDR1 is SEQ ID NO:40, the amino acid sequence of LCDR2 is SEQ ID NO:41, and the amino acid sequence of LCDR3 is SEQ ID NO:42.

[0011] In some embodiments, the antibody is a full-length antibody, a Fab fragment, a Fab' fragment, an F(ab')2 fragment, a double-stranded Fv fragment, or a single-stranded Fv fragment.

[0012] In some embodiments, the antibody is a monoclonal antibody.

[0013] In some embodiments, the type of the antibody or its antigen-binding fragment is IgG, IgM, IgE, IgD, or IgA.

[0014] In some embodiments, the antibody is a mouse-derived antibody, a rabbit-derived antibody, or a humanized antibody.

[0015] In some embodiments, the antibody includes a constant region.

[0016] In some embodiments, the steady-state region includes a heavy chain steady-state region and / or a light chain steady-state region.

[0017] In some embodiments, the constant region includes a mouse constant region, a rat constant region, a rabbit constant region, a sheep constant region, a monkey constant region, or a human constant region.

[0018] In some embodiments, the heavy chain constant region is the heavy chain constant region of IgG1, IgG2, IgG3 or IgG4.

[0019] In some embodiments, the light chain constant region is a κ or λ light chain constant region.

[0020] In some embodiments, the antibody or antigen-binding fragment thereof is further conjugated with a detection marker, and the detection marker comprises at least one selected from the group consisting of a radioactive marker, a fluorescent marker, a chemiluminescent marker, biotin, colloidal gold, an electrochemiluminescent marker, a quantum dot, or an enzyme.

[0021] In some embodiments, the antibody or antigen-binding fragment thereof is deposited with VKPM and produced by a hybridoma cell line with the accession number VKPM H-227.

[0022] In some embodiments, the antibody or antigen-binding fragment thereof is deposited with VKPM and produced by a hybridoma cell line with the accession number VKPM H-228.

[0023] In some embodiments, the antibody or antigen-binding fragment thereof is deposited with VKPM and produced by plasmids in Escherichia coli with the accession number VKPM B-15024 and plasmids in Escherichia coli with the accession number VKPM B-15025.

[0024] In some embodiments, the antibody or antigen-binding fragment thereof is deposited with VKPM and produced by plasmids in Escherichia coli with the accession number VKPM B-15026 and plasmids in Escherichia coli with the accession number VKPM B-15027.

[0025] In some embodiments, the antibody or its antigen-binding fragment is deposited with VKPM and produced by plasmids in E. coli with accession number VKPM B-15028 and plasmids in E. coli with accession number VKPM B-15029.

[0026] In some embodiments, the antibody or its antigen-binding fragment is deposited with VKPM and produced by plasmids in E. coli with accession number VKPM B-15030 and plasmids in E. coli with accession number VKPM B-15031.

[0027] In some embodiments, the antibody or its antigen-binding fragment is deposited with VKPM and produced by plasmids in E. coli with accession number VKPM B-15032 and plasmids in E. coli with accession number VKPM B-15033.

[0028] A second aspect of the present invention provides an isolated polynucleotide encoding an antibody or an antigen-binding fragment thereof as described in the first aspect of the present invention.

[0029] A third aspect of the present invention provides a vector comprising the isolated polynucleotide described in the second aspect of the present invention.

[0030] A fourth aspect of the present invention provides a host cell containing an isolated polynucleotide as described in the second aspect of the present invention, or a vector as described in the third aspect of the present invention.

[0031] In a fifth aspect of the present invention, an antibody pair comprising a capture antibody and a detection antibody is provided, wherein at least one of the capture antibody and the detection antibody is selected from the antibody or its antigen-binding fragment described in the first aspect of the present invention.

[0032] In some embodiments, the capture antibody and the detection antibody are each independently selected from the antibody or antigen-binding fragment described in the first aspect of the present invention, and the capture antibody and the detection antibody are not the same.

[0033] In some embodiments, the antibody pair is selected from any of the following groups (i) to (vi): (i) A capture antibody comprising HCDR1 with amino acid sequence SEQ ID NO:7, HCDR2 with amino acid sequence SEQ ID NO:8, HCDR3 with amino acid sequence SEQ ID NO:9, LCDR1 with amino acid sequence SEQ ID NO:10, LCDR2 with amino acid sequence SEQ ID NO:11, and LCDR3 with amino acid sequence SEQ ID NO:12 (in some examples, the capture antibody is p24_138), and A detection antibody selected from one of the following groups: A detection antibody comprising HCDR1 with amino acid sequence SEQ ID NO:37, HCDR2 with amino acid sequence SEQ ID NO:38, HCDR3 with amino acid sequence SEQ ID NO:39, LCDR1 with amino acid sequence SEQ ID NO:40, LCDR2 with amino acid sequence SEQ ID NO:41, and LCDR3 with amino acid sequence SEQ ID NO:42 (in some examples, the detection antibody is p24_rec_252); A detection antibody comprising HCDR1 with amino acid sequence SEQ ID NO:1, HCDR2 with amino acid sequence SEQ ID NO:2, HCDR3 with amino acid sequence SEQ ID NO:3, LCDR1 with amino acid sequence SEQ ID NO:4, LCDR2 with amino acid sequence SEQ ID NO:5, and LCDR3 with amino acid sequence SEQ ID NO:6 (in some examples, the detection antibody is p24_113); A detection antibody containing HCDR1 with amino acid sequence SEQ ID NO:31, HCDR2 with amino acid sequence SEQ ID NO:32, HCDR3 with amino acid sequence SEQ ID NO:33, LCDR1 with amino acid sequence SEQ ID NO:34, LCDR2 with amino acid sequence SEQ ID NO:35, and LCDR3 with amino acid sequence SEQ ID NO:36 (in some examples, the detection antibody is p24_rec_179); A detection antibody containing HCDR1 with amino acid sequence SEQ ID NO:25, HCDR2 with amino acid sequence SEQ ID NO:26, HCDR3 with amino acid sequence SEQ ID NO:27, LCDR1 with amino acid sequence SEQ ID NO:28, LCDR2 with amino acid sequence SEQ ID NO:29, and LCDR3 with amino acid sequence SEQ ID NO:30 (in some examples, the detection antibody is p24_rec_151); A detection antibody comprising HCDR1 with amino acid sequence SEQ ID NO:13, HCDR2 with amino acid sequence SEQ ID NO:14, HCDR3 with amino acid sequence SEQ ID NO:15, LCDR1 with amino acid sequence SEQ ID NO:16, LCDR2 with amino acid sequence SEQ ID NO:17, and LCDR3 with amino acid sequence SEQ ID NO:18 (in some examples, the detection antibody is p24_rec_131); or, A detection antibody containing HCDR1 with amino acid sequence SEQ ID NO:19, HCDR2 with amino acid sequence SEQ ID NO:20, HCDR3 with amino acid sequence SEQ ID NO:21, LCDR1 with amino acid sequence SEQ ID NO:22, LCDR2 with amino acid sequence SEQ ID NO:23, and LCDR3 with amino acid sequence SEQ ID NO:24 (in some examples, the detection antibody is p24_rec_140); (ii) A capture antibody comprising HCDR1 with amino acid sequence SEQ ID NO:25, HCDR2 with amino acid sequence SEQ ID NO:26, HCDR3 with amino acid sequence SEQ ID NO:27, LCDR1 with amino acid sequence SEQ ID NO:28, LCDR2 with amino acid sequence SEQ ID NO:29, and LCDR3 with amino acid sequence SEQ ID NO:30 (in some examples, the capture antibody is p24_rec_151), and A detection antibody selected from one of the following groups: A detection antibody comprising HCDR1 with amino acid sequence SEQ ID NO:37, HCDR2 with amino acid sequence SEQ ID NO:38, HCDR3 with amino acid sequence SEQ ID NO:39, LCDR1 with amino acid sequence SEQ ID NO:40, LCDR2 with amino acid sequence SEQ ID NO:41, and LCDR3 with amino acid sequence SEQ ID NO:42 (in some examples, the detection antibody is p24_rec_252); A detection antibody containing HCDR1 with amino acid sequence SEQ ID NO:19, HCDR2 with amino acid sequence SEQ ID NO:20, HCDR3 with amino acid sequence SEQ ID NO:21, LCDR1 with amino acid sequence SEQ ID NO:22, LCDR2 with amino acid sequence SEQ ID NO:23, and LCDR3 with amino acid sequence SEQ ID NO:24 (in some examples, the detection antibody is p24_rec_140); A detection antibody (in some examples, the detection antibody is p24_rec_179) containing HCDR1 with amino acid sequence SEQ ID NO:31, HCDR2 with amino acid sequence SEQ ID NO:32, HCDR3 with amino acid sequence SEQ ID NO:33, LCDR1 with amino acid sequence SEQ ID NO:34, LCDR2 with amino acid sequence SEQ ID NO:35, and LCDR3 with amino acid sequence SEQ ID NO:36, or A detection antibody containing HCDR1 with amino acid sequence SEQ ID NO:13, HCDR2 with amino acid sequence SEQ ID NO:14, HCDR3 with amino acid sequence SEQ ID NO:15, LCDR1 with amino acid sequence SEQ ID NO:16, LCDR2 with amino acid sequence SEQ ID NO:17, and LCDR3 with amino acid sequence SEQ ID NO:18 (in some examples, the detection antibody is p24_rec_131); (iii) A capture antibody comprising HCDR1 with amino acid sequence SEQ ID NO:31, HCDR2 with amino acid sequence SEQ ID NO:32, HCDR3 with amino acid sequence SEQ ID NO:33, LCDR1 with amino acid sequence SEQ ID NO:34, LCDR2 with amino acid sequence SEQ ID NO:35, and LCDR3 with amino acid sequence SEQ ID NO:36 (in some examples, the capture antibody is p24_rec_179), and A detection antibody selected from one of the following groups: A detection antibody comprising HCDR1 with amino acid sequence SEQ ID NO:37, HCDR2 with amino acid sequence SEQ ID NO:38, HCDR3 with amino acid sequence SEQ ID NO:39, LCDR1 with amino acid sequence SEQ ID NO:40, LCDR2 with amino acid sequence SEQ ID NO:41, and LCDR3 with amino acid sequence SEQ ID NO:42 (in some examples, the detection antibody is p24_rec_252); or, A detection antibody comprising HCDR1 with amino acid sequence SEQ ID NO:1, HCDR2 with amino acid sequence SEQ ID NO:2, HCDR3 with amino acid sequence SEQ ID NO:3, LCDR1 with amino acid sequence SEQ ID NO:4, LCDR2 with amino acid sequence SEQ ID NO:5, and LCDR3 with amino acid sequence SEQ ID NO:6 (in some examples, the detection antibody is p24_113); (iv) A capture antibody comprising HCDR1 with amino acid sequence SEQ ID NO:19, HCDR2 with amino acid sequence SEQ ID NO:20, HCDR3 with amino acid sequence SEQ ID NO:21, LCDR1 with amino acid sequence SEQ ID NO:22, LCDR2 with amino acid sequence SEQ ID NO:23, and LCDR3 with amino acid sequence SEQ ID NO:24 (in some examples, the capture antibody is p24_rec_140), and A detection antibody comprising HCDR1 with amino acid sequence SEQ ID NO:37, HCDR2 with amino acid sequence SEQ ID NO:38, HCDR3 with amino acid sequence SEQ ID NO:39, LCDR1 with amino acid sequence SEQ ID NO:40, LCDR2 with amino acid sequence SEQ ID NO:41, and LCDR3 with amino acid sequence SEQ ID NO:42 (in some examples, the detection antibody is p24_rec_252); (v) A capture antibody comprising HCDR1 with amino acid sequence SEQ ID NO:13, HCDR2 with amino acid sequence SEQ ID NO:14, HCDR3 with amino acid sequence SEQ ID NO:15, LCDR1 with amino acid sequence SEQ ID NO:16, LCDR2 with amino acid sequence SEQ ID NO:17, and LCDR3 with amino acid sequence SEQ ID NO:18 (in some examples, the capture antibody is p24_rec_131), and A detection antibody comprising HCDR1 with amino acid sequence SEQ ID NO:37, HCDR2 with amino acid sequence SEQ ID NO:38, HCDR3 with amino acid sequence SEQ ID NO:39, LCDR1 with amino acid sequence SEQ ID NO:40, LCDR2 with amino acid sequence SEQ ID NO:41, and LCDR3 with amino acid sequence SEQ ID NO:42 (in some examples, the detection antibody is p24_rec_252); (vi) A capture antibody comprising HCDR1 with amino acid sequence SEQ ID NO:1, HCDR2 with amino acid sequence SEQ ID NO:2, HCDR3 with amino acid sequence SEQ ID NO:3, LCDR1 with amino acid sequence SEQ ID NO:4, LCDR2 with amino acid sequence SEQ ID NO:5, and LCDR3 with amino acid sequence SEQ ID NO:6 (in some examples, the capture antibody is p24_113) and A detection antibody selected from one of the following groups: A detection antibody containing HCDR1 with amino acid sequence SEQ ID NO:25, HCDR2 with amino acid sequence SEQ ID NO:26, HCDR3 with amino acid sequence SEQ ID NO:27, LCDR1 with amino acid sequence SEQ ID NO:28, LCDR2 with amino acid sequence SEQ ID NO:29, and LCDR3 with amino acid sequence SEQ ID NO:30 (in some examples, the detection antibody is p24_rec_151); A detection antibody comprising HCDR1 with amino acid sequence SEQ ID NO:13, HCDR2 with amino acid sequence SEQ ID NO:14, HCDR3 with amino acid sequence SEQ ID NO:15, LCDR1 with amino acid sequence SEQ ID NO:16, LCDR2 with amino acid sequence SEQ ID NO:17, and LCDR3 with amino acid sequence SEQ ID NO:18 (in some examples, the detection antibody is p24_rec_131); or, A detection antibody containing HCDR1 with amino acid sequence SEQ ID NO:19, HCDR2 with amino acid sequence SEQ ID NO:20, HCDR3 with amino acid sequence SEQ ID NO:21, LCDR1 with amino acid sequence SEQ ID NO:22, LCDR2 with amino acid sequence SEQ ID NO:23, and LCDR3 with amino acid sequence SEQ ID NO:24 (in some examples, the detection antibody is p24_rec_140).

[0034] In some embodiments, the antibody pair is selected from any of the following groups (a) to (f): (a) A capture antibody produced by a hybridoma cell line with accession number VKPM H-227 deposited with VKPM (in some examples, the capture antibody is p24_138), and A detection antibody selected from one of the following groups: • Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15032 and plasmids in E. coli with accession number VKPM B-15033, deposited with VKPM (in some examples, the detection antibody is p24_rec_252); • Detection antibody produced by the hybridoma cell line with accession number VKPM H-228 deposited with VKPM (in some examples, the detection antibody is p24_113); • Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15030 and plasmids in E. coli with accession number VKPM B-15031, deposited with VKPM (in some examples, the detection antibody is p24_rec_179); • Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15028 and plasmids in E. coli with accession number VKPM B-15029, deposited with VKPM (in some examples, the detection antibody is p24_rec_151); • Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15024 and plasmids in E. coli with accession number VKPM B-15025, deposited with VKPM (in some examples, the detection antibody is p24_rec_131); or, • Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15026 and plasmids in E. coli with accession number VKPM B-15027, deposited with VKPM (in some examples, the detection antibody is p24_rec_140); (b) A capture antibody produced by plasmids in Escherichia coli with accession number VKPM B-15028 and plasmids in Escherichia coli with accession number VKPM B-15029, deposited with VKPM (in some examples, the capture antibody is p24_rec_151), and A detection antibody selected from one of the following groups: • Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15032 and plasmids in E. coli with accession number VKPM B-15033, deposited with VKPM (in some examples, the detection antibody is p24_rec_252); • Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15026 and plasmids in E. coli with accession number VKPM B-15027, deposited with VKPM (in some examples, the detection antibody is p24_rec_140); • Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15030 and plasmids in E. coli with accession number VKPM B-15031, deposited with VKPM (in some examples, the detection antibody is p24_rec_179); or, • Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15024 and plasmids in E. coli with accession number VKPM B-15025, deposited with VKPM (in some examples, the detection antibody is p24_rec_131); (c) A capture antibody produced by plasmids in Escherichia coli with accession number VKPM B-15030 and plasmids in Escherichia coli with accession number VKPM B-15031, deposited with VKPM (in some examples, the capture antibody is p24_rec_179), and A detection antibody selected from one of the following groups: • Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15032 and plasmids in E. coli with accession number VKPM B-15033, deposited with VKPM (in some examples, the detection antibody is p24_rec_252); or, • Detection antibody produced by the hybridoma cell line with accession number VKPM H-228 deposited with VKPM (in some examples, the detection antibody is p24_113); (d) A capture antibody produced by plasmids in Escherichia coli with accession number VKPM B-15026 and plasmids in Escherichia coli with accession number VKPM B-15027, deposited with VKPM (in some examples, the capture antibody is p24_rec_140), and A detection antibody produced by plasmids in E. coli with accession number VKPM B-15032 and plasmids in E. coli with accession number VKPM B-15033, deposited with VKPM (in some examples, the detection antibody is p24_rec_252); (e) A capture antibody produced by plasmids in Escherichia coli with accession number VKPM B-15024 and plasmids in Escherichia coli with accession number VKPM B-15025, deposited with VKPM (in some examples, the capture antibody is p24_rec_131), and A detection antibody produced by plasmids in E. coli with accession number VKPM B-15032 and plasmids in E. coli with accession number VKPM B-15033, deposited with VKPM (in some examples, the detection antibody is p24_rec_252); (f) A capture antibody produced by a hybridoma cell line with accession number VKPM H-228 deposited with VKPM (in some examples, the capture antibody is p24_113), and A detection antibody selected from one of the following groups: • Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15028 and plasmids in E. coli with accession number VKPM B-15029, deposited with VKPM (in some examples, the detection antibody is p24_rec_151); • Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15024 and plasmids in E. coli with accession number VKPM B-15025, deposited with VKPM (in some examples, the detection antibody is p24_rec_131); or, Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15026 and plasmids in E. coli with accession number VKPM B-15027, deposited with VKPM (in some examples, the detection antibody is p24_rec_140).

[0035] A sixth aspect of the present invention provides a kit comprising an antibody or its antigen-binding fragment as described in the first aspect of the present invention, or an antibody pair as described in the fifth aspect of the present invention.

[0036] A seventh aspect of the present invention provides a method for detecting human immunodeficiency virus, the method comprising performing detection on a sample using an antibody or antigen-binding fragment thereof as described in the first aspect of the present invention, or an antibody pair as described in the fifth aspect of the present invention.

[0037] In some embodiments, the human immunodeficiency virus includes human immunodeficiency virus type 1 and human immunodeficiency virus type 2.

[0038] An eighth aspect of the present invention provides a method for assisting in the diagnosis of acquired immunodeficiency syndrome (AIDS) and AIDS-related syndromes (ARC), the method comprising detection of an antibody or its antigen-binding fragment described in the first aspect of the present invention, or an antibody-paired sample described in the fifth aspect of the present invention.

[0039] The above description is merely an outline of the technical solutions of the present invention, and the technical means of the present invention can be implemented according to the specifications for a clearer understanding. Furthermore, in order to make the above and other objectives, features, and advantages of the present invention clearer and easier to understand, specific embodiments of the present invention are illustrated below. [Brief explanation of the drawing]

[0040] [Figure 1] This figure shows the SEC chromatography analysis results for antibody p24_113. [Figure 2] This figure shows the SEC chromatography analysis results for antibody p24_138. [Figure 3] This figure shows the SEC chromatography analysis results for the antibody p24_rec_131. [Figure 4] This figure shows the SEC chromatography analysis results of the antibody p24_rec_140. [Figure 5] This figure shows the SEC chromatography analysis results of the antibody p24_rec_151. [Figure 6] This figure shows the SEC chromatography analysis results for the antibody p24_rec_179. [Figure 7] This figure shows the SEC chromatography analysis results for the antibody p24_rec_252. [Modes for carrying out the invention]

[0041] By reading the detailed description of the following preferred embodiments, various other advantages and beneficial effects will become apparent to those skilled in the art. The drawings are used solely to illustrate preferred embodiments and are not intended to limit the invention.

[0042] Illustrative embodiments of the present invention will be described in more detail below with reference to the drawings. While illustrative embodiments of the present invention are illustrated, it should be understood that the present invention can be realized in various forms and should not be limited to the embodiments described herein. Rather, these embodiments are provided so as to allow for a more complete understanding of the present invention and to fully convey the scope of the invention to those skilled in the art.

[0043] In this invention, unless otherwise specified, scientific and technical terms used herein have the meanings that are ordinarily understood by those skilled in the art. Furthermore, the laboratory procedure steps in cell culture, molecular genetics, nucleic acid chemistry, and immunology used herein are all conventional steps widely used in their respective fields. At the same time, to better understand this invention, definitions and explanations of relevant terms are provided below.

[0044] As used herein, the term “antibody” refers to an immunoglobulin molecule that specifically binds to a target via at least one antigen recognition site located within the variable region of the immunoglobulin molecule. As used herein, “antibody” includes not only complete (i.e., full-length) antibodies, but also their antigen-binding fragments (e.g., Fab, Fab', F(ab')2, Fv, scFv, Fd, CDR fragments), their variants, fusion proteins containing the antibody portion, humanized antibodies, chimeric antibodies, diabodies, linear antibodies, single-chain antibodies, multispecific antibodies (e.g., bispecific antibodies), and modified configurations of any other immunoglobulin molecule containing an antigen recognition site having a desired specificity, as well as glycosylated variants of antibodies, amino acid sequence variants of antibodies, and covalently modified antibodies. Antibodies may originate from any mammal, including but not limited to humans, monkeys, pigs, horses, rabbits, dogs, cats, rats, and mice, or from other animals such as birds (e.g., chickens), fish (e.g., sharks), and camelids (e.g., llamas).

[0045] Typically, a complete or full-length antibody contains two heavy chains and two light chains. Each heavy chain contains a heavy chain variable region (VH) and a heavy chain constant region (CH), and each light chain contains a light chain variable region (VL) and a light chain constant region (CL). A full-length antibody may be any type of antibody, such as IgD, IgE, IgG, IgA, or IgM (or one of the subclasses above), but the antibody does not need to belong to a specific class.

[0046] Based on the antibody amino acid sequence of the heavy chain's constant region, immunoglobulins can be classified into different classes. Typically, immunoglobulins have five main classes: IgA, IgD, IgE, IgG, and IgM. Some of these classes can be further classified into subclasses, such as IgG1, IgG2, IgG3, IgG4, IgA1, and IgA2.

[0047] As used herein, the term “specifically binding” refers to a non-random binding reaction between two molecules, such as the binding of an antibody to an antigenic epitope.

[0048] As used herein, the terms “antigen-binding fragment” or “antigen-binding moiety” refer to a part or region of a complete antibody molecule responsible for binding to an antigen. The antigen-binding moiety includes a heavy chain variable region (VH), a light chain variable region (VL), or both. Each of the VH and VL typically includes three complementarity-determining regions: CDR1, CDR2, and CDR3.

[0049] As is well known to those skilled in the art, the complementarity-determining regions (CDRs, usually CDR1, CDR2, and CDR3) are the regions that have the greatest influence on the affinity and specificity of antibodies within the variable region. For the variable region amino acid sequence of a given antibody, the CDR amino acid sequence within the variable region amino acid sequence can be analyzed by various methods.

[0050] In this specification, the CDR sequences of the heavy chain variable region and the light chain variable region are defined by the Kabat numbering system, where “Kabat numbering system” refers to the EU index by Kabat et al. (see, for example, Kabat, Elvin A., et al. Sequences of Proteins of Immunological Interest. 5th ed. US Dept. of Health and Human Services, Public Health Service, National Institutes of Health, 1991.).

[0051] As used herein, the term “isolated polynucleotide” means a polynucleotide that is (i) isolated from its natural environment, (ii) amplified by polymerase chain reaction, and / or (iii) synthesized in whole or in part, and may include single- or double-stranded polymers of deoxyribonucleotides or ribonucleotide bases, and may include DNA and RNA molecules, both sense and antisense strands. This term includes cDNA, genomic DNA, mRNA, and recombinant DNA. Isolated polynucleotides may consist of an entire gene or a portion thereof.

[0052] As used herein, the term “vector” refers to a construct capable of delivering one or more target genes or sequences to a host cell, and preferably expressing them therein. Examples of vectors include, but are not limited to, viral vectors, naked DNA or RNA expression vectors, plasmids, cosmid or phage vectors, DNA or RNA expression vectors associated with cationic condensers, liposome-encapsulated DNA or RNA expression vectors, and certain eukaryotic cells such as production cells.

[0053] As used herein, the term “host cell” refers to a cell containing a target protein of interest (e.g., an antibody or its antigen-binding fragment provided in any embodiment of the present invention). The target protein (e.g., an antibody or its antigen-binding fragment provided in any embodiment of the present invention) may be encoded by a polynucleotide, preferably by an isolated polynucleotide. The polynucleotide may be present in the host cell in the following forms: (i) freely dispersed by itself, (ii) incorporated into a recombinant vector, or (iii) incorporated into the genome or mitochondrial DNA of the host cell. The host cell may be used to amplify and express the polynucleotide encoding the target protein of interest (e.g., an antibody or its antigen-binding fragment provided in any embodiment of the present invention). In specific embodiments, the host cell may be selected from microbial host cells such as bacterial or yeast host cells, plant host cells, insect host cells, or mammalian host cells.

[0054] As used herein, the term “detection marker” refers to a marker that can be detected directly or under certain conditions (e.g., by providing light irradiation conditions, adding a chromogenic reagent, an enzyme, etc.). The detection marker is directly or indirectly bound to the antibody or its antigen-binding fragment of the present invention via covalent or non-covalent bonds. The detection marker theoretically has no effect, or only a small effect, on the protein structure, function, and activity of the antibody or its antigen-binding fragment. In some embodiments, the detection marker does not affect the function of the antibody or its antigen-binding fragment to which it is bound. Many of these markers are readily apparent to those skilled in the art, and for example, the detection marker may be selected from radioactive markers (e.g., radioisotopes), fluorescent markers (e.g., fluorescein, phenanthidine dyes), chemiluminescent markers (e.g., acridinium ester compounds, cyanine dyes, luminol, isoluminol), biotin, colloidal gold, electrochemiluminescent markers (e.g., tripyridineruthenium), quantum dots (e.g., gold quantum dots, CdSe quantum dots, ZnCdSe quantum dots), or enzymes (e.g., horseradish peroxidase, alkaline phosphatase, β-galactosidase).

[0055] As used herein, the term “double antibody sandwich method” specifically refers to the double antibody sandwich assay of enzyme-linked immunosorbent assay (ELISA), a commonly used immunoassay technique in which an antigen binds to two different antibodies, each binding to a different, non-overlapping, and non-interfering epitope on the antigen. In this assay, a sandwich complex is formed comprising a capture antibody, an antigen, and a detection antibody, with the antigen crosslinking the two antibodies to which it binds. In some embodiments, the present invention provides antibody pairs, i.e., combinations of a capture antibody and a detection antibody, which can be further used to prepare kits for detecting human immunodeficiency virus antigens.

[0056] The antibodies or antigen-binding fragments described in this invention can be used in a variety of assays for detecting human immunodeficiency virus antigens (e.g., HIV-1 p24 protein, HIV-2 p26 protein) in a sample. Some suitable assays include, but are not limited to, Western blotting, radioimmunoassay, immunofluorescence assay, immunoprecipitation, equilibrium dialysis, immunodiffusion, electrochemiluminescence (ECL) immunoassay, immunohistochemistry, fluorescence-activated cell sorting (FACS), or ELISA assays.

[0057] The present invention will be described in detail below in combination with specific embodiments and examples, thereby more clearly demonstrating the advantages and various effects of the present invention. As those skilled in the art will understand, these specific embodiments and examples are for illustrative purposes only and do not limit the present invention. In this specification, the same name refers to the same antibody or hybridoma cells expressing it, "rec" identifies recombinant antibodies, and when the names of two antibodies are distinguished only by the presence or absence of the "rec" identifier, the heavy chain variable region sequences and light chain variable region sequences of both are the same. [Examples]

[0058] Example 1 A mixture of three proteins was used as an antigen: the p24 protein from the M group of HIV-1 (abbreviated as p24_M), the p24 protein from the O group of HIV-1 (abbreviated as p24_O), and the p26 protein from HIV-2 (abbreviated as p26). The sequences of these three proteins can be found in the HIV Molecular Immunology Database at Los Alamos National Laboratory, with their respective sequence numbers being AB034308 for p24_M, AF383263 for p24_O, and AF025343 for p26. These proteins were obtained by recombinant expression and further purification in E. coli.

[0059] The above antigens were used to immunize mice, rats, and rabbits, respectively. By screening the hybridoma cells obtained through immunization, hybridoma cells expressing anti-p24 and p26 antibodies were acquired. The antibodies expressed by these cells were able to simultaneously and specifically bind to p24 protein (HIV-1 M and O groups) and p26 protein (HIV-2). RNA was extracted from the hybridoma cells obtained through screening, and the antibodies they produced were sequenced. Some of the sequencing results are shown in Tables 1, 2, and 3.

[0060] [Table 1]

[0061] [Table 2]

[0062] [Table 3]

[0063] Example 2 Antibodies were prepared according to the following methods.

[0064] 1. Monoclonal antibodies p24_113, p24_138: The hybridoma cells p24_113 and p24_138 obtained in Example 1 were injected into the peritoneal cavity of mice, respectively. Monoclonal antibodies p24_113 and p24_138 were prepared by inducing monoclonal antibody production in the mouse's ascites fluid and then purifying the antibodies.

[0065] 2. Recombinant antibodies p24_rec_131, p24_rec_140, p24_rec_151, p24_rec_179, p24_rec_252: Based on the sequencing results of the antibodies, the heavy chain variable region sequences and light chain variable region sequences of the antibodies expressed by the hybridoma cells p24_131, p24_140, p24_151, and p24_179 obtained in Example 1 were acquired. The heavy chain variable region sequences obtained by sequencing were fused with the isomorphic heavy chain constant region of rabbit immunoglobulin IgG to obtain the heavy chain sequence of the recombinant antibody. The light chain variable region sequences obtained by sequencing were fused with the isomorphic light chain constant region of rabbit immunoglobulin IgG to obtain the light chain sequence of the recombinant antibody. Thus, the heavy chain sequence and light chain sequence of the recombinant antibody were obtained, and expression vectors expressing them were constructed. Expression and purification were then performed using the mammalian cell line Expi293F.

[0066] Based on the antibody sequencing results, the heavy chain variable region sequence and light chain variable region sequence of the antibody expressed by the hybridoma cells p24_252 obtained in Example 1 were acquired. The heavy chain variable region sequence obtained by sequencing was fused with the isomorphic heavy chain constant region of sheep immunoglobulin IgG to obtain the heavy chain sequence of the recombinant antibody. The light chain variable region sequence obtained by sequencing was fused with the isomorphic light chain constant region of sheep immunoglobulin IgG to obtain the light chain sequence of the recombinant antibody. Thus, the heavy chain sequence and light chain sequence of the recombinant antibody were obtained, and expression vectors expressing them were constructed. Expression and purification were then performed using the mammalian cell line Expi293F.

[0067] Size exclusion chromatography (SEC) analysis was performed on the antibodies prepared as described above, and the results are shown in Figures 1 to 7, indicating that the prepared antibodies had good purity.

[0068] The relevant deposit information is as follows: All of the following biological materials have been deposited with the Russian State Industrial Microbiological Collection Center (VKPM) on September 17, 2024.

[0069] Accession number VKPM H-227 is the hybridoma cell line named p24_138, and is used to produce the monoclonal antibody p24_138.

[0070] Accession number VKPM H-228 is the hybridoma cell line named p24_113, and is used to produce the monoclonal antibody p24_113.

[0071] The Escherichia coli strain with accession number VKPM B-15024 is named Escherichia coli Rosetta™(DE3) pLysS p24_rec_131 VH and is used to produce a plasmid encoding the p24_rec_131 heavy chain sequence.

[0072] The Escherichia coli strain with accession number VKPM B-15025 is named Escherichia coli Rosetta™(DE3) pLysS p24_rec_131 VL and is used for the production of plasmids encoding the p24_rec_131 light chain sequence.

[0073] The Escherichia coli strain with accession number VKPM B-15026 is named Escherichia coli Rosetta™(DE3) pLysS p24_rec_140 VH and is used for the production of plasmids encoding the p24_rec_140 heavy chain sequence.

[0074] The Escherichia coli strain with accession number VKPM B-15027 is named Escherichia coli Rosetta™(DE3) pLysS p24_rec_140 VL and is used for the production of plasmids encoding the p24_rec_140 light chain sequence.

[0075] The Escherichia coli strain with accession number VKPM B-15028 is named Escherichia coli Rosetta™(DE3) pLysS p24_rec_151 VH and is used to produce a plasmid encoding the p24_rec_151 heavy chain sequence.

[0076] The Escherichia coli strain with accession number VKPM B-15029 is named Escherichia coli Rosetta™(DE3) pLysS p24_rec_151 VL and is used for the production of a plasmid encoding the p24_rec_151 light chain sequence.

[0077] The Escherichia coli bacterium with accession number VKPM B-15030 is named Escherichia coli Rosetta™(DE3) pLysS p24_rec_179 VH and is used for the production of plasmids encoding the p24_rec_179 heavy chain sequence.

[0078] The Escherichia coli strain with accession number VKPM B-15031 is named Escherichia coli Rosetta™(DE3) pLysS p24_rec_179 VL and is used for the production of plasmids encoding the p24_rec_179 light chain sequence.

[0079] The Escherichia coli strain with accession number VKPM B-15032 is named Escherichia coli Rosetta™(DE3) pLysS p24_rec_252 VH and is used for the production of plasmids encoding the p24_rec_252 heavy chain sequence.

[0080] The Escherichia coli strain with accession number VKPM B-15033 is named Escherichia coli Rosetta™(DE3) pLysS p24_rec_252 VL and is used for the production of plasmids encoding the p24_rec_252 light chain sequence.

[0081] Example 3 In this example, the affinity between the antibody and the HIV-1 M group p24 protein was measured. The procedure is as follows.

[0082] The antibody prepared in Example 2 was biotin-labeled to obtain a biotinylated antibody. The biotinylated antibody was added to a buffer (50 mM Tris-HCl buffer, pH 7.5, 150 mM NaCl, 0.01% Tween 40, 0.5% BSA, and 0.05% NaN3) to prepare an antibody solution for measurement, with a final concentration of 10 μg / ml of biotinylated antibody. The antibody solution for measurement was added to a streptavidin biosensor (FORTEBIO SA (streptavidin) Dip and Read biosensors) and held for 10 minutes. Then, it was washed with the above buffer for 10 minutes, and then p24 protein solutions at concentrations of 20 nM, 10 nM, and 5 nM were added, respectively, and incubated for 20 minutes. After that, dissociation was performed for 30 minutes, and the test results of the sensor were read. The results are shown in Table 4.

[0083] [Table 4]

[0084] As can be seen from Table 4, the antibodies mentioned above have good affinity for the p24 protein.

[0085] Example 4 When performing immunoassay using the dual antibody sandwich method, it is necessary to use two antibodies (or antibody pairs) simultaneously, one as a capture antibody and the other as a detection antibody. In this example, two antibodies prepared in Example 2 were combined, and antibody pairs suitable for the dual antibody sandwich method for detecting HIV-1 and HIV-2 were screened from among them. The procedure is as follows.

[0086] Preparation of capture antibody reagent: The capture antibody was labeled with biotin, and the biotin-labeled capture antibody was incubated with streptavidin-labeled magnetic beads (Dynabeads® MyOne® Streptavidin T1) to obtain magnetic beads conjugated with the capture antibody. These were added to buffer A (50 mM Tris-HCl, pH 7.4, 150 mM NaCl, 2% BSA, 0.2% Tween-20, 0.05% ProClin 300, 0.09% NaN3) to a final concentration of 0.2 mg / ml to prepare the capture antibody reagent.

[0087] Detection antibody reagent: The detection antibody was labeled with alkaline phosphatase, and then added to buffer B (50 mM MES, pH 6, 0.9% NaCl, 1% BSA, 0.05% Tween-20, 0.048% ProClin 300, 2 mM MgCl2, 0.1 mM ZnCl2) to a final concentration of 0.5 μg / ml to prepare the detection antibody reagent.

[0088] Test antigens were prepared by serially diluting the following antigens with buffer B: the World Health Organization (WHO) international standard HIV-1 p24 antigen (purchased from NIBSC, catalog number: 90 / 636), the HIV-1 M group p24 protein from Example 1 (abbreviated as p24_M in Table 5), the HIV-1 O group p24 protein (abbreviated as p24_O in Table 5), and the HIV-2 p26 protein (abbreviated as p26 in Table 5).

[0089] Immunodetection step: Detection was performed using a Mindray CL-6000i fully automated chemiluminescence immunoassay analyzer, following the instructions in the user manual, and using the substrate solution provided with the instrument. Chemiluminescence was expressed in relative luminescence units (RLU).

[0090] The test antigen was detected using the method described above, and the limit of detection was determined. A positive control was also established using a commercially available kit from Abbott. The following is a description of the detection of the limit of detection (LOD): For each test antigen sample, at least five serial dilution concentrations were established near the LOD, and 20 repeated measurements were performed at each concentration value for each test antigen sample. The LOD was calculated according to the CLSI (Clinical Laboratory Standards Institute) EP17-A document, with a β error risk of 0.05.

[0091] Table 5 shows some of the antibody pairs obtained through screening and their LODs.

[0092] [Table 5]

[0093] The antibody pair combination described above can simultaneously detect the p24 proteins of HIV-1 (groups O and M) and the p26 protein of HIV-2. Validation has confirmed that it can detect the WHO international standard HIV-1 p24 antigen. Furthermore, the detection limits for the above antigens of the antibody pair are superior to those of the commercially available Abbott HIV Ag / Ab combo kit.

[0094] The above describes only preferred embodiments of the present invention, and the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that are readily conceivable to those skilled in the art within the technical scope disclosed herein should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. An antibody or its antigen-binding fragment, The antibody or its antigen-binding fragment specifically binds to the p24 protein of human immunodeficiency virus type 1 and the p26 protein of human immunodeficiency virus type 2, and the antibody or its antigen-binding fragment comprises a heavy chain variable region containing the amino acid sequences of HCDR1, HCDR2, and HCDR3, and a light chain variable region containing the amino acid sequences of LCDR1, LCDR2, and LCDR3. The amino acid sequence of HCDR1 is selected from SEQ ID NO: 1, 7, 13, 19, 25, 31, 37 or its variants; the amino acid sequence of HCDR2 is selected from SEQ ID NO: 2, 8, 14, 20, 26, 32, 38 or its variants; the amino acid sequence of HCDR3 is selected from SEQ ID NO: 3, 9, 15, 21, 27, 33, 39 or its variants. The amino acid sequence of LCDR1 is selected from SEQ ID NO: 4, 10, 16, 22, 28, 34, 40 or its variants; the amino acid sequence of LCDR2 is selected from SEQ ID NO: 5, 11, 17, 23, 29, 35, 41 or its variants; the amino acid sequence of LCDR3 is selected from SEQ ID NO: 6, 12, 18, 24, 30, 36, 42 or its variants. The variant includes amino acid mutations compared to the amino acid sequence from which it is derived, the amino acid mutations being substitutions, deletions or additions of one or more amino acids, and the variant has at least 80%, at least 85%, at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, or at least 99% identity with the amino acid sequence from which it is derived. An antibody or its antigen-binding fragment.

2. In the antibody or its antigen-binding fragment, The amino acid sequence of HCDR1 is SEQ ID NO: 1, the amino acid sequence of HCDR2 is SEQ ID NO: 2, the amino acid sequence of HCDR3 is SEQ ID NO: 3, the amino acid sequence of LCDR1 is SEQ ID NO: 4, the amino acid sequence of LCDR2 is SEQ ID NO: 5, the amino acid sequence of LCDR3 is SEQ ID NO: 6, or The amino acid sequence of HCDR1 is SEQ ID NO: 7, the amino acid sequence of HCDR2 is SEQ ID NO: 8, the amino acid sequence of HCDR3 is SEQ ID NO: 9, the amino acid sequence of LCDR1 is SEQ ID NO: 10, the amino acid sequence of LCDR2 is SEQ ID NO: 11, the amino acid sequence of LCDR3 is SEQ ID NO: 12, or The amino acid sequence of HCDR1 is SEQ ID NO: 13, the amino acid sequence of HCDR2 is SEQ ID NO: 14, the amino acid sequence of HCDR3 is SEQ ID NO: 15, the amino acid sequence of LCDR1 is SEQ ID NO: 16, the amino acid sequence of LCDR2 is SEQ ID NO: 17, the amino acid sequence of LCDR3 is SEQ ID NO: 18, or The amino acid sequence of HCDR1 is SEQ ID NO: 19, the amino acid sequence of HCDR2 is SEQ ID NO: 20, the amino acid sequence of HCDR3 is SEQ ID NO: 21, the amino acid sequence of LCDR1 is SEQ ID NO: 22, the amino acid sequence of LCDR2 is SEQ ID NO: 23, the amino acid sequence of LCDR3 is SEQ ID NO: 24, or The amino acid sequence of HCDR1 is SEQ ID NO: 25, the amino acid sequence of HCDR2 is SEQ ID NO: 26, the amino acid sequence of HCDR3 is SEQ ID NO: 27, the amino acid sequence of LCDR1 is SEQ ID NO: 28, the amino acid sequence of LCDR2 is SEQ ID NO: 29, the amino acid sequence of LCDR3 is SEQ ID NO: 30, or The amino acid sequence of HCDR1 is SEQ ID NO: 31, the amino acid sequence of HCDR2 is SEQ ID NO: 32, the amino acid sequence of HCDR3 is SEQ ID NO: 33, the amino acid sequence of LCDR1 is SEQ ID NO: 34, the amino acid sequence of LCDR2 is SEQ ID NO: 35, the amino acid sequence of LCDR3 is SEQ ID NO: 36, or The amino acid sequence of HCDR1 is SEQ ID NO: 37, the amino acid sequence of HCDR2 is SEQ ID NO: 38, the amino acid sequence of HCDR3 is SEQ ID NO: 39, the amino acid sequence of LCDR1 is SEQ ID NO: 40, the amino acid sequence of LCDR2 is SEQ ID NO: 41, and the amino acid sequence of LCDR3 is SEQ ID NO:

42. The antibody or antigen-binding fragment thereof according to claim 1.

3. The antibody is a full-length antibody, a Fab fragment, a Fab' fragment, an F(ab')2 fragment, a double-stranded Fv fragment, or a single-stranded Fv fragment, or The type of the antibody or its antigen-binding fragment is IgG, IgM, IgE, IgD, or IgA, or The antibody or its antigen-binding fragment is a mouse-derived antibody, a rabbit-derived antibody, or a humanized antibody. The antibody or antigen-binding fragment thereof according to claim 1.

4. The antibody comprises a constant region, and the constant region comprises a heavy chain constant region and / or a light chain constant region, or The antibody includes a constant region, and the constant region includes a mouse constant region, a rat constant region, a rabbit constant region, a sheep constant region, a monkey constant region, or a human constant region, or The antibody comprises a constant region, the constant region comprises a heavy chain constant region and / or a light chain constant region, the heavy chain constant region is the heavy chain constant region of IgG1, IgG2, IgG3, or IgG4, or the light chain constant region is a κ or λ type light chain constant region. The antibody or antigen-binding fragment thereof according to claim 1.

5. The antibody or its antigen-binding fragment is further bound to a detection marker, the detection marker comprising at least one selected from the group consisting of a radioactive marker, a fluorescent marker, a chemiluminescent marker, biotin, colloidal gold, an electrochemiluminescent marker, a quantum dot, or an enzyme. An antibody or antigen-binding fragment thereof according to any one of claims 1 to 4.

6. An antibody or its antigen-binding fragment comprising at least one selected from the following group: Antibodies or antigen-binding fragments thereof produced by the hybridoma cell line with accession number VKPM H-227, deposited with VKPM; Antibodies or antigen-binding fragments thereof produced by the hybridoma cell line with accession number VKPM H-228, deposited with VKPM; Antibodies or antigen-binding fragments thereof produced by plasmids in Escherichia coli with accession number VKPM B-15024 and plasmids in Escherichia coli with accession number VKPM B-15025, deposited with VKPM; Antibodies or antigen-binding fragments thereof produced by plasmids in E. coli with accession number VKPM B-15026 and plasmids in E. coli with accession number VKPM B-15027, deposited with VKPM; Antibodies or antigen-binding fragments thereof produced by plasmids in Escherichia coli with accession number VKPM B-15028 and plasmids in Escherichia coli with accession number VKPM B-15029, deposited with VKPM; Antibodies or antigen-binding fragments thereof produced by plasmids in E. coli with accession number VKPM B-15030 and plasmids in E. coli with accession number VKPM B-15031, deposited with VKPM; and Antibodies or antigen-binding fragments thereof produced by plasmids in E. coli with accession number VKPM B-15032 and plasmids in E. coli with accession number VKPM B-15033, deposited with VKPM.

7. Encoding an antibody or antigen-binding fragment thereof according to any one of claims 1 to 4, 6, Isolated polynucleotides.

8. A polynucleotide comprising the isolated polynucleotide described in claim 7, vector.

9. The isolated polynucleotide described in claim 7, or the vector described in claim 8, host cell.

10. The antibody comprises a capture antibody and a detection antibody, wherein at least one of the capture antibody and the detection antibody is selected from the antibody or antigen-binding fragment thereof described in any one of claims 1 to 4, 6. Antibody pair.

11. The capture antibody and the detection antibody are each independently selected from the antibodies or antigen-binding fragments described in any one of claims 1 to 4, 6, and the capture antibody and the detection antibody are not the same. The antibody pair is selected from any of the following groups (i) to (vi), namely, (i) A capture antibody comprising HCDR1 having amino acid sequence SEQ ID NO:1, HCDR2 having amino acid sequence SEQ ID NO:2, HCDR3 having amino acid sequence SEQ ID NO:3, LCDR1 having amino acid sequence SEQ ID NO:4, LCDR2 having amino acid sequence SEQ ID NO:5, and LCDR3 having amino acid sequence SEQ ID NO:6, and A detection antibody selected from one of the following groups: Detection antibody containing HCDR1 with amino acid sequence SEQ ID NO: 13, HCDR2 with amino acid sequence SEQ ID NO: 14, HCDR3 with amino acid sequence SEQ ID NO: 15, LCDR1 with amino acid sequence SEQ ID NO: 16, LCDR2 with amino acid sequence SEQ ID NO: 17, and LCDR3 with amino acid sequence SEQ ID NO: 18; A detection antibody comprising HCDR1 with amino acid sequence SEQ ID NO: 19, HCDR2 with amino acid sequence SEQ ID NO: 20, HCDR3 with amino acid sequence SEQ ID NO: 21, LCDR1 with amino acid sequence SEQ ID NO: 22, LCDR2 with amino acid sequence SEQ ID NO: 23, and LCDR3 with amino acid sequence SEQ ID NO: 24; or, Detection antibody containing HCDR1 with amino acid sequence SEQ ID NO: 25, HCDR2 with amino acid sequence SEQ ID NO: 26, HCDR3 with amino acid sequence SEQ ID NO: 27, LCDR1 with amino acid sequence SEQ ID NO: 28, LCDR2 with amino acid sequence SEQ ID NO: 29, and LCDR3 with amino acid sequence SEQ ID NO: 30; (ii) A capture antibody comprising HCDR1 having amino acid sequence SEQ ID NO: 7, HCDR2 having amino acid sequence SEQ ID NO: 8, HCDR3 having amino acid sequence SEQ ID NO: 9, LCDR1 having amino acid sequence SEQ ID NO: 10, LCDR2 having amino acid sequence SEQ ID NO: 11, and LCDR3 having amino acid sequence SEQ ID NO: 12, and A detection antibody selected from one of the following groups: A detection antibody containing HCDR1 (amino acid sequence SEQ ID NO: 1), HCDR2 (amino acid sequence SEQ ID NO: 2), HCDR3 (amino acid sequence SEQ ID NO: 3), LCDR1 (amino acid sequence SEQ ID NO: 4), LCDR2 (amino acid sequence SEQ ID NO: 5), and LCDR3 (amino acid sequence SEQ ID NO: 6); Detection antibody containing HCDR1 with amino acid sequence SEQ ID NO: 13, HCDR2 with amino acid sequence SEQ ID NO: 14, HCDR3 with amino acid sequence SEQ ID NO: 15, LCDR1 with amino acid sequence SEQ ID NO: 16, LCDR2 with amino acid sequence SEQ ID NO: 17, and LCDR3 with amino acid sequence SEQ ID NO: 18; Detection antibody containing HCDR1 with amino acid sequence SEQ ID NO: 19, HCDR2 with amino acid sequence SEQ ID NO: 20, HCDR3 with amino acid sequence SEQ ID NO: 21, LCDR1 with amino acid sequence SEQ ID NO: 22, LCDR2 with amino acid sequence SEQ ID NO: 23, and LCDR3 with amino acid sequence SEQ ID NO: 24; Detection antibody containing HCDR1 with amino acid sequence SEQ ID NO: 25, HCDR2 with amino acid sequence SEQ ID NO: 26, HCDR3 with amino acid sequence SEQ ID NO: 27, LCDR1 with amino acid sequence SEQ ID NO: 28, LCDR2 with amino acid sequence SEQ ID NO: 29, and LCDR3 with amino acid sequence SEQ ID NO: 30; A detection antibody comprising HCDR1 with amino acid sequence SEQ ID NO: 31, HCDR2 with amino acid sequence SEQ ID NO: 32, HCDR3 with amino acid sequence SEQ ID NO: 33, LCDR1 with amino acid sequence SEQ ID NO: 34, LCDR2 with amino acid sequence SEQ ID NO: 35, and LCDR3 with amino acid sequence SEQ ID NO: 36; or, A detection antibody containing HCDR1 with amino acid sequence SEQ ID NO: 37, HCDR2 with amino acid sequence SEQ ID NO: 38, HCDR3 with amino acid sequence SEQ ID NO: 39, LCDR1 with amino acid sequence SEQ ID NO: 40, LCDR2 with amino acid sequence SEQ ID NO: 41, and LCDR3 with amino acid sequence SEQ ID NO: 42; (iii) Capture antibodies comprising HCDR1 having amino acid sequence SEQ ID NO: 13, HCDR2 having amino acid sequence SEQ ID NO: 14, HCDR3 having amino acid sequence SEQ ID NO: 15, LCDR1 having amino acid sequence SEQ ID NO: 16, LCDR2 having amino acid sequence SEQ ID NO: 17, and LCDR3 having amino acid sequence SEQ ID NO: 18, and A detection antibody comprising HCDR1 with amino acid sequence SEQ ID NO: 37, HCDR2 with amino acid sequence SEQ ID NO: 38, HCDR3 with amino acid sequence SEQ ID NO: 39, LCDR1 with amino acid sequence SEQ ID NO: 40, LCDR2 with amino acid sequence SEQ ID NO: 41, and LCDR3 with amino acid sequence SEQ ID NO: 42; (iv) A capture antibody comprising HCDR1 with amino acid sequence SEQ ID NO: 19, HCDR2 with amino acid sequence SEQ ID NO: 20, HCDR3 with amino acid sequence SEQ ID NO: 21, LCDR1 with amino acid sequence SEQ ID NO: 22, LCDR2 with amino acid sequence SEQ ID NO: 23, and LCDR3 with amino acid sequence SEQ ID NO: 24, and A detection antibody comprising HCDR1 with amino acid sequence SEQ ID NO: 37, HCDR2 with amino acid sequence SEQ ID NO: 38, HCDR3 with amino acid sequence SEQ ID NO: 39, LCDR1 with amino acid sequence SEQ ID NO: 40, LCDR2 with amino acid sequence SEQ ID NO: 41, and LCDR3 with amino acid sequence SEQ ID NO: 42; (v) A capture antibody comprising HCDR1 having amino acid sequence SEQ ID NO: 25, HCDR2 having amino acid sequence SEQ ID NO: 26, HCDR3 having amino acid sequence SEQ ID NO: 27, LCDR1 having amino acid sequence SEQ ID NO: 28, LCDR2 having amino acid sequence SEQ ID NO: 29, and LCDR3 having amino acid sequence SEQ ID NO: 30, and A detection antibody selected from one of the following groups: Detection antibody containing HCDR1 with amino acid sequence SEQ ID NO: 13, HCDR2 with amino acid sequence SEQ ID NO: 14, HCDR3 with amino acid sequence SEQ ID NO: 15, LCDR1 with amino acid sequence SEQ ID NO: 16, LCDR2 with amino acid sequence SEQ ID NO: 17, and LCDR3 with amino acid sequence SEQ ID NO: 18; Detection antibody containing HCDR1 with amino acid sequence SEQ ID NO: 19, HCDR2 with amino acid sequence SEQ ID NO: 20, HCDR3 with amino acid sequence SEQ ID NO: 21, LCDR1 with amino acid sequence SEQ ID NO: 22, LCDR2 with amino acid sequence SEQ ID NO: 23, and LCDR3 with amino acid sequence SEQ ID NO: 24; A detection antibody comprising HCDR1 with amino acid sequence SEQ ID NO: 31, HCDR2 with amino acid sequence SEQ ID NO: 32, HCDR3 with amino acid sequence SEQ ID NO: 33, LCDR1 with amino acid sequence SEQ ID NO: 34, LCDR2 with amino acid sequence SEQ ID NO: 35, and LCDR3 with amino acid sequence SEQ ID NO: 36; or, A detection antibody containing HCDR1 with amino acid sequence SEQ ID NO: 37, HCDR2 with amino acid sequence SEQ ID NO: 38, HCDR3 with amino acid sequence SEQ ID NO: 39, LCDR1 with amino acid sequence SEQ ID NO: 40, LCDR2 with amino acid sequence SEQ ID NO: 41, and LCDR3 with amino acid sequence SEQ ID NO: 42; (vi) A capture antibody comprising HCDR1 having amino acid sequence SEQ ID NO: 31, HCDR2 having amino acid sequence SEQ ID NO: 32, HCDR3 having amino acid sequence SEQ ID NO: 33, LCDR1 having amino acid sequence SEQ ID NO: 34, LCDR2 having amino acid sequence SEQ ID NO: 35, and LCDR3 having amino acid sequence SEQ ID NO: 36, and A detection antibody selected from one of the following groups: A detection antibody comprising: HCDR1 with amino acid sequence SEQ ID NO:1, HCDR2 with amino acid sequence SEQ ID NO:2, HCDR3 with amino acid sequence SEQ ID NO:3, LCDR1 with amino acid sequence SEQ ID NO:4, LCDR2 with amino acid sequence SEQ ID NO:5, and LCDR3 with amino acid sequence SEQ ID NO:6; or, A detection antibody containing HCDR1 with amino acid sequence SEQ ID NO: 37, HCDR2 with amino acid sequence SEQ ID NO: 38, HCDR3 with amino acid sequence SEQ ID NO: 39, LCDR1 with amino acid sequence SEQ ID NO: 40, LCDR2 with amino acid sequence SEQ ID NO: 41, and LCDR3 with amino acid sequence SEQ ID NO: 42; The antibody pair according to claim 10.

12. The antibody pair is selected from any of the following groups (a) to (f): (a) A capture antibody produced by a hybridoma cell line with accession number VKPM H-228 deposited with VKPM, and A detection antibody selected from one of the following groups: Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15024 and plasmids in E. coli with accession number VKPM B-15025, deposited with VKPM; - Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15026 and plasmids in E. coli with accession number VKPM B-15027, deposited with VKPM; or, Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15028 and plasmids in E. coli with accession number VKPM B-15029, deposited with VKPM; (b) A capture antibody produced by a hybridoma cell line with accession number VKPM H-227 deposited with VKPM, and A detection antibody selected from one of the following groups: - Detection antibody produced by the hybridoma cell line with accession number VKPM H-228, deposited with VKPM; Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15024 and plasmids in E. coli with accession number VKPM B-15025, deposited with VKPM; Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15026 and plasmids in E. coli with accession number VKPM B-15027, deposited with VKPM; Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15028 and plasmids in E. coli with accession number VKPM B-15029, deposited with VKPM; - Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15030 and plasmids in E. coli with accession number VKPM B-15031, deposited with VKPM; or, Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15032 and plasmids in E. coli with accession number VKPM B-15033, deposited with VKPM; (c) Capture antibodies produced by plasmids in E. coli with accession number VKPM B-15024 and plasmids in E. coli with accession number VKPM B-15025, deposited with VKPM, A detection antibody produced by plasmids in E. coli with accession number VKPM B-15032 and plasmids in E. coli with accession number VKPM B-15033, deposited with VKPM. (d) Capture antibodies produced by plasmids in E. coli with accession number VKPM B-15026 and plasmids in E. coli with accession number VKPM B-15027, deposited with VKPM, A detection antibody produced by plasmids in E. coli with accession number VKPM B-15032 and plasmids in E. coli with accession number VKPM B-15033, deposited with VKPM. (e) Capture antibodies produced by plasmids in E. coli with accession number VKPM B-15028 and plasmids in E. coli with accession number VKPM B-15029, deposited with VKPM, A detection antibody selected from one of the following groups: Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15024 and plasmids in E. coli with accession number VKPM B-15025, deposited with VKPM; Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15026 and plasmids in E. coli with accession number VKPM B-15027, deposited with VKPM; - Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15030 and plasmids in E. coli with accession number VKPM B-15031, deposited with VKPM; or, Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15032 and plasmids in E. coli with accession number VKPM B-15033, deposited with VKPM; (f) Capture antibodies produced by plasmids in E. coli with accession number VKPM B-15030 and plasmids in E. coli with accession number VKPM B-15031, deposited with VKPM, A detection antibody selected from one of the following groups: - Detection antibody produced by the hybridoma cell line with accession number VKPM H-228 deposited with VKPM; or, Detection antibodies produced by plasmids in E. coli with accession number VKPM B-15032 and plasmids in E. coli with accession number VKPM B-15033, deposited with VKPM; The antibody pair according to claim 10.

13. A kit comprising an antibody or antigen-binding fragment thereof according to any one of claims 1 to 4, 6, or an antibody pair according to any one of claims 10 to 12.

14. A method for detecting human immunodeficiency virus, A method for detecting human immunodeficiency virus, comprising performing detection on a sample using an antibody or antigen-binding fragment thereof according to any one of claims 1 to 4, 6, or an antibody pair according to any one of claims 10 to 12.

15. The aforementioned human immunodeficiency virus includes human immunodeficiency virus type 1 and human immunodeficiency virus type 2. The application described in claim 14.

16. A method to assist in the diagnosis of acquired immunodeficiency syndrome and AIDS-related syndromes, A method for assisting the diagnosis of acquired immunodeficiency syndrome and AIDS-related syndromes, comprising performing detection on a sample using an antibody or antigen-binding fragment thereof according to any one of claims 1 to 4, 6, or an antibody pair according to any one of claims 10 to 12.

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