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CN-121991235-A - Antibody for detecting total antibody concentration in blood, kit and application thereof

CN121991235ACN 121991235 ACN121991235 ACN 121991235ACN-121991235-A

Abstract

The invention relates to an antibody for detecting total antibody concentration in blood, and a kit and application thereof, wherein the antibody comprises (1) a first antibody comprising a heavy chain variable region VH1 and a light chain variable region VL1, wherein VH1 comprises three CDRs S in a sequence shown as SEQ ID NO:41, VL1 comprises three CDRs S in a sequence shown as SEQ ID NO:42, and/or (2) a second antibody comprising a heavy chain variable region VH2 and a light chain variable region VL2, wherein VH2 comprises three CDRs S in a sequence shown as SEQ ID NO:43, and VL2 comprises three CDRs S in a sequence shown as SEQ ID NO: 44. The antibody provided by the invention has the advantages of excellent sensitivity, accuracy and stability, strong anti-target interference capability and the like when used for detecting the total antibody concentration in blood.

Inventors

  • SHI QIFENG

Assignees

  • 苏州信诺维医药科技股份有限公司

Dates

Publication Date
20260508
Application Date
20260331

Claims (12)

  1. 1. An antibody for use in detecting total antibody concentration in blood, the antibody comprising: (1) A first antibody comprising a heavy chain variable region VH1 and a light chain variable region VL1, wherein the VH1 comprises HCDR1, HCDR2, HCDR3 in the amino acid sequence shown as SEQ ID NO: 41, the VL1 comprises LCDR1, LCDR2, LCDR3 in the amino acid sequence shown as SEQ ID NO: 42, and/or, (2) A second antibody comprising a heavy chain variable region VH2 and a light chain variable region VL2, wherein the VH2 comprises HCDR1, HCDR2 and HCDR3 in the amino acid sequence shown as SEQ ID NO. 43, and the VL2 comprises LCDR1, LCDR2 and LCDR3 in the amino acid sequence shown as SEQ ID NO. 44.
  2. 2. The antibody of claim 1, wherein the complementarity determining regions of the antibody are defined based on the IMGT antibody encoding system, wherein, The first antibody has HCDR1 shown as SEQ ID NO. 1, HCDR2 shown as SEQ ID NO.2, HCDR3 shown as SEQ ID NO. 3, LCDR1 shown as SEQ ID NO. 4, LCDR2 with amino acid sequence LTS, LCDR3 shown as SEQ ID NO. 6, and/or, The second antibody has HCDR1 shown as SEQ ID NO. 9, HCDR2 shown as SEQ ID NO. 10, HCDR3 shown as SEQ ID NO. 11, LCDR1 shown as SEQ ID NO. 12, LCDR2 with NAK amino acid sequence and LCDR3 shown as SEQ ID NO. 14.
  3. 3. The antibody of claim 1 or 2, wherein the VH1 comprises an amino acid sequence having at least 80% identity to the amino acid sequence shown in SEQ ID NO. 41 and/or the VL1 comprises an amino acid sequence having at least 80% identity to the amino acid sequence shown in SEQ ID NO. 42; And/or the VH2 comprises an amino acid sequence having at least 80% identity to the amino acid sequence shown in SEQ ID NO. 43 and/or the VL2 comprises an amino acid sequence having at least 80% identity to the amino acid sequence shown in SEQ ID NO. 44.
  4. 4. The antibody of claim 3, wherein the VH1 comprises or consists of the amino acid sequence shown as SEQ ID NO. 41 and/or the VL1 comprises or consists of the amino acid sequence shown as SEQ ID NO. 42 or consists of SEQ ID NO. 42; And/or the VH2 comprises or consists of the amino acid sequence shown as SEQ ID NO. 43, and/or the VL2 comprises or consists of the amino acid sequence shown as SEQ ID NO. 44, or consists of SEQ ID NO. 44.
  5. 5. The antibody of claim 1, wherein the antibody is a full length antibody comprising a heavy chain and a light chain, and the heavy chain and light chain amino acid sequences of the first antibody and/or the second antibody comprise: (1) The heavy chain of the first antibody comprises an amino acid sequence having at least 80% identity to the amino acid sequence shown in SEQ ID NO. 7, the light chain comprises an amino acid sequence having at least 80% identity to the amino acid sequence shown in SEQ ID NO. 8, and/or, (2) The heavy chain of the second antibody comprises an amino acid sequence having at least 80% identity to the amino acid sequence set forth in SEQ ID NO. 15, and the light chain comprises an amino acid sequence having at least 80% identity to the amino acid sequence set forth in SEQ ID NO. 16.
  6. 6. The antibody according to claim 5, wherein the heavy chain of the first antibody has an amino acid sequence shown in SEQ ID NO. 7 and the light chain has an amino acid sequence shown in ID NO. 8 and/or, The amino acid sequence of the heavy chain of the second antibody is shown as SEQ ID NO. 15, and the amino acid sequence of the light chain is shown as ID NO. 16.
  7. 7. An isolated polynucleotide encoding the antibody of any one of claims 1-6.
  8. 8. A carrier, characterized in that, the vector comprises the polynucleotide of claim 7.
  9. 9. A host cell comprising the polynucleotide of claim 7 or the vector of claim 8.
  10. 10. A kit comprising the antibody of any one of claims 1-6.
  11. 11. The kit according to claim 10, wherein the kit comprises a coated antibody and a detection antibody, the coated antibody is a first antibody and the detection antibody is a second antibody, the detection antibody is labeled with a detectable label, and the detectable label is selected from one or more of biotin, fluorescein, and an enzyme; And/or the kit further comprises one or more of HRP-labeled streptavidin, coating buffer, cleaning solution, analysis buffer, blocking solution, chromogenic solution, stop solution or complex solution of antibody drug conjugate or standard substance.
  12. 12. Use of an antibody according to any one of claims 1 to 6, or a kit according to claim 10 or 11, for the preparation of a product for detecting total antibody concentration in blood.

Description

Antibody for detecting total antibody concentration in blood, kit and application thereof Technical Field The invention relates to the field of antibody medical detection. In particular to an antibody for detecting the concentration of total antibodies in blood, a kit and application thereof. Background Tissue Factor (TF) is also known as thromboplastin (thromboplastin), CD142, or Factor 3. As a transmembrane glycoprotein, TF consists of an extracellular domain, a transmembrane region and an intracellular domain. TF is an essential molecule for initiation of an extrinsic coagulation event and is expressed in functional form on the cell surface. Under normal physiological conditions, TF is located on adventitial cells of the vessel wall and fibroblasts surrounding the vessel, but the intima or intima layer is rare in the vessel. TF is exposed to circulating blood only when the integrity of the vessel wall is compromised, exerting a hemostatic effect by activating the coagulation cascade. In contrast to limited expression on normal tissues and cells, TF has been demonstrated to be overexpressed on a variety of malignancies, including cervical cancer, pancreatic cancer, lung cancer, prostate cancer, bladder cancer, ovarian cancer, breast cancer, colorectal cancer, and the like. Therefore, TF can be used as a target for development of antibody drugs and ADC (antibody-drug conjugate) drugs. There are a number of TF-targeting ADC drugs (e.g. disclosed in WO2023/160651 et al). Along with the wide clinical application of TF-ADC drugs, the relevant monitoring in the treatment is very important, and the antibody drugs can induce the generation of drug-resistant antibodies (ADA), the ADA can be combined with therapeutic antibodies to neutralize the biological activity or accelerate the clearance of the therapeutic antibodies, so that the curative effect is reduced, and allergic reactions such as immune complex deposition and the like can be possibly caused in severe cases, so that the safety risk is brought. For this reason, both domestic and foreign drug regulatory authorities require that biological agents must be evaluated for immunogenicity in clinical development and post-market research, i.e., detection of ADA in the serum of a subject. Pharmacokinetic (PK) studies are advantageous for drug safety and effective assessment, but for ADC drugs, ADC heterogeneity is high and multiple test substances must be assessed to determine their Pharmacokinetic (PK) profile. Total antibodies (Total antibodies), including whole ADC, free naked antibodies (no load), antibodies in ADC-anti-drug Antibody (ADA) complexes, are capable of reflecting the Total exposure of ADC drugs in vivo, levels often used to characterize ADC drug PK. Too low a concentration of total antibodies may result in insufficient efficacy and too high a concentration may increase the risk of immunogenicity Currently, analytical methods in biological samples include immunoassay methods, which mostly employ enzyme-linked immunosorbent assay (ELISA) or electrochemical luminescence (ECL), but these methods often face problems of matrix interference, insufficient sensitivity, and poor capture ability for low affinity antibodies. The Elisa double-antibody sandwich method is to combine the coating antibody onto ELISA plate, then add the antibody to be detected to combine with the coating antibody, then add the specific secondary antibody, finally add the enzyme-labeled detection antibody and utilize the substrate to catalyze the color reaction. In this way, the antibody to be detected is specifically combined with the coated antibodies and the second antibodies of different binding epitopes, and the streptavidin marked by horseradish peroxidase is combined with the second antibody marked by biotin, so that the multistage amplification effect is achieved, and the kit has the advantages of high specificity, high sensitivity, stability and the like. With the progress of further clinical work on TF-ADC drugs, there is an urgent need to be able to accurately and reliably detect the total antibody concentration of ADC drugs in human serum, accurately capture the drug release profile, to aid in making effective therapeutic decisions and monitoring the progress of therapy. Disclosure of Invention In order to meet the above-mentioned needs, the present invention provides an antibody for detecting the concentration of total antibodies in blood, and a kit and use comprising the same. As shown in the examples, the antibodies of the invention have high specificity, high sensitivity and high stability properties. The antibody and the Elisa detection method can effectively detect the total antibody concentration of the TF-ADC drugs in blood, thereby being applied to detecting the total antibody concentration of the ADC drugs in blood after drug administration, accurately capturing the drug release dynamics and helping to monitor the treatment effect and the treatment progress. So