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CN-121991218-A - Antibody for detecting beta-amyloid and application thereof

CN121991218ACN 121991218 ACN121991218 ACN 121991218ACN-121991218-A

Abstract

The invention discloses an antibody for detecting beta-amyloid and application thereof, in particular relates to a detection antibody and a kit for detecting Alzheimer's disease blood markers Abeta 1-40 and Abeta 1-42, wherein the kit comprises three antibodies aiming at different antigenic determinants of beta-amyloid, and the existence of the beta-amyloid can be accurately detected based on the antibodies and the kit.

Inventors

  • GUO WEIYUN
  • YAN PANPAN
  • ZHANG SHUANG

Assignees

  • 东莞市朋志生物科技有限公司

Dates

Publication Date
20260508
Application Date
20241106

Claims (10)

  1. 1. An antibody for detecting beta-amyloid, characterized in that, The antibody comprises three heavy chain complementarity determining regions of HCDR1, HCDR2 and HCDR3 in the heavy chain variable region shown in any one of SEQ ID NO. 19, 20, 21, 22, 45 and 65 and three light chain complementarity determining regions of LCDR1, LCDR2 and LCDR3 in the light chain variable region shown in any one of SEQ ID NO. 27, 47 and 67; Optionally, the HCDR1, HCDR2, HCDR3, LCDR1, LCDR2, LCDR3 is defined by any one or a combination of systems Kabat, chothia, IMGT, abM or contacts.
  2. 2. An antibody for detecting β -amyloid, wherein the complementarity determining region of the antibody comprises any one of (a ')to (c'): (a') an amino acid sequence of HCDR1 shown in SEQ ID NO. 1 (AYYIH), HCDR2 shown in SEQ ID NO. 2 (RIDPATGNTKYAPRLQD) or 15 (RLDPATGNTKYAPRLQD), HCDR3 shown in SEQ ID NO. 3 (LYSLPVY) or 16 (IYSLPVY), and an amino acid sequence of LCDR1 shown in SEQ ID NO. 4 (KSSQSLLYSDAKTYLN), LCDR2 shown in SEQ ID NO. 5 (QISRLDP), LCDR3 shown in SEQ ID NO. 6 (LQGTHYPVL) in this order; (b') the amino acid sequence is shown as HCDR1 shown in SEQ ID NO 29 (NYGMS) and SEQ ID NO 30 in sequence (SIRSGGGRTYYSDNVKG) HCDR2 shown in SEQ ID NO:31 (YDHYSGSSDY), and LCDR1 shown in SEQ ID NO:32 (KSSQSLLDSDGKTYLN), LCDR2 shown in SEQ ID NO:33 (LVSKLDS), LCDR3 shown in SEQ ID NO:33 (WQGTHFPRT), and the amino acid sequence in that order (C') HCDR1, SEQ ID NO 50, the amino acid sequence of which is shown in SEQ ID NO 49 (DYTMH) in order (GINPNSGGTIYNEKFKD) HCDR2 shown in SEQ ID NO:51 (GVYDGYFY), and LCDR1 shown in SEQ ID NO:52 (RSSQSLVYSNGNTFLH), LCDR2 shown in SEQ ID NO:53 (KVSTRFSGVPDRFS), LCDR3 shown in SEQ ID NO:54 (SQTTHAPFT) in that order.
  3. 3. The antibody of claim 1 or 2, wherein the antibody further comprises a framework region of HFR1, HFR2, HFR3, HFR4, LFR1, LFR2, LFR3, and LFR 4; optionally, the HFR1, HFR2, HFR3, HFR4, LFR1, LFR2, LFR3, and LFR4 are selected from any one group of (a) - (c): (a) The amino acid sequences are shown as HFR1, HFR2, HFR3 and HFR4 shown in SEQ ID NO 7 to SEQ ID NO 10 in sequence, and LFR1, LFR2, LFR3 and LFR4 shown in SEQ ID NO 11 to SEQ ID NO 14 in sequence, or the amino acid sequences with at least 80% of the identity with the sequences of the framework regions; (b) HFR1, HFR2, HFR3, HFR4 having amino acid sequences shown in SEQ ID NO. 55 to SEQ ID NO. 58, and LFR1, LFR2, LFR3, LFR4 having amino acid sequences shown in SEQ ID NO. 59 to SEQ ID NO. 62, or an amino acid sequence having at least 80% identity to the respective framework region sequences, and (C) The amino acid sequences are shown as HFR1, HFR2, HFR3 and HFR4 shown in SEQ ID NO. 35 to SEQ ID NO. 38, and the amino acid sequences are shown as LFR1, LFR2, LFR3 and LFR4 shown in SEQ ID NO. 39 to SEQ ID NO. 42, or the amino acid sequences with at least 80% identity with the sequences of the framework regions.
  4. 4. An antibody for detecting beta-amyloid, which is characterized by comprising a heavy chain variable region and a light chain variable region, wherein the amino acid sequence of the heavy chain variable region is shown as any one of SEQ ID NO. 19, 20, 21, 22, 45 and 65, and the amino acid sequence of the light chain variable region is shown as any one of SEQ ID NO. 27, 47 and 67; Optionally, the amino acid sequences of the heavy chain variable region and the light chain variable region are selected from any one group of (A) to (C): (A) A heavy chain variable region with an amino acid sequence shown in any one of SEQ ID NO. 19, 20, 21 and 22, and a light chain variable region with an amino acid sequence shown in SEQ ID NO. 27; (B) A heavy chain variable region having an amino acid sequence shown as SEQ ID NO. 45, and a light chain variable region having an amino acid sequence shown as SEQ ID NO. 47, and (C) A heavy chain variable region having an amino acid sequence shown as SEQ ID NO. 65, and a light chain variable region having an amino acid sequence shown as SEQ ID NO. 67.
  5. 5. The antibody of any one of claims 1 to 4, further comprising a constant region; Alternatively, the constant region is of a species source of bovine, equine, porcine, ovine, caprine, rat, mouse, canine, camel, feline, rabbit, donkey, deer, mink, chicken, duck, goose, or human; alternatively, the constant region is of mouse species origin Optionally, the constant region comprises a heavy chain constant region and/or a light chain constant region; optionally, the heavy chain constant region is selected from the group consisting of a heavy chain constant region of any one of IgG1, igG2, igG3, igG4, igA, igM, igE, igD, or a combination of constant regions, and/or the light chain constant region is selected from the group consisting of kappa-type or lambda-type light chain constant regions; Optionally, the heavy chain constant region comprises CH1 of IgG1, a hinge region of IgG1, CH2 of IgM, CH3 of IgM, and/or CH4 of IgM; optionally, the antibody comprises the following constant regions: A heavy chain constant region having an amino acid sequence as set forth in SEQ ID NO. 17, and a light chain constant region having an amino acid sequence as set forth in SEQ ID NO. 18, or an amino acid sequence having at least 80% identity to each of said constant regions.
  6. 6. An antibody for detecting beta-amyloid protein, which is characterized by comprising a heavy chain and a light chain, wherein the heavy chain has an amino acid sequence shown in any one of SEQ ID NO. 23, 24, 25, 26, 46 and 66, and the light chain has an amino acid sequence shown in any one of SEQ ID NO. 28, 48 and 68; Optionally, the amino acid sequences of the heavy chain and the light chain are selected from any one of the groups (A ')to (C'): (A') a heavy chain having an amino acid sequence shown in any one of SEQ ID NO. 23, 24, 25, 26, and a light chain having an amino acid sequence shown in SEQ ID NO. 28; (B') a heavy chain having an amino acid sequence shown as SEQ ID NO. 46, and a light chain having an amino acid sequence shown as SEQ ID NO. 48, and (C') a heavy chain having an amino acid sequence shown in SEQ ID NO. 66, and a light chain having an amino acid sequence shown in SEQ ID NO. 68.
  7. 7. An antibody pair for detecting beta-amyloid protein, characterized in that the antibody pair comprises a coated antibody and/or a labeled antibody, wherein the coated antibody and the labeled antibody are respectively selected from the antibodies of any one of claims 1 to 6; Alternatively, the coated antibody comprises a first antibody selected from the group consisting of the antibody of claim 2 (C '), the antibody of claim 4 (C) or the antibody of claim 6 (C'), and a second antibody selected from the group consisting of the antibody of claim 2 (a '), the antibody of claim 4 (a) or the antibody of claim 6 (a') Alternatively, the labeled antibody is selected from the group consisting of the antibody of (B ') set of claim 2, the antibody of (B) set of claim 4, or the antibody of (B') set of claim 6; Optionally, the labeled antibody is labeled with a detectable label and/or binding partner; optionally, the detectable label is selected from the group consisting of metal ions, fluorescent dyes, enzymes, radioisotopes, chemiluminescent labels, electron dense labels, adamantane, and nanoparticle-based labels; Optionally, the label is an acridinium ester; Optionally, the coated antibody is attached to a solid support and/or binding partner; Optionally, the solid phase is selected from microspheres, magnetic beads, latex particles, microfluidic chips, plates or membranes; alternatively, the solid phase is selected from magnetic beads; Alternatively, the binding partner comprises a biotin/avidin or biotin derivative/avidin derivative protein.
  8. 8. A detection reagent or kit for detecting β -amyloid, characterized in that the reagent or kit comprises the antibody of any one of claims 1 to 6 or the antibody pair of claim 7.
  9. 9. A method of detecting β -amyloid comprising: a) Contacting an antibody according to any one of claims 1 to 6, an antibody pair according to claim 7 or a reagent or kit according to claim 8 with a sample to be tested under conditions sufficient for an antibody/antigen binding reaction to take place, to form an immune complex, and B) Detecting the presence of the immune complex, the presence of the complex being indicative of the presence of beta-amyloid in the test sample.
  10. 10. Use of the antibody of any one of claims 1 to 6, the antibody pair of claim 7 or the reagent or kit of claim 9 for detecting β -amyloid or for preparing a product for detecting β -amyloid.

Description

Antibody for detecting beta-amyloid and application thereof Technical Field The invention relates to the technical field of immunodiagnosis, in particular to an antibody for resisting detection of beta-amyloid and application thereof. Background Alzheimer's Disease (AD), senile dementia, is one of the most common neurodegenerative diseases in the elderly population. The pathogenesis and etiology of AD is currently unknown, and among many hypotheses, the amyloid cascade hypothesis (amyloid cascade hypothesis) is the main theory that the overproduction or untimely elimination of β -amyloid (aβ), such as aβ1-42 or other aβ polypeptide fragments, in the brain is thought to lead to the deposition of soluble aβ oligomers and insoluble amyloid proteins in the brain forming amyloid plaques, playing an important pathological role in the course of AD. Clinically, by using amyloid positron emission tomography (positron emission tomography, PET) (Abeta-PET for short), pre-clinical patients and MCI patients without symptoms can be identified early, and the differential diagnosis accuracy of dementia patients can be improved. However, PET imaging is a non-clinical routine examination, and has a large limitation, particularly in primary hospitals where the popularity is low, accessibility is poor, and charging is expensive. In recent years, research into Abeta as a body fluid marker of AD has been significantly progressed, with Abeta 1-40 and Abeta 1-42 being the most important. Aβ1-42 is a small 4kDa protein of about 40 amino acids that is formed after proteolytic cleavage of the transmembrane protein of the amyloid precursor. The type of sample studied initially was cerebrospinal fluid (cerebrospinal fluid, CSF), and generally the content of Abeta 1-40 in CSF is about 10 times that of Abeta 1-42. In AD patients, the concentration of Abeta 1-40 is not generally significantly changed, while the concentration of Abeta 1-42 is significantly decreased. Multiple studies demonstrated that the ratio of Abeta 1-42/Abeta 1-40 was more accurate than Abeta 1-42 alone in diagnosing AD from non-AD. Because CSF detection requires lumbar puncture operation, the sampling mode is complex and has problems of complications such as headache and the like, minimally invasive, convenient and low-cost blood detection is receiving more and more attention. The specific and sensitive overlap between clinical CSF and plasma aβ values and between the latter and aβ -PET has been widely accepted. The immune detection method is widely applied to detection of the biomarker due to simple operation, high sensitivity and strong specificity. Common immunodetection methods include colloidal gold methods, fluorescence methods, chemiluminescence methods, and the like, which all require specific antibodies to antigens. In particular, in healthy normal humans, the concentration ranges of Aβ1-40 and Aβ1-42 in blood are 100 pg/mL-400 pg/mL and 15 pg/mL-30 pg/mL, respectively. However, since the level of Abeta 1-42 in AD patients is decreased, an immunological detection method is required to accurately and precisely quantify Abeta 1-42 at a low concentration in blood, and a raw material antibody excellent in performance is required. In addition, some immunoassays require a partner antibody to be effective, and thus the partner antibody to β -amyloid is also critical for achieving immunoassays. Currently, there is a lack of antibodies and paired antibodies on the market that have a performance advantage, which limits the accuracy and reliability of beta-amyloid detection. There is a strong need in the art for antibodies and paired antibodies that have strong binding properties and high sensitivity. Disclosure of Invention The application provides an antibody, which provides an important raw material source for detecting beta-amyloid and has good detection performance. In order to achieve the above object, according to a first aspect of the present invention, there is provided an antibody for detecting β -amyloid, which comprises three heavy chain complementarity determining regions HCDR1, HCDR2 and HCDR3 in the heavy chain variable region shown in any one of SEQ ID NOs 19, 20, 21, 22, 45, 65 and three light chain complementarity determining regions LCDR1, LCDR2 and LCDR3 in the light chain variable region shown in any one of SEQ ID NOs 27, 47, 67. In order to achieve the above object, according to a second aspect of the present invention, there is provided an antibody for detecting β -amyloid, the complementarity determining region of the antibody comprising any one of the groups (a ') to (c'): The amino acid sequence of (a') is shown as HCDR1 shown in SEQ ID NO 1 (AYYIH) and SEQ ID NO 2 in sequence (RIDPATGNTKYAPRLQD) or 15 (RLDPATGNTKYAPRLQD), HCDR2 shown in SEQ ID NO:3 (LYSLPVY) or 16 (IYSLPVY), and HCDR3 shown in SEQ ID NO:4 in that order (KSSQSLLYSDAKTYLN) LCDR1, LCDR2 shown in SEQ ID NO 5 (QISRLDP), LCDR3 shown in SEQ ID NO 6 (LQGTHYPVL); (b') the amino acid s