JP2009084199A - Anti-catechins antibody - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prepare an antibody which specifically recognizes catechins having a gallate group, and to provide a method for immunologically analyzing catechins having a gallate group, using the antibody. <P>SOLUTION: The antibody which specifically binds to catechins having a gallate group or a fragment bound to its antigen and a chimeric antibody or a recombinant antibody comprising the above fragment bound to the antigen (hereinafter referred to as "anti-catechins antibody or the like") are disclosed. A biosensor for detecting catechins having a gallate group is provided by immobilizing the anti-catechins antibody or the like and a method of detecting or determining catechins having a gallate group uses the biosensor or the anti-catechins antibody or the like. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an antibody against a catechin having a gallate group or an antigen-binding fragment thereof, a biosensor for detecting a catechin having a gallate group obtained by immobilizing the antibody or the antigen-binding fragment, and the antibody or an antigen-binding fragment thereof. And a method for detecting or measuring a catechin having a gallate group.

  The medicinal effects of green tea began with the discovery of cancer prevention effects in 1987, and have been developed until biochemical cell experiments, animal experiments, epidemiological studies, and even cancer prevention effects in humans have been proven. Various pharmacological activities such as antibacterial action, blood cholesterol lowering action and antiallergic action have also been reported.

The main soluble components of green tea are catechins having a flavan-3-ol skeleton among green tea polyphenols, (-)-epigallocatechin gallate (EGCG), (-)-epicatechin gallate (ECG), (-)- Epigallocatechin (EGC), (−)-epicatechin (EC), (−)-gallocatechin gallate (GCG), (−)-catechin gallate (CG), (±) -gallocatechin (GC), (±) -Presence of eight catechins of catechin (C) is known. The content of these catechins varies depending on the type of raw tea (Camellia sinensis), the cultivation conditions, and the processing method into green tea, but is generally 5 to 18% by weight (Non-patent Document 1).
Journal of Japanese Society for Food Science and Industry, Vol. 46, No. 3, pp. 138-147 (1999)

Recently, among catechins, (-)-epigallocatechin gallate (EGCG), (-)-epicatechin gallate (ECG), (-)-catechin gallate (CG) and (- ) -Gallocatechin gallate (GCG) has been reported to lower cholesterol in women by continuous ingestion (Non-patent Document 2).
Shuji Enomoto et al., Health Sci. Volume 22, Pages 60-71 (December 2005)

  Since catechins having a gallate group have the effects described above, it is important to study the body distribution, organ distribution, and intracellular distribution of catechins having a gallate group. However, in the past, methods were mainly used to administer radioisotope-labeled catechins and track their distribution dynamics, and reported immunological analysis using antibodies that specifically recognize catechins having gallate groups. Is not known. This is because an antibody that specifically recognizes catechins having a gallate group cannot be used.

  Therefore, it is necessary to create an antibody that specifically recognizes catechins having a gallate group, and to develop an immunological analysis method for catechins having a gallate group using the antibody.

  The present invention provides an antibody or an antigen-binding fragment thereof characterized by specifically binding to a catechin having a gallate group. The antibody of the present invention or an antigen-binding fragment thereof binds to (−)-epigallocatechin gallate, (−)-epicatechin gallate, (−)-catechin gallate and (−)-gallocatechin gallate, -Epigallocatechin, (-)-epicatechin, (±) -gallocatechin and (±) -catechin may not bind.

  The antibody of the present invention may be a monoclonal antibody.

  The present invention may provide a chimeric antibody or a recombinant antibody that specifically binds to catechins having a gallate group containing the antigen-binding fragment of the monoclonal antibody of the present invention.

  The present invention provides a biosensor for detecting a catechin having a gallate group in which the antibody of the present invention or an antigen-binding fragment thereof, a chimeric antibody or a recombinant antibody containing the antigen-binding fragment is immobilized.

  The present invention provides a method for detecting or measuring catechins having a gallate group. The method may include a step of measuring the presence / absence or binding amount of catechins having a gallate group to the catechin detection biosensor of the present invention by a surface plasmon resonance method. The method for detecting or measuring catechins having a gallate group of the present invention may include a step of binding the antibody of the present invention or an antigen-binding fragment thereof, a chimeric antibody or a recombinant antibody containing the antigen-binding fragment.

  In the present specification, catechins are catechins having a flavan-3-ol skeleton among green tea polyphenols, and (−)-epigallocatechin gallate (EGCG), (−)-epicatechin gallate (ECG), (− ) -Epigallocatechin (EGC), (−)-epicatechin (EC), (−)-gallocatechin gallate (GCG), (−)-catechin gallate (CG), (±) -gallocatechin (GC) and ( Including but not limited to molecular species such as ±) -catechin (C). In this specification, catechins having a gallate group are (−)-epigallocatechin gallate (EGCG), (−)-epicatechin gallate (ECG), (−)-catechin gallate (CG) and (−) —. Including but not limited to molecular species such as gallocatechin gallate (GCG). In the present specification, catechins having no gallate group include (−)-epigallocatechin (EGC), (−)-epicatechin (EC), (±) -gallocatechin (GC) and (±) -catechin ( Including but not limited to molecular species such as C).

  The catechins of the present invention are described in Fujiki, H. et al. And Okuda, T .; , (-)-Epigallocatechin gallate, Drugs and Future, 17 (6): 462-464, tea leaves are extracted with a 1: 1 solution of methanol and water and purified by column chromatography. EGCG may be further purified by recrystallization.

  The catechins of the present invention are prepared as a complex bound to a carrier polymer (hereinafter referred to as “catechins complex”) to produce the monoclonal antibody of the present invention and / or to detect or measure the catechins of the present invention. May be used to implement the method. The carrier polymer refers to any polymer that can confer immunogenicity to the hapten, and may be a biopolymer such as a protein or polysaccharide, or a synthetic polymer such as polylysine. Proteins used in the carrier polymer of the complex include, but are not limited to, bovine serum albumin, chicken ovalbumin, thyroglobulin, and keyhole limpet hemocyanin.

  The catechins and the carrier polymer in the complex may be bonded between any functional group of the catechins and the carrier polymer. For example, the amino group or carboxyl group of catechins may be covalently bonded to any side chain of the carrier polymer via an appropriate crosslinking agent. The crosslinking agent is glutaraldehyde (GA), N-hydroxysuccinimide (NHS), 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride (EDC), N- [ε-maleimidocaproyloxy]. Including succinimide ester (EMCS), succinimidyl 4- [N-maleimidomethyl] -cyclohexane-1-cacloxylate (SMCC) and N- [γ-maleimidobutyryloxy] succinimide ester (GMBS) Not limited. The cross-linking agent is, for example, Pierce Biotechnology, Inc. (Funakoshi Co., Ltd.) can be purchased.

  The antibody of the present invention includes a polyclonal antibody and a monoclonal antibody. The antibodies of the present invention may be derived from various species of animals including but not limited to mice, rats, goats, rabbits, horses, chickens, and humans.

An antigen-binding fragment of an antibody of the invention refers to the portion of the antibody that participates in antigen binding. The antigen binding site is formed by amino acid residues in the variable (V) region at the N-terminus of the heavy (H) chain and light (L) chain. Examples of the antigen-binding fragment include, but are not limited to, a Fab fragment, an F (ab ′) ₂ fragment, and an Fv fragment.

  The antibodies of the present invention may be prepared by various techniques known to those skilled in the art. See, for example, Harlow and Lane, Using Antibodies: A Laboratory Manual, Cold Spring Harbor Laboratory, 1999.

  When catechins are used as an immunogen for preparing the antibody of the present invention, a complex of a catechin and a carrier protein such as bovine serum albumin or mussel hemocyanin may be formed. The immunogen is preferably injected into the animal host according to a predetermined schedule incorporating one or more booster immunizations. The immunogen may be injected into the animal host mixed and / or emulsified with a complete or incomplete Freund's adjuvant or other immunopotentiator. Injection sites include, but are not limited to, subcutaneous, intraperitoneal, intravenous, intramuscular, and footpad.

  Monoclonal antibodies used in the present invention are described in Koehler and Milstein, Eur. J. et al. Immunol. 6: 511-519, 1976, and improved techniques thereof. These methods involve the preparation of immortal cell lines that can produce antibodies with the desired specificity. Such cell lines may be generated from cells derived from the spleen, lymph nodes or other organs of an animal host immunized as described above. The organ-derived cells are immortalized by various methods to prepare immortalized cell lines capable of producing antibodies. The organ-derived cells are immortalized by, for example, fusion with myeloma cells derived from the same or different species of the immunized animal. Various fusion techniques known to those skilled in the art may be used. For example, the organ-derived cells and myeloma cells are mixed with a nonionic surfactant for several minutes and then plated at a low concentration in a selective medium that supports hybrid cell growth but does not support myeloma cell growth. A preferred selection technique uses HAT (hypoxanthine, aminopterin, thymidine) selection. Hybrid colonies are observed after sufficient time, usually about 1 to 2 weeks. A single colony is selected and its culture supernatant is tested for binding activity against the polypeptide. Hybridomas with high reactivity and specificity are preferred. By repeating the cloning by the limiting dilution method, a hybridoma clone that stably produces a large amount of highly reactive and specific antibody is selected. Monoclonal antibodies may be isolated from the supernatants of colonies of cell lines derived from selected growing hybridoma clones. Furthermore, various techniques for improving the yield may be used, such as transplanting the hybridoma cell line into the peritoneal cavity of an appropriate vertebrate host such as a mouse. Monoclonal antibodies may be collected from ascites or blood of animals transplanted with the hybridoma cells. Contaminants or contaminants may be removed from the antibody by conventional techniques such as chromatography, gel filtration, precipitation and extraction.

Antigen-binding fragments of antibodies used in the present invention include Fv fragments in addition to Fab fragments or F (ab ′) ₂ fragments obtained by degrading immunoglobulins of monoclonal antibodies with the proteolytic enzyme papain or pepsin, respectively. The Fv fragment is a heterodimer composed of a subunit containing V _H and a subunit containing a _VL region, and contains an antigen binding site that retains much of the antigen recognition ability and binding ability of a natural antibody molecule. .

The recombinant antibodies used in the present invention may be prepared by expression cloning of antibody genes including transformation into a suitable bacterial host or transfection into a suitable mammalian cell host. The chimeric antibody used in the present invention is a fusion protein supported by the constant domain of the same or different antibody so that the antigen-binding site of the recombinant antibody of the present invention can specifically bind to catechins. The chimeric antibody used in the present invention includes a short chain variable region antibody (scFv) comprising an antibody heavy chain variable region (V _H ) operably linked to an antibody light chain variable region (V _L ), a camelid ( A camelid heavy chain antibody (HCAb), or a heavy chain variable region domain (VHH) thereof, which is a class of IgG without light chain produced by animals of Camelidae, camels, dromedaries, llamas). The recombinant antibodies of the present invention can be prepared in large quantities using prokaryotic and eukaryotic derived gene expression systems.

  The method for detecting or measuring catechins of the present invention may be detected or measured by a surface plasmon resonance method. The surface plasmon resonance method uses an optical phenomenon called surface plasmon resonance (SPR) on a solid support between a molecule immobilized on the solid support and a molecule that interacts with the molecule. This is a technique for measuring specific interaction in as a minute mass change. By applying this technique, a monoclonal antibody that specifically binds to the catechins of the present invention immobilized on a solid support, an antigen-binding fragment thereof, a chimeric antibody and a recombinant antibody (hereinafter referred to as “anti-catechin antibodies etc.”) The amount of catechins bound to the above can be quantified as the mass change of the solid support. As a system for performing the surface plasmon resonance method, for example, a Biacore system (Biacore Corporation) is commercially available.

  The catechins detection biosensor of the present invention is obtained by immobilizing the anti-catechin antibodies of the present invention on a measurement chip (hereinafter referred to as “SPR chip”) of the surface plasmon resonance (SPR) method. In the catechin detection biosensor of the present invention, the anti-catechin antibody of the present invention may be immobilized on the SPR chip by direct covalent bonding. Alternatively, the specific binding partner that specifically binds to the anti-catechin antibody or the like of the present invention is immobilized on the SPR chip by covalent bond, and the anti-catechin antibody or the like of the present invention specifically binds to the specific binding partner. May be immobilized on the SPR chip via The specific binding partner includes protein A or protein G that specifically binds to an antibody protein and a secondary antibody against a mouse antibody. When the anti-catechin antibody of the present invention is labeled with biotin, avidin is used as the specific binding partner. Instead of biotin and avidin, a His tag consisting of an amino acid sequence in which histidine residues are contiguous, a myc tag corresponding to the sequence of 10 amino acids 410 to 419 of the human c-myc protein, hemagglutinin of human influenza virus ( In some cases, a peptide tag such as an HA tag corresponding to 9 amino acids from No. 98 to No. 106 of HA) and an antibody that specifically binds to the peptide tag may be used. In order to label an anti-catechin antibody or the like with the peptide tag, in addition to binding the peptide tag to an anti-catechin antibody or the like by a covalent bond or the like, a chimeric antibody or a recombinant antibody containing the amino acid sequence of the peptide tag is used. May be created.

  The method for detecting or measuring catechins of the present invention includes immunohistochemical methods, immunocytochemical methods using an optical microscope or electron microscope, Western blotting method, ELISA method, chemiluminescent enzyme immunoassay method, fine particle or nano fine particle An analysis method based on a change in the turbidity due to the aggregation of selenium may be included, but may be detected or measured by an immunological analysis method that is not limited thereto. The method for immunological analysis of catechins of the present invention includes a method based on competitive binding and a method based on non-competitive binding. In order to detect and quantify catechins, the anti-catechin antibodies or the like of the present invention or catechins may be labeled with a low molecular ligand such as biotin, an enzyme, a radioisotope, a dye, etc. A secondary antibody against an anti-catechin antibody or a biopolymer such as avidin that specifically binds to a low-molecular ligand such as biotin may be labeled with an enzyme, a radioisotope, a dye, or the like. .

  The method for immunological analysis of catechins of the present invention uses a solid support to which the anti-catechin antibodies of the present invention are immobilized or a solid support to which catechins or a catechin complex is immobilized There is. The solid support is not particularly limited as long as it can be immobilized without losing the specific binding ability between the catechins or the catechins complex and the anti-catechins antibody, etc., and uses solids of various materials or shapes. be able to. The solid support may be fabricated from materials including but not limited to polymeric materials, glass, ceramics, gels, membranes, natural fibers, silicones, metals and composites thereof. The solid support includes shapes suitable for handling by automated diagnostic systems, such as multiwell plates, microtiter plates, multiarray chips, sensor chips, latex agglomeration microparticles or nanoparticles.

  The catechins or catechins complex of the present invention is not only immobilized on the solid support by electrostatic adsorption, but also the functional groups of the catechins or catechins complex and the functional groups of the solid support. May be immobilized on the solid support by a covalent bond.

  The method using competitive binding of the present invention comprises (1) a step of preparing the solid support, and (2) a step of preparing a mixed solution of a sample containing catechins and the anti-catechin monoclonal antibody. (3) contacting the mixed solution with the solid support; and (4) detecting and quantifying the anti-catechins monoclonal antibody bound to the solid support.

  In the method using competitive binding of the present invention, (1) the step of preparing the solid support includes the anti-catechin monoclonal antibody, the solid support on which the catechin complex is immobilized, The sample is prepared manually or automatically.

  In the method using competitive binding of the present invention, (2) in the step of preparing a mixed solution of a sample containing catechins and the anti-catechin monoclonal antibody, the catechins in the sample and the anti-catechins monoclonal antibody are prepared. Perform antigen-antibody reaction. Therefore, step (2) includes incubating the mixed solution under conditions sufficient to complete the antigen-antibody reaction between the catechins in the sample and the anti-catechin monoclonal antibody.

  In the method using competitive binding according to the present invention, (3) the step of bringing the mixed solution into contact with the solid support comprises the step of (3) catechins of a catechin complex immobilized on the solid support, The anti-catechin monoclonal antibody that did not react with the catechins in the sample in 2) undergoes an antigen-antibody reaction. Accordingly, in the step (3), an antigen-antibody reaction between the catechins of the catechin complex immobilized on the solid support and the anti-catechin monoclonal antibody that did not react with the catechins in the sample. Incubating the mixed solution under conditions sufficient to complete.

  In the method using competitive binding according to the present invention, (4) the step of detecting and quantifying the anti-catechin monoclonal antibody bound to the solid support comprises the steps of detecting and quantifying the anti-catechin monoclonal antibody not bound to the solid support. May be included by washing. The anti-catechin monoclonal antibody is detected and / or quantified by a label such as the monoclonal antibody or the secondary antibody. The step of quantifying comprises preparing a calibration curve in which the amount of the anti-catechin monoclonal antibody reacted with the catechins of the solid support is quantified using a sample containing catechins of a known concentration, and an unknown Steps (1) to (3) are performed on a sample containing a concentration of catechins, and the concentration of catechins in the sample is calculated from the amount of the anti-catechin monoclonal antibody bound to the solid support using the calibration curve. Steps.

  The calibration curve of the present invention refers to a graph or relational expression that correlates the concentration of catechins in a sample with the amount of anti-catechin monoclonal antibody that has reacted with the catechins of the solid support. There should be at least two samples containing catechins with known concentrations used for the preparation of a calibration curve, but it is desirable that the number is three or four or more from the viewpoint of ensuring quantitative accuracy.

  The method for quantifying the amount of the anti-catechin monoclonal antibody that has reacted with the catechins of the solid support is not particularly limited, but includes an ELISA method and a surface plasmon resonance (SPR) method as well as a latex agglutination method.

  The ELISA method detects the target antibody by binding an enzyme-labeled secondary antibody against an anti-catechin antibody or the like to the anti-catechin antibody or the like, adding a substrate for the labeled enzyme, and detecting an enzyme reaction product. It is a method to quantify. In some cases, instead of using a secondary antibody, a low molecular ligand such as biotin is bound to the anti-catechin antibody or the like, and then a biopolymer such as avidin that specifically binds to the low molecular ligand is used. is there. Examples of the enzyme label used for the labeling include peroxidase (POD), beta-galactosidase (β-gal), alkaline phosphatase (ALP), and the like, which are detected by a color development reaction or chemiluminescence reaction using an appropriate substrate.

  In the latex agglutination method, the degree of agglomeration reaction of fine particles according to the amount of monoclonal antibody bound to fine particles or nanoparticles such as latex as a solid support is measured with a spectrophotometer as a change in turbidity.

  The present invention will be described in more detail with reference to the following examples. However, these examples are given by way of example for detailed description of the present invention, and the scope of the present invention is limited by these examples. Should not be understood.

1.1 Purification of catechins Tea leaves were extracted with a 1: 1 solution of methanol and water and purified on columns of DIAION HP-20, Toyopearl HW-40 and MCL gel CHP-20P. Elution was performed by increasing the concentration of methanol and ethanol with respect to water. (−)-Epigallocatechin gallate was further purified by recrystallization.

1.2 Preparation of catechin complex A catechin complex (hereinafter referred to as “KHL-catechin”) obtained by covalently binding purified catechins and mussel hemocyanin (KHL) or thyroglobulin (TG) with a crosslinking agent. And TG-catechins) were dialyzed against 50 mM sodium phosphate buffer (pH 6.0).

1.3 Immunization of animals Emulsified by mixing catechin complex (1 mg / mL) with KHL or TG as a carrier polymer and Freund's complete adjuvant (RM606-1, Mitsubishi Chemical Yatron) in the same volume. And were administered to the foot pads of four female individuals of each Balb / c strain mouse. The first immunization is the first day, the second and third immunizations are performed on the 4th and 7th days, respectively, the lymph nodes are removed on the 10th day, and internal lymphocytes are removed. And myeloma cell P3U1 were fused.

1.4 Screening of hybridoma clones After cell fusion, the cells were cultured in a 96-well plate, subjected to normal HAT selection, and the catechin complex used as an immunogen was adsorbed to the culture supernatant of wells in which colony formation was observed. It was screened by ELISA for the presence of antibodies that bind to the solid support. A positive colony was isolated and cloned by limiting dilution in a 96-well plate to obtain a clone that stably produces an antibody that binds to the catechin complex.

2. Results From the cell fusion between the lymphocytes of 4 mice immunized with KHL-catechins and TG-catechins and the myeloma cell line P3U1, colony formation was observed in about 800 wells. When immunized with KHL-catechins, four types of hybridoma clones that were confirmed by ELISA to produce antibodies that bind to the KHL-catechins used as the immunogen were obtained. When immunized with TG-catechins, 38 hybridoma clones producing antibodies that bind to TG-catechins were obtained.

1. Analysis of Monoclonal Antibody by Surface Plasmon Resonance Method The antibody produced by the hybridoma clone obtained in Example 1 was analyzed by the surface plasmon resonance method in order to examine the specificity of binding to catechins.

  For analysis of surface plasmon resonance, Biacore system (Biacore Corporation) was used. According to the manufacturer's instructions, S. aureus derived protein A was immobilized covalently on a CM5 sensor chip. Next, the hybridoma supernatant was passed through the sensor chip, and the monoclonal antibody in the hybridoma supernatant was immobilized on the sensor chip via protein A. In this state, catechins of different molecular species were flowed through the sensor chip at different concentrations, and the specificity of binding between the catechins and the monoclonal antibody was examined from the change in the resonance value of surface plasmon resonance.

2. Results A clone producing a monoclonal antibody that specifically binds to catechins could not be confirmed in the hybridoma using KHL-catechins as an immunogen. Only one type of clone producing a monoclonal antibody that specifically binds to catechins could be confirmed as a hybridoma using TG-catechins as an immunogen.

  FIG. 1 shows surface plasmon resonance when (−)-epigallocatechin gallate (EGCG) was passed through a sensor chip in which clones TG6, TG38 and TG60 of hybridomas using TG-catechins as an immunogen were immobilized. It is a wave form diagram which shows the change of a resonance value. The horizontal axis is time (unit: second), the time when EGCG flows into the sensor is set to 0, and after 120 seconds, a buffer solution that does not contain EGCG flows into the sensor. The vertical axis represents the resonance value of surface plasmon resonance. As shown in FIG. 1, since the waveform of TG6 does not change even when EGCG flows into the sensor, it can be seen that the monoclonal antibody TG6 does not interact with EGCG at all. In the waveform of TG60, when EGCG flows into the sensor, the resonance value slightly increases, and it can be seen that the monoclonal antibody TG60 interacts with EGCG somewhat. However, when switching to a buffer solution that does not contain EGCG, the resonance value quickly decreases to the baseline level, so the binding between monoclonal antibody TG60 and EGCG is not strong. On the other hand, since the resonance value of the TG38 waveform significantly increases when EGCG flows in, the interaction between the monoclonal antibody TG38 and EGCG is quite strong. Even when a buffer solution containing no EGCG flows into the sensor, the resonance value is higher than the baseline level, indicating that a certain amount of EGCG is retained while bound to the monoclonal antibody TG38.

  FIGS. 2 and 3 are waveform diagrams showing changes in the resonance value of surface plasmon resonance when each of the molecular species of catechins is allowed to flow through a sensor chip in which TG38 is immobilized via protein A at different concentrations. EGCG, (−)-epicatechin gallate (ECG), (−)-catechin gallate (CG), (−)-gallocatechin gallate (GCG), (−)-epigallocatechin (EGC), (−)-epi Catechin (EC), (±) -gallocatechin (GC) and (±) -catechin (C) at concentrations of 1 mM, 0.5 mM, 0.33 mM, 0.25 mM, 0.125 mM and 0.1 mM, respectively. The result of an experiment in which TG38 is allowed to flow into the immobilized sensor chip and a buffer solution containing no catechins is allowed to flow in after 120 seconds is shown. From FIG. 2, it was found that EGCG, ECG, CG and GCG showed a strong interaction with monoclonal antibody TG38. From FIG. 3, it was found that EGC, EC, GC and C show little or no interaction with monoclonal antibody TG38.

  From the above results, it was shown that the monoclonal antibody TG38 specifically binds to catechins having a gallate group such as EGCG, ECG, CG and GCG, and most strongly binds to EGCG. The TG38 isotype was IgG2a. Since EGCG is a major component of the catechins contained in the tea extract, the monoclonal antibody TG38 is used in the body distribution, organ distribution, and intracellular distribution of catechins having a gallate group ingested by drinking tea. Useful as a reagent to study distribution.

The surface plasmon resonance waveform figure which shows the interaction of EGCG and a monoclonal antibody. The surface plasmon resonance waveform diagram which shows that a part of molecular species of catechin and the monoclonal antibody TG38 specifically bind. The surface plasmon resonance waveform figure which shows that another part of molecular species of catechin and the monoclonal antibody TG38 do not couple | bond together.

Claims (7)

  An antibody or an antigen-binding fragment thereof, which specifically binds to catechins having a gallate group.   It binds to (-)-epigallocatechin gallate, (-)-epicatechin gallate, (-)-catechin gallate and (-)-gallocatechin gallate, but (-)-epigallocatechin gallate, (-)-epicatechin The antibody or antigen-binding fragment thereof according to claim 1, which does not bind to (±) -gallocatechin and (±) -catechin.   The antibody or antigen-binding fragment thereof according to claim 1 or 2, wherein the antibody is a monoclonal antibody.   A chimeric or recombinant antibody comprising the antigen-binding fragment according to claim 3 and specifically binding to a catechin having a gallate group.   For detecting catechins having a gallate group, wherein the antibody or antigen-binding fragment thereof according to any one of claims 1 to 3 or the chimeric antibody or recombinant antibody according to claim 4 is immobilized. Biosensor.   A method for detecting or measuring a catechin having a gallate group, comprising the step of measuring the presence or amount of binding of a catechin to the catechin detection biosensor according to claim 5 by a surface plasmon resonance method.   A step of binding the immobilized catechin to the antibody or antigen-binding fragment thereof according to any one of claims 1 to 3 or the chimeric antibody or the recombinant antibody according to claim 4 is provided. A method for detecting or measuring catechins having a gallate group.

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