A meningococcal outer membrane protein synthetic peptide and its application

Abstract

This application relates to the technical field of biomedicine, and particularly to a meningococcal outer membrane protein synthetic peptide and its application. This application discloses a meningococcal outer membrane protein synthetic peptide and its application. The amino acid sequence of the polypeptide is at least one of (I) to (IV): (I) the amino acid sequence shown in SEQ ID NO.1; (II) the amino acid sequence shown in SEQ ID NO.2; (III) the amino acid sequence shown in SEQ ID NO.3; (IV) the amino acid sequence shown in SEQ ID NO.4. This application discloses a meningococcal outer membrane protein synthetic peptide and its application, and discloses the polypeptide sequence. The vaccine made from this polypeptide or its polymer can effectively cope with the antigen diversity of meningococcal PorA and PorB, is easy to synthesize on a large scale, and has good application prospects.

Description

Technical Field

[0001] This application relates to the technical field of biomedicine, and particularly to a meningococcal outer membrane protein synthetic peptide and its application. Background Art

[0002] Meningococcus is the main cause of epidemic cerebrospinal meningitis (meningococcal meningitis) and fulminant septicemia, and is also the only pathogenic bacterium that can cause meningococcal meningitis. There are 13 different serogroups of meningococcus, among which groups A, B, C, Y and W135 are the main pathogenic serogroups.

[0003] Currently, a variety of membrane components and extracellular components are applied to the development of meningococcal vaccines, including class 1, 2 and 3 outer membrane proteins (porin proteins), class 4 outer membrane proteins (Rmp proteins) and class 5 outer membrane proteins (Opacity proteins). PorA protein is a class P1 outer membrane protein, and PorB protein is a class P2 or P3 outer membrane protein, and both are expressed by Neisseria meningitidis. PorA and PorB are key antigens, which have been used in vaccine preparations and are considered to be ideal antigens for inducing effective bactericidal antibodies. However, meningococcus effectively escapes the immune response through antigenicity and phase variation. For example, the secondary structures of PorA and PorB proteins show that both have 8 exposed loop structures (loopⅠ to Ⅷ). Among them, loopⅠ and Ⅳ are the variable regions of PorA, while loopⅠ, Ⅴ, Ⅵ and Ⅶ are the variable regions of PorB, and the antigenic determinants that determine the serum subtypes and serotypes of strains mainly exist in the variable regions of both. PorA and PorB, whose highly immunogenic surface loops are the main reasons for inducing non-wide protective immune responses, make the Por proteins derived from specific meningococcal strains tend to preferentially provide immunity against that specific strain.

[0004] Therefore, in order to effectively cope with the antigen diversity of meningococcal PorA and PorB, it is crucial to develop novel polypeptides for synthesizing meningococcal outer membrane protein synthetic peptide vaccines. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, this application provides a meningococcal outer membrane protein synthetic peptide and its application, specifically relating to a polypeptide or its polypeptide polymer for a meningococcal outer membrane protein synthetic peptide vaccine, as well as a vaccine containing the polypeptide or its polypeptide polymer and the application of the vaccine.

[0006] This application discloses a meningococcal outer membrane protein synthetic peptide and its application. The vaccine prepared from the polypeptide or its polymer can effectively cope with the antigen diversity of meningococcal PorA and PorB, is easy to synthesize on a large scale, and has good application prospects.

[0007] In a first aspect, the present application provides a polypeptide, adopting the following technical solution:

[0008] By analyzing the protein sequences of eleven domestic Neisseria meningitidis serogroup B strains, studying the variation of porA and porB antigenic sites, and combining computer-aided methods for the analysis and prediction of porA and porB antigenic sites, a conserved antigenic site polypeptide sequence is obtained. The amino acid sequence of the polypeptide is at least one of (I) to (IV):

[0009] (I) The amino acid sequence shown in SEQ ID NO.1;

[0010] (II) The amino acid sequence shown in SEQ ID NO.2;

[0011] (III) The amino acid sequence shown in SEQ ID NO.3;

[0012] (IV) The amino acid sequence shown in SEQ ID NO.4;

[0013] (V) A sequence having at least 90% homology with the sequences described in (I) to (IV);

[0014] (VI) An amino acid sequence obtained by substituting, deleting or adding one or two amino acid sequences to the amino acid sequence shown in any one of (I) to (V), and having the same or similar function as the amino acid sequences shown in (I) to (V).

[0015] Further preferably, the amino acid sequence of the polypeptide is the sequence shown in SEQ ID NO.1 to 4.

[0016] In a second aspect, the present application provides a polypeptide polymer, adopting the following technical solution:

[0017] A polypeptide polymer, comprising a polypeptide; the amino acid sequence of the polypeptide is at least one of (I) to (IV):

[0018] (I) The amino acid sequence shown in SEQ ID NO.1;

[0019] (II) The amino acid sequence shown in SEQ ID NO.2;

[0020] (III) The amino acid sequence shown in SEQ ID NO.3;

[0021] (IV) The amino acid sequence shown in SEQ ID NO.4;

[0022] (V) A sequence having at least 90% homology with the sequences described in (I) to (IV);

[0023] (VI) An amino acid sequence obtained by substituting, deleting, or adding one or two amino acid sequences to the amino acid sequence shown in any one of (I) to (V), and having the same or similar function as the amino acid sequences shown in (I) to (V).

[0024] More preferably, the amino acid sequence of the polypeptide is the sequence shown in SEQ ID NO.1 - 4.

[0025] Preferably, it further includes a carrier protein.

[0026] Preferably, the carrier protein includes at least one of albumin, porin, diphtheria toxin, tetanus toxin, heat - labile enterotoxin, and ferritin.

[0027] In a third aspect, the present application provides an application of a polypeptide or a polypeptide polymer in the preparation of a synthetic peptide vaccine of Neisseria meningitidis outer membrane protein, adopting the following technical solution:

[0028] The application of the above - mentioned polypeptide or the above - mentioned polypeptide polymer in the preparation of a synthetic peptide vaccine of Neisseria meningitidis outer membrane protein.

[0029] In a fourth aspect, the present application provides a synthetic peptide vaccine of Neisseria meningitidis outer membrane protein, adopting the following technical solution:

[0030] A synthetic peptide vaccine of Neisseria meningitidis outer membrane protein, comprising the above - mentioned polypeptide or the above - mentioned polypeptide polymer.

[0031] Preferably, the vaccine further includes an immune adjuvant.

[0032] More preferably, the immune adjuvant includes at least one of aluminum adjuvant, squalene, tocopherol, MPL, LPA, CpG, and QS - 21.

[0033] In a fifth aspect, the present application provides a preparation method of a polypeptide, adopting the following technical solution:

[0034] A preparation method of a polypeptide, the steps of the preparation method are as follows:

[0035] Using resin as the starting material, in the presence of a basic reagent, connect the amino acid at the C - terminal of the peptide with an α - amino protecting group to the resin;

[0036] Remove the protecting group with a de - capping reagent;

[0037] Connect each amino acid constituting the peptide in sequence from the C - terminal to the N - terminal of the peptide for reaction, thereby forming a peptide - linked resin, and then perform peptide cleavage and purification of the crude product to obtain the polypeptide.

[0038] In a specific feasible embodiment, a method for preparing a polypeptide comprises the following steps:

[0039] (1) Deprotection reaction: React in a solution of N-methylpyrrolidone with 15%-30% (by volume) of piperidine at 20-28 °C for 25-40 minutes to remove the 9-fluorenylmethoxycarbonyl protecting group on the resin amino group. Blow dry with nitrogen and wash with N-methylpyrrolidone.

[0040] (2) Activation of amino acids: React each amino acid with 9-fluorenylmethoxycarbonyl protecting group used for synthesis with 1-hydroxybenzotriazole to synthesize amino acid-1-hydroxybenzotriazole ester.

[0041] (3) Condensation reaction: Use a polypeptide synthesizer to automatically add the above various amino acids, resin, and diisopropylcarbodiimide to the reactor, and react at 20-28 °C for 0.5-2.5 hours. Blow dry with nitrogen and wash the resin with N-methylpyrrolidone.

[0042] (4) Acetylation reaction: React a solution of N-methylpyrrolidone with 1.5%-4% (g / mL) of acetylimidazole with the resin obtained in step (3) at 20-28 °C for 20-40 minutes. Blow dry with nitrogen and wash the resin with methanol.

[0043] (5) The synthesis process is from the C-terminus to the N-terminus, and steps (1)-(4) are continuously repeated according to the amino acid sequence. After the reaction is completed, wash with N-methylpyrrolidone to obtain dry polypeptide resin.

[0044] (6) Separation of polypeptide and resin: Add a cleavage reagent to the dry polypeptide resin, stir evenly for 1-4 hours, then react at 0 °C for 10 minutes, restore to room temperature, evaporate trifluoroacetic acid, add tert-butyl methyl ether and diethyl ether to the polypeptide solution, stir and wash, and filter to obtain a polypeptide solution.

[0045] (7) Ultrafiltration purification of polypeptide and aseptic treatment: Ultrafilter the polypeptide at 20-28 °C using a membrane package, and sterilize and preserve it using a 0.22-micron in-line filter.

[0046] Preferably, the cleavage reagent includes trifluoroacetic acid, triisopropylsilane, ethanedithiol, phenol, and water; the volume ratio of trifluoroacetic acid, triisopropylsilane, ethanedithiol, phenol, and water is 85:8:3:3:1.

[0047] In a sixth aspect, the present application provides a method for preparing a polypeptide polymer, adopting the following technical solution:

[0048] A method for preparing a polypeptide polymer, the steps of the preparation method are as follows:

[0049] After activating the carrier protein with sodium 3 - sulfo - N - hydroxysuccinimide 4 - (N - maleimidomethyl) cyclohexane - 1 - carboxylate, filter and desalt to obtain the activated carrier protein;

[0050] Mix each sequence of the polypeptide in equal proportion to obtain a polypeptide mixture;

[0051] Couple the polypeptide mixture with the activated carrier protein to obtain a polypeptide polymer.

[0052] Preferably, the mass ratio of sodium 3 - sulfo - N - hydroxysuccinimide 4 - (N - maleimidomethyl) cyclohexane - 1 - carboxylate to the carrier protein is (0.5 - 1):(3 - 7).

[0053] Preferably, the volume - mass ratio of the polypeptide mixture to the activated carrier protein is (0.1 - 1) mL:(4 - 8) mg.

[0054] In this application, by designing a conservative PorA protein polypeptide, the immune response is mainly directed against conservative epitopes, and the immunogenicity of the synthetic polypeptide is enhanced by coupling to a carrier protein carrier, so that the vaccine containing the synthetic polypeptide provides a broader - spectrum immune protection against Neisseria meningitidis strains.

[0055] In a seventh aspect, this application provides an application of a meningococcal outer membrane protein synthetic peptide vaccine, adopting the following technical solution:

[0056] An application of a meningococcal outer membrane protein synthetic peptide vaccine, the application includes at least one of the following:

[0057] (1) Application in the preparation of a drug for preventing and / or treating diseases caused by Neisseria meningitidis;

[0058] (2) Application in the preparation of a drug for preventing and / or treating epidemic cerebrospinal meningitis;

[0059] (3) Application in the preparation of a drug for preventing and / or treating fulminant septicemia.

[0060] In summary, this application includes at least one of the following beneficial technical effects:

[0061] This application discloses a meningococcal outer membrane protein synthetic peptide and its application, and discloses the polypeptide sequence. The vaccine made from this polypeptide or its polymer can effectively cope with the antigen diversity of meningococcal PorA and PorB, is easy to synthesize on a large scale, and has good application prospects. Brief Description of the Drawings

[0062] Figure 1 It is a graph showing the results of ELISA detection of antigen - specific serum IgG;

[0063] Figure 2 It is the result graph of ELISA for detecting antigen-specific secretory IgA. Specific implementation mode

[0064] For the experimental methods without specified specific conditions in the following examples of this application, they are usually in accordance with conventional conditions or in accordance with the conditions recommended by the manufacturer; for the experimental materials and reagents involved in the following content, if not otherwise specified, they are commercially available products.

[0065] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those skilled in the technical field to which this application belongs. The terms used in the description of this application are only for the purpose of describing specific embodiments and are not used to limit this application.

[0066] The terms "comprising" and "having" in this application and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, device, product or equipment that includes a series of steps is not limited to the listed steps or modules, but optionally further includes steps not listed, or optionally further includes other steps inherent to these processes, methods, products or equipment.

[0067] Next, the technical solution of this application will be clearly and completely described in conjunction with specific embodiments. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the protection scope of this application.

[0068] Example 1: Solid-phase synthesis of polypeptide antigen of meningococcal outer membrane protein synthetic peptide vaccine

[0069] This example is prepared by the Merrifield solid-phase synthesis method. The solid-phase carrier is Rink Amide MBHA resin; the instrument is an ABI 433A automatic polypeptide synthesizer.

[0070] 1. Preparation of synthesis raw materials:

[0071] The sequences of the polypeptides of the meningococcal outer membrane protein synthetic peptide vaccine are the amino acid sequences shown in SEQ ID NO.1, SEQ ID NO.2, SEQ ID NO.3, and SEQ ID NO.4.

[0072] Prepare appropriate 9-fluorenylmethoxycarbonyl (Fmoc)-modified amino acids according to the above polypeptide antigen sequence and a synthesis scale of 1 mmol, and add them to the corresponding Cartridge (vial for amino acids). Weigh Rink Amide MBHA resin as required, place it in the reaction chamber, and install the reaction chamber into the synthesizer. Place N-methylpyrrolidone (NMP), acetylimidazole (AIM), piperidine (PIP), methanol, etc. into the corresponding reagent bottles.

[0073] 2. Preparation of meningococcal outer membrane protein synthetic peptide:

[0074] (1) Deprotection reaction: React in a solution of N-methylpyrrolidone with 15%-30% (by volume) of piperidine at 20-28 °C for 25-40 minutes to remove the 9-fluorenylmethoxycarbonyl protecting group on the resin amino group, blow dry with nitrogen, and wash with N-methylpyrrolidone;

[0075] (2) Activation of amino acids: React each amino acid with 9-fluorenylmethoxycarbonyl protecting group for synthesis with 1-hydroxybenzotriazole to synthesize amino acid-1-hydroxybenzotriazole ester;

[0076] (3) Condensation reaction: Use a polypeptide synthesizer to automatically add the above various amino acids, resin, and diisopropylcarbodiimide to the reactor, react at 20-28 °C for 0.5-2.5 hours, blow dry with nitrogen, and wash the resin with N-methylpyrrolidone;

[0077] (4) Acetylation reaction: React the resin obtained in step (3) with an N-methylpyrrolidone solution of acetylimidazole with a weight-volume percentage of 1.5%-4% (g / mL) at 20-28 °C for 20-40 minutes, blow dry with nitrogen, and wash the resin with methanol;

[0078] (5) The synthesis process is from the C-terminus to the N-terminus, and continuously repeat steps (1)-(4) according to the amino acid sequence. After the reaction is completed, wash with N-methylpyrrolidone to obtain dry polypeptide resin;

[0079] (6) Separation of polypeptide and resin: Add a cleavage reagent (volume ratio of each component: trifluoroacetic acid: triisopropylsilane: ethanedithiol: phenol: water = 85:8:3:3:1) to the dry polypeptide resin, stir evenly for 1-4 hours, then react at 0 °C for 10 minutes, restore to room temperature, evaporate trifluoroacetic acid, add tert-butyl methyl ether and diethyl ether to the polypeptide solution, stir and wash, and filter to obtain a polypeptide solution;

[0080] (7) Ultrafiltration purification of polypeptide and aseptic treatment: Ultrafilter the polypeptide at 20-28 °C using a membrane package, and sterilize and store using a 0.22 μm in-line filter.

[0081] Example 2: Preparation of polypeptide polymer

[0082] A method for preparing a polypeptide polymer comprises the following steps:

[0083] (1) Take the albumin solution, filter it through a 0.45 μm filter membrane, measure UV280, and obtain an albumin solution with a concentration of 1 mg / mL;

[0084] (2) Weigh 4-(N-maleimidomethyl)cyclohexane-1-carboxylic acid 3-sulfo-N-hydroxysuccinimide ester sodium salt (Sulfo-SMCC), dissolve it in water to obtain a Sulfo-SMCC solution with a concentration of 4 mg / mL;

[0085] (3) Add 0.2 mL of the Sulfo-SMCC solution to 5 mL of the albumin solution, let it stand and react at room temperature in the dark for 2 h; then filter through a 0.2 μm filter and desalt to remove the excess Sulfo-SMCC to obtain the activated albumin;

[0086] (4) Mix the amino acid sequences shown in SEQ ID NO.1, SEQ ID NO.2, SEQ ID NO.3, and SEQ ID NO.4 in a mass ratio of 1:1:1:1 to obtain a polypeptide mixture;

[0087] (5) Dissolve 6 mg of the polypeptide mixture in 0.6 mL of 1×PBS (pH 7.2) solution, detect the sulfhydryl groups in the polypeptide with Ellman's reagent, and measure its ultraviolet absorption value OD value > 0.15 at λ = 412 nm with a Nano spectrophotometer;

[0088] (6) Add 0.6 mL of the polypeptide mixture solution obtained in step (5) to about 6 mg of the activated albumin, let it stand and react at room temperature in the dark for 4 h;

[0089] (7) After the reaction, detect the sulfhydryl groups in the polypeptide with Ellman's reagent, and measure the ultraviolet absorption value OD value < 0.03 at λ = 412 nm, indicating that the crosslinking rate of the polypeptide and albumin has reached over 80%, and obtain the polypeptide polymer.

[0090] Example 3: Preparation of meningococcal outer membrane protein synthetic peptide vaccine

[0091] A method for preparing a meningococcal outer membrane protein synthetic peptide vaccine comprises the following steps:

[0092] Mix 200 μg of the polypeptide polymer prepared in Example 2 and 1 mL of CpG solution (concentration: 200 μg / mL) to obtain the meningococcal outer membrane protein synthetic peptide vaccine.

[0093] Example 4: Mouse Immunization and Immunogenicity Detection of Meningococcal Outer Membrane Protein Synthetic Peptide Vaccine

[0094] 1. Animal Immunization

[0095] (1) Female C57BL / 6 mice aged 6 - 8 weeks were selected for immunization; they were randomly divided into two groups, with 6 mice in each group, namely the CpG control group and the synthetic peptide vaccine group;

[0096] (2) Animals in the CpG control group were given CpG solution; animals in the synthetic peptide vaccine group were given the meningococcal outer membrane protein synthetic peptide vaccine prepared in Example 3. Each mouse was given 10 μg of polypeptide polymer antigen and 10 μg of CpG each time, and the injection volume was 50 μL / mouse. The specific grouping and numbering are shown in Table 1;

[0097] (3) The immunization method was nasal drip immunization. Each mouse was immunized 3 times, and the drops were instilled into the nasal cavity on the 1st day, 7th day, and 14th day respectively;

[0098] (4) One week after the last immunization, the mice were anesthetized and blood was collected from the tail and oral lavage fluid was taken.

[0099] Table 1 Grouping and Numbering of Immunized Mice

[0100]

[0101] 2. ELISA Detection of Antigen - Specific Serum IgG. The detection steps are as follows:

[0102] (1) Coating antigen: Dilute the meningococcal lysate with coating buffer to 10 μg / mL, and add 100 μL / well to a 96 - well enzyme - labeled plate, and coat overnight at 4°C;

[0103] (2) Blocking: Drain the coated enzyme - labeled plate, wash the plate 5 times with 300 μL / well of washing solution, pat dry, and add 300 μL / well of blocking solution (2% BSA) to the plate and incubate at 37°C for 2 hours;

[0104] (3) Dilution of standards and test samples: Dilute the standard (mouse IgG) with sample diluent to 200 ng / mL and perform 2 - fold serial dilution; dilute the test sample (serum from immunized mice) with PBS by 1000 - 10000 times;

[0105] (4) Adding samples: Drain the blocked enzyme - labeled plate, wash the plate 5 times with 300 μL / well of washing solution, pat dry, and add the samples (serially diluted standards and diluted test samples) from the dilution plate to the enzyme - labeled plate at 100 μL / well, and incubate at room temperature for 1.5 h;

[0106] (5) Add enzyme-labeled working solution: Dilute the HRP-labeled goat anti-mouse IgG antibody with the secondary antibody diluent; Spin dry the enzyme-linked immunosorbent assay (ELISA) plate, wash the plate 5 times with 300 μL of washing solution per well, pat dry, add the diluted secondary antibody to the ELISA plate at 100 μL / well, and incubate at room temperature for 1 h;

[0107] (6) Color development: Wash the plate 5 times with 300 μL of washing solution per well, spin dry. Wipe the bottom with absorbent paper. Move the chromogenic solution from the 4 °C refrigerator to room temperature and store it away from light 30 minutes in advance, add the chromogenic solution to each well at 100 μL / well, and develop color at room temperature away from light for 15 minutes;

[0108] (7) Termination: Add the termination solution to each well at 50 μL / well to terminate the reaction, and read the plate within 5 minutes;

[0109] (8) Read the plate: Place the ELISA plate into the microplate reader, set it to oscillate at medium speed for 10 seconds, and read the OD450.

[0110] The results are as Figure 1 shown. Compared with the control CpG group, the serum one week after immunization with the meningococcal outer membrane protein synthetic peptide vaccine contains a higher level of meningococcal-specific IgG antibodies.

[0111] 3. ELISA was used to detect antigen-specific secretory IgA, and the detection steps were as follows:

[0112] (1) Coating antigen: Dilute the meningococcal lysate with the coating solution to 10 μg / mL, add it to the 96-well ELISA plate at 100 μL / well, and coat it overnight at 4 °C;

[0113] (2) Blocking: Spin dry the coated ELISA plate, wash the plate 5 times with 300 μL of washing solution per well, pat dry, add the blocking solution (2% BSA) to the plate at 300 μL / well, and incubate at 37 °C for 2 h;

[0114] (3) Dilution of standards and test samples: Dilute the standard (mouse IgA) with the sample diluent to 200 ng / mL and perform 2-fold serial dilution; Dilute the test sample (oral lavage fluid from immunized mice) with PBS by 1000 - 10000 times;

[0115] (4) Adding samples: Spin dry the blocked ELISA plate, wash the plate 5 times with 300 μL of washing solution per well, pat dry, add the samples (serially diluted standards and diluted test samples) from the dilution plate to the ELISA plate at 100 μL / well, and incubate at room temperature for 1.5 h;

[0116] (5) Add enzyme-labeled working solution: Dilute the HRP-labeled goat anti-mouse IgA antibody with the secondary antibody diluent; Spin dry the enzyme-linked immunosorbent assay (ELISA) plate, wash the plate 5 times with 300 μL of washing solution per well, pat dry, add the diluted secondary antibody to the ELISA plate at 100 μL / well, and incubate at room temperature for 1 h;

[0117] (6) Color development: Wash the plate 5 times with 300 μL of washing solution per well, and drain. Wipe the bottom with absorbent paper. Move the color developer from the 4°C refrigerator to room temperature and store it in the dark 30 minutes in advance. Add 100 μL of color developer per well and develop color at room temperature in the dark for 15 minutes;

[0118] (7) Termination: Add the termination solution at 50 μL per well to terminate the reaction and read the plate within 5 minutes;

[0119] (8) Reading the plate: Place the enzyme-labeled plate into the microplate reader, set it to oscillate at medium speed for 10 seconds, and read the OD450.

[0120] The results are as Figure 2 shown. Compared with the control CpG group, the oral lavage fluid one week after immunization with the meningococcal outer membrane protein synthetic peptide vaccine contains a higher level of meningococcal-specific secretory IgA antibody.

[0121] The present application discloses a meningococcal outer membrane protein synthetic peptide and its application, and discloses the polypeptide sequence. The vaccine made of the polypeptide or its polymer can effectively cope with the antigen diversity of meningococcal PorA and PorB, is easy to synthesize on a large scale, and has good application prospects.

Claims

1. A method for preparing a polypeptide polymer, characterized in that: The preparation method steps are as follows: After activating the carrier protein with 4-(N-maleimidomethyl)cyclohexane-1-carboxylic acid 3-sulfo-N-hydroxysuccinimide ester sodium salt, filtering and desalting to obtain the activated carrier protein; Mixing the polypeptide sequences described in SEQ ID NO.1, SEQ ID NO.2, SEQ ID NO.3, and SEQ ID NO.4 in equal proportions to obtain a polypeptide mixture; The polypeptide mixture is coupled with the activated carrier protein to obtain a polypeptide polymer.

2. The method for preparing a polypeptide polymer according to claim 1, characterized in that: The mass ratio of the 4-(N-maleimidomethyl)cyclohexane-1-carboxylic acid 3-sulfo-N-hydroxysuccinimide ester sodium salt to the carrier protein is (0.5-1):(3-7).

3. The method for preparing a polypeptide polymer according to claim 1, characterized in that: The polypeptide mixture is dissolved in 0.6 mL 1×PBS at a concentration of 6 mg to prepare a solution, and the volume mass ratio of the polypeptide mixture solution to the activated carrier protein is (0.1-1) mL: (4-8) mg.

4. The method for preparing a polypeptide polymer according to claim 1, characterized in that: The carrier protein includes at least one of albumin, poracin, diphtheria toxin, tetanus toxin, heat-labile enterotoxin and ferritin.

5. A polypeptide polymer, characterized in that: The polypeptide polymer is prepared by the method according to any one of claims 1 to 4.

6. Use of the polypeptide polymer according to claim 5 in the preparation of antiserum binding to meningococcal lysate.

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