CN118005785A

CN118005785A - Novel tandem nanobodies for disease treatment

Info

Publication number: CN118005785A
Application number: CN202311865808.1A
Authority: CN
Inventors: 刘广洋; 刘拥军; 王荷蕊; 陈瑶瑶; 米一; 苗丽
Original assignee: Beijing Beilai Pharmaceutical Co ltd
Current assignee: Beijing Beilai Pharmaceutical Co ltd
Priority date: 2023-12-29
Filing date: 2023-12-29
Publication date: 2024-05-10

Abstract

The invention belongs to the field of antibodies, and particularly relates to a novel serial nanometer antibody for treating diseases. The novel serial nano antibody is a bivalent single-domain antibody, and is obtained by coupling a first single-domain antibody (1-C3) and a second single-domain antibody (2-G4) through a linker; the amino acid sequence of the heavy chain CDR region of the first single domain antibody is SEQ ID NO.1-3; the amino acid sequence of the heavy chain CDR region of the second single domain antibody is SEQ ID NO.4-6. The bivalent single domain antibody provided by the invention has good affinity and blocking effects and strong stability, provides important basis for diagnosis and treatment of inflammatory diseases, infectious diseases, autoimmune diseases, nervous system diseases and/or tumors, and has good application prospect.

Description

Novel tandem nanobodies for disease treatment

Technical Field

The invention belongs to the field of antibodies, and particularly relates to a novel serial nanometer antibody for treating diseases.

Background

Multivalent antibodies are polymers of monovalent antibodies that recognize the same epitope, with higher antigen affinity than monovalent antibodies; the multispecific antibody is a polymer of monovalent antibodies recognizing different epitopes, can bind different targets or different epitopes of the same target, has higher antigen recognition capability than the monovalent antibodies, and has higher effectiveness, lower drug resistance, wider application range given by new functions and lower toxicity than the monoclonal antibody combination.

The problem of chain mismatch is a unique technical difficulty in the development of bispecific antibody drugs and is one of the initial challenges encountered in the development of bispecific antibodies. Natural antibodies are composed of four polypeptide chains, the two larger molecular weight chains being referred to as heavy chains (H chains) and the two smaller molecular weight chains being referred to as light chains (L chains). In the monoclonal antibody structure, the amino acid compositions of the two heavy chains and the light chain are identical, and only one structure exists after the four chains are combined. However, unlike monoclonal antibodies, the purpose of simultaneously and specifically binding 2 different antigens is achieved by co-expressing two different heavy chains and two different light chains, so that in the process of assembling four chains, 16 possible structural combinations can be randomly generated by 2 heavy chains and 2 light chains, and even after the structures which are mirror images of each other are combined, 10 different antibody structures still exist, but only one of the structures is a target product. Moreover, the biochemical properties of these 10 different diabody products are very similar, and thus the difficulty in separating the target product therefrom is great. This is not common in monoclonal antibody production, and is also the root cause of low production of monoclonal antibodies, impurity proteins, and high production cost.

Single domain antibodies contain only one heavy chain variable region (VHH) and two conventional CH2 and CH3 regions, but have very good stability, unlike engineered single chain antibody fragments (scFv), which are prone to sticking to each other and even aggregating into aggregates. More importantly, the VHH structure cloned and expressed alone has structural stability comparable to that of the original heavy chain antibody and binding activity to the antigen, and is the minimum unit known at present to bind to the target antigen.

The single-domain antibody has the advantages of simple structure, small molecular weight, stable structure, easy expression and the like, and the single-domain antibody only contains one heavy chain variable region, so that the mismatch of heavy chains and light chains in the process of preparing the double antibody by tetramers can be avoided, the universality design of the double-function single-domain antibody is realized, the complex design and production process like the traditional double antibody are not needed, and the original limitation of the double-antibody medicine is effectively overcome.

IL-17A is an inflammatory cytokine produced mainly by activated T cells, and acts on downstream effector cells to mediate various physiological processes, such as inflammatory reaction, coagulation process, bone remodeling and the like, and is closely related to various diseases of the body. The excessive expression of IL-17A can cause the occurrence and development of various diseases such as rachitis, rheumatoid arthritis, systemic lupus erythematosus, psoriasis, inflammatory bowel disease and the like. The specific medicines clinically available for the diseases are few, and the traditional treatment has the defects of slower effect, poor compliance and the like. IL-17A deletion or antibody neutralization IL-17A can effectively inhibit the pathological degrees of various autoimmune diseases, but the monoclonal antibody has complex structure and relatively poor stability, and can achieve a certain effect by repeated large-dose injection in use. Therefore, there is a need to develop a drug of bivalent single domain antibodies, which has high stability and strong affinity, and is expected to be used for diagnosis and treatment of autoimmune diseases.

In order to solve the problems, the invention provides an anti-IL-17A bivalent single domain antibody, which is formed by connecting two single domain antibodies in series through a linker. The bivalent antibody is easy to prepare, has better affinity and blocking effect, and has strong stability.

The present inventors have focused on the development of anti-IL-17A antibodies, further technical development based on the screened 9 single domain antibodies (filed in another application), resulting in 12 single domain antibody combinations with relatively improved affinity, blocking effect and stability, and separately claimed 12 different single domain antibody combinations based on the relevant regulations of patent law singleness.

The present invention is a patent application directed to one of the above 12 single domain antibody combination antibodies.

Based on the above, the inventors have developed a genetically modified stem cell technology and subsequent application technology, and based on the relevant regulations of the patent law singleness, the protection is respectively requested for 3 different genetically modified stem cells and 3 different applications.

For the convenience of understanding the technical solution of the present application, reference is optionally made to other patent application documents of this project.

Disclosure of Invention

In the present invention, a single domain antibody is an antibody whose complementarity determining region is part of a single domain polypeptide. Thus, a single domain antibody comprises a single complementarity determining region. Single domain antibodies are heavy chain-only antibodies that naturally do not contain a light chain, single domain antibodies derived from conventional antibodies, and engineered antibodies. The single domain antibodies may be derived from any species including mice, humans, camels, llamas, goats, rabbits, and cattle. For example, naturally occurring VHH molecules may be derived from antibodies provided by camelidae species (e.g. camels, dromedaries, llamas and dromedaries). Like whole antibodies, single domain antibodies are capable of selectively binding to a particular antigen. A single domain antibody may contain only the variable domains of an immunoglobulin chain, which domains have CDR1, CDR2 and CDR3, as well as framework regions.

In the present invention, the anti-IL-17A bivalent single domain antibody, i.e., anti-IL-17A bivalent single domain antibody, includes not only the intact bivalent single domain antibody but also fragments, derivatives and analogues of the anti-IL-17A bivalent single domain antibody. Wherein fragments, derivatives and analogs are synonymous, all refer to polypeptides that retain substantially the same biological function or activity of an antibody of the invention. The polypeptide fragment, derivative or analogue of the present invention may be a polypeptide having one or more conserved or non-conserved amino acid residues (preferably conserved amino acid residues) substituted, and such substituted amino acid residues may or may not be a polypeptide encoded by the genetic code or having a substituent in one or more amino acid residues, or a polypeptide formed by fusion of a mature polypeptide with another compound (such as a compound that extends the half-life of the polypeptide, e.g. polyethylene glycol), or a polypeptide formed by fusion of an additional amino acid sequence to the polypeptide sequence (such as a leader sequence or secretory sequence or a pro-protein sequence for purification of the polypeptide, or a fusion protein with an Fc tag).

In the present invention, the CDR (complementary-DETERMINING REGIONS, CDR) is called a complementarity determining region or complementarity determining region. It is located in the hypervariable region of an immunoglobulin, which is the antigen binding site of an antibody, complementary to the structure of an epitope. Generally including CDR1, CDR2, CDR3. It will be appreciated by those skilled in the art that unless otherwise specified, the terms "CDR" and "complementarity determining region" of a given antibody or region thereof (e.g., variable region) are to be understood as encompassing complementarity determining regions defined in any of the above known schemes as described by the present invention. Although the scope of the present disclosure is based on the sequences shown by IMGT definition rules, amino acid sequences corresponding to other CDR definition rules shall also fall within the scope of the present invention.

In the present invention, the variable region refers to a region of the immunoglobulin light chain and heavy chain where the amino acid sequence changes greatly near the N-terminus, and is referred to as a variable region.

In the present invention, sequence homology means the degree to which two (nucleotide or amino acid) sequences have identical residues at identical positions in an alignment, and is generally expressed as a percentage. Preferably, homology is determined over the entire length of the sequences being compared. Thus, two copies with identical sequences have 100% homology. In some embodiments, sequences that replace only one or a few amino acids, e.g., comprising 1,2,3,4, 5, 6,7, 8, 9, or 10 conservative amino acid substitutions, as compared to the preceding sequences, may also achieve the object. These variants include, but are not limited to: deletion, insertion and/or substitution of one or more (usually 1 to 50, preferably 1 to 30, more preferably 1 to 20, most preferably 1 to 10) amino acids, and addition of one or several (usually 20 or less, preferably 10 or less, more preferably 5 or less) amino acids at the C-terminal and/or N-terminal end. In fact, the skilled person may consider so-called "conservative" amino acid substitutions, which in the case of substitution would preferably be conservative amino acid substitutions, in determining the degree of sequence homology between two amino acid sequences or in determining the CDR1, CDR2 and CDR3 combinations in a single domain antibody. The conserved amino acid, which may be generally described as an amino acid substitution of an amino acid residue with another amino acid residue having a similar chemical structure, has little or no effect on the function, activity, or other biological property of the polypeptide. Such conservative amino acid substitutions are common in the art, e.g., conservative amino acid substitutions are those in which one or a few amino acids in the following groups (a) - (d) are substituted for another or a few amino acids in the same group: (a) a polar negatively charged residue and an uncharged amide thereof: asp, asn, glu, gln; (b) a polar positively charged residue: his, arg, lys; (c) aromatic residues: phe, trp, tyr; (d) aliphatic nonpolar or low polar residues: ala, ser, thr, gly, pro, met, leu, ile, val, cys. Particularly preferred conservative amino acid substitutions are as follows: asp is substituted with Glu; asn is substituted with Gln or His; glu is substituted with Asp; gln is substituted with Asn; his is substituted with Asn or Gln; arg is replaced by Lys; lys is substituted by Arg, gln; phe is substituted with Met, leu, tyr; trp is substituted with Tyr; tyr is substituted with Phe, trp; substitution of Ala with Gly or Ser; ser is substituted by Thr; thr is replaced by Ser; substitution of Gly with Ala or Pro; met is substituted with Leu, tyr or Ile; leu is substituted with Ile or Val; lie is substituted with Leu or Val; val is substituted with Ile or Leu; cys is replaced by Ser. In addition, those skilled in the art will recognize that the creativity of single domain antibodies is represented in the CDR1-3 regions, while the framework region sequences FR1-4 are not immutable, and that the sequences of FR1-4 may take the form of conservative sequence variants of the sequences disclosed herein.

In the present invention, the Fc fusion antibody refers to a novel recombinant protein produced by fusing a functional protein molecule having biological activity with an Fc fragment using a genetic engineering technique or the like, which not only retains the activity of the functional protein molecule, but also has some antibody properties such as prolonged half-life by binding to a related Fc receptor, induction of antibody-dependent cell-mediated cytotoxicity effects, and the like. Wherein, the Fc fragment refers to a polypeptide composed of CH2 and CH3 domains of IgA, igD and gG, or composed of CH2, CH3 and CH4 domains of IgE and IgM via a hinge region.

In the present invention, a humanized antibody refers to an antibody obtained by fusing a heavy chain variable region of a target antibody (e.g., an animal antibody) to a constant region of a human antibody, or an antibody obtained by grafting a complementarity determining region (CDR 1-3 sequence) of a target antibody into a variable region of a human antibody, or an antibody obtained by mutating an amino acid of a target antibody according to the characteristics of a human antibody framework region (FR 1-4). Humanized antibodies can be synthesized or site-directed mutagenesis.

In the present invention, recombinant protein refers to a protein obtained by applying recombinant DNA or recombinant RNA technology. Recombinant protein engineering uses gene cloning or chemical synthesis technology to obtain target Gene (GOI), connects to proper expression vector, introduces into specific host cell, and uses host cell genetic system to express functional protein molecule. The recombinant protein reagent can be applied to the research and development and the production of biological drugs, cell immunotherapy and diagnostic reagents. The recombinant protein medicine is an important component of biological medicine, and can be applied to the medical field, including cytokines, antibody therapeutic vaccines, hormones, enzymes and the like.

Eukaryotic cells in the present invention refer to cells that contain a eukaryotic cell (a nucleus surrounded by a nuclear membrane). The chromosome number is more than one, and mitosis can be performed. It is also possible to perform both the protoplasm flow and the deformation movement. Photosynthesis and oxidative phosphorylation are performed by chloroplasts and mitochondria, respectively. All animal cells and plant cells, except for bacterial and cyanobacteria cells, are eukaryotic cells.

In the present invention, a prokaryotic cell is a cell constituting a prokaryote. The main characteristics of the cells are that the cells are not provided with nuclei which are bounded by nuclear membranes, are not provided with nucleoli, and are provided with pseudonuclei. The evolutionary position is low. The organelle is ribosomal only, has a cell membrane, and has a composition different from that of eukaryotic cells. The cells are smaller, have no shaped nuclei, have no chromosomes, and the DNA does not bind to proteins.

In the present invention, expression vectors refer to a type of vector in which some expression elements (such as promoters, terminators, etc.) are added to the basic skeleton of a cloning vector, so that the inserted exogenous DNA (target gene) can be replicated, transcribed and translated in a host cell.

In the present invention, the host cell is also called a recipient cell. The receptor cells include prokaryotic receptor cells (most notably E.coli), eukaryotic receptor cells (most notably yeast), animal cells and insect cells (in fact eukaryotic receptor cells as well). Among prokaryotic receptor cells, the most commonly used host cell is E.coli.

In the invention, pharmaceutically acceptable auxiliary materials refer to excipients and additives used in the production of medicines and the preparation of prescriptions; are substances which, apart from the active ingredient, have been reasonably evaluated in terms of safety and are contained in pharmaceutical preparations. The pharmaceutical excipients not only form, serve as carriers and improve stability, but also have important functions of solubilization, dissolution assistance, sustained and controlled release and the like, and are important components which can influence the quality, safety and effectiveness of the medicine.

In the present invention, EC50 refers to the half maximal effect concentration (concentration for 50%of maximal effect), i.e. the concentration that causes 50% of the maximal effect (herein "ability to bind IL-17A").

In the present invention, IC50 refers to the half inhibitory concentration (half maximal inhibitory concentration), i.e., the concentration that causes 50% of the maximum inhibitory effect (herein, "ability to inhibit IL-17A and its receptor IL-17RA binding").

In one aspect, the invention provides an antibody comprising the following (a) and (b):

(a) A first single domain antibody comprising HCDR1, HCDR2 and HCDR3; the amino acid sequences of the HCDR1, the HCDR2 and the HCDR3 are shown in SEQ ID NO. 1-3; and/or a sequence having at least 80% sequence identity to the sequences shown in SEQ ID NOS.1-3;

(b) A second single domain antibody comprising HCDR4, HCDR5 and HCDR6; the amino acid sequences of the HCDR4, the HCDR5 and the HCDR6 are shown as SEQ ID NO. 4-6; and/or a sequence having at least 80% sequence identity to the sequence shown in SEQ ID NO. 4-6.

Specifically, the amino acid sequence of the antibody comprises an amino acid sequence obtained by at least one of addition, deletion, modification or substitution on the amino acid sequences shown in SEQ ID NOS.1-6.

Further specifically, the amino acid sequence of the antibody comprises an amino acid sequence having a difference of 1,2,3, 4, 5, 6, 7, 8, 9, 11, 12, 13, 14, 15 or 16 amino acids compared to the amino acid sequence shown in SEQ ID nos. 1 to 6.

Specifically, the first single domain antibody or the second single domain antibody further comprises at least 4 heavy chain framework regions for linking the heavy chain variable regions.

Further specifically, the heavy chain framework region comprises a portion or all of an antibody heavy chain framework region selected from human, murine, primate, or camelid sources or a variant thereof;

Preferably, the antibody heavy chain framework regions or variants thereof comprise part or all of a source selected from camelids;

further preferred, comprises part or all of an antibody heavy chain framework region selected from alpaca sources or variants thereof.

In yet another aspect, the present invention provides an antibody comprising the following (a) and (b):

(a) A first single domain antibody, the structure of said first single domain antibody being:

FR1-HCDR1-FR2-HCDR2-FR3-HCDR3-FR4；

(b) A second single domain antibody, said second single domain antibody having the structure:

FR5-HCDR4-FR6-HCDR5-FR7-HCDR6-FR8；

Specifically, the amino acid sequences of HCDR1, HCDR2 and HCDR3 are selected from sequences shown in SEQ ID NO.1-3 or having 1,2,3, 4, 5,6, 7, 8, 9, 10, 11, 12, 13, 14, 15 or 16 amino acid differences compared to SEQ ID NO. 1-3;

the amino acid sequences of HCDR4, HCDR5 and HCDR6 are selected from sequences shown in SEQ ID NO.4-6 or having 1,2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 or 16 amino acid differences compared with SEQ ID NO. 4-6;

The amino acid sequences of FR1, FR2, FR3 and FR4 are selected from the sequences shown in SEQ ID NO.7-10 or having at least 80%, 85%, 90%, 95%, 96%, 97%, 98% or 99% sequence identity with SEQ ID NO. 7-10;

The amino acid sequences of FR5, FR6, FR7 and FR8 are selected from the group consisting of those shown in SEQ ID NO.11-14 or sequences having at least 80%, 85%, 90%, 95%, 96%, 97%, 98% or 99% sequence identity to SEQ ID NO. 11-14;

More specifically, the amino acid difference is achieved by at least one of addition, deletion, modification and/or substitution on the amino acid sequences shown in SEQ ID NO.1-3 and SEQ ID NO. 4-6.

Preferably, the amino acid sequence of the HCDR1 is shown as SEQ ID NO. 1; the amino acid sequence of the HCDR2 is shown as SEQ ID NO. 2; the amino acid sequence of the HCDR3 is shown as SEQ ID NO. 3; the amino acid sequence of the HCDR4 is shown as SEQ ID NO. 4; the amino acid sequence of the HCDR5 is shown as SEQ ID NO. 5; the amino acid sequence of the HCDR6 is shown as SEQ ID NO. 6.

Specifically, the amino acid sequences of the first single domain antibody and the second single domain antibody are directly linked or indirectly linked through a linker.

Further specifically, the linker is (GGGGS) n, wherein n is selected from 1, 2, 3, 4, 5 or 6; preferably, the linker is (GGGGS) 3.

Specifically, the linking sequence of the antibody is selected from one of the following (a) - (c):

(a) The first single domain antibody and the second single domain antibody are connected in an optional sequence;

(b) The first single domain antibody and the second single domain antibody are connected in the order from the N end to the C end;

(c) The first single domain antibody and the second single domain antibody are linked in order from the C-terminus to the N-terminus.

In particular, the antibody is an anti-IL-17A antibody.

In yet another aspect, the invention provides a recombinant protein comprising the aforementioned antibody.

In particular, the recombinant protein further comprises a biologically active protein or functional fragment thereof that aids in its expression and/or secretion, or that extends its half-life in vivo.

Further specifically, the biologically active polypeptide or functional fragment thereof is selected from at least one of an immunoglobulin Fc domain, serum albumin, albumin binding polypeptide, prealbumin, carboxy terminal peptide, elastin-like polypeptide, his tag, GST tag, MBP tag, FLAG tag, and SUMO tag.

Further specifically, the Fc domain is derived from a human antibody, a murine antibody, a primate antibody or a camelid antibody, or a variant thereof;

Preferably, the immunoglobulin Fc domain is derived from a human IgG antibody, e.g., igG1 Fc, igG2 Fc, igG3 Fc or IgG4 Fc, preferably IgG1 Fc.

In yet another aspect, the present invention provides an antibody preparation comprising the following (a) and (b):

(a) The aforementioned antibody or recombinant protein;

(b) A pharmaceutically acceptable carrier.

Specifically, the pharmaceutically acceptable carriers include, but are not limited to: buffers, sterile water or surfactants.

In yet another aspect, the invention provides a kit comprising an antibody or recombinant protein or antibody preparation as described above;

Specifically, the kit further comprises a container for loading the antibody preparation.

Specifically, the kit further includes, but is not limited to: solid phase carriers, detection labels, detection substrates and/or buffers.

Further specifically, the solid support may be a material having affinity that immobilizes the specific antibody on the surface.

The detection label may be an enzyme label, which is an enzyme capable of binding to an antibody, for detecting binding of the antibody to an antigen.

The detection substrate may be a reaction product of an enzyme label capable of producing a measurable signal under enzymatic catalysis.

In yet another aspect, the present invention provides a drug conjugate comprising the following (a) and (b):

(a) The aforementioned antibody or recombinant protein;

(b) A coupling moiety coupled to (a).

In yet another aspect, the invention provides an isolated nucleic acid molecule encoding an antibody or recombinant protein as described above.

In yet another aspect, the invention provides an expression vector comprising the nucleic acid molecule as described above.

In yet another aspect, the invention provides a pharmaceutical composition comprising an antibody or recombinant protein or antibody preparation or drug conjugate or nucleic acid molecule or expression vector as described above;

Specifically, the pharmaceutical composition further comprises at least one pharmaceutically acceptable auxiliary material.

Preferably, the pharmaceutically acceptable auxiliary materials are selected from polysorbate, histidine, sucrose, arginine, sodium chloride, methionine, acetate, trehalose, proline, sorbitol, sodium phosphate, poloxamer 188, ethylenediamine tetraacetic acid, citric acid, mannitol, glutamate, glycine, sodium citrate, sodium succinate and/or lactic acid.

In yet another aspect, the invention provides at least one of the aforementioned antibodies or recombinant proteins or antibody preparations or drug conjugates or pharmaceutical compositions for use in (a) - (c) as follows:

(a) Preparing a detection reagent or a kit;

(b) Preparing a medicament for preventing and/or treating autoimmune diseases;

(c) Preparing medicine for preventing and/or treating cancer.

In particular, the autoimmune diseases include, but are not limited to: behcet's disease, systemic lupus erythematosus, chronic discoid lupus erythematosus, multiple sclerosis, systemic scleroderma, progressive systemic sclerosis, scleroderma, polymyositis, dermatomyositis, perinodular arteritis, aortitis syndrome, malignant rheumatoid arthritis, juvenile idiopathic arthritis, spondyloarthritis, mixed connective tissue disease, kalman's disease, sjogren's syndrome, adult Steve's disease, vasculitis, allergic granulomatous vasculitis, allergic vasculitis, rheumatoid vasculitis, macrovasculitis, ANCA-related vasculitis, cogan syndrome, RS3PE syndrome, temporal arteritis, polymyalgia rheumatica, fibromyalgia, antiphospholipid antibody syndrome, eosinophilic fasciitis, igG 4-related diseases, guillain-Barre syndrome, myasthenia gravis, chronic atrophic gastritis, autoimmune hepatitis, inflammatory bowel disease non-alcoholic steatohepatitis, primary biliary cirrhosis, good-pasture syndrome, acute glomerulonephritis, lupus nephritis, megaloblastic anemia, autoimmune hemolytic anemia, pernicious anemia, autoimmune neutropenia, idiopathic thrombocytopenic purpura, barcedo's disease, hashimoto's disease, autoimmune adrenocortical insufficiency, primary hypothyroidism, addison's disease, idiopathic Addison's disease, type I diabetes, slowly progressive type I diabetes, focal scleroderma, psoriasis, psoriatic arthritis, bullous pemphigoid, pregnancy herpes, linear IgA bullous dermatoses, acquired bullous epidermolysis, alopecia areata, white spot, neuromyelitis, chronic inflammatory demyelinating polyneuropathy, multifocal motor neuropathy, sarcoidosis, giant cell arteritis, amyotrophic lateral sclerosis, former disease, autoimmune optic neuropathy, idiopathic azoospermia, habitual abortion, inflammatory bowel disease, celiac disease, ankylosing spondylitis, severe asthma, chronic urticaria transplant immunity, familial mediterranean fever, eosinophilic chronic sinusitis, dilated cardiomyopathy, systemic mastocytosis or inclusion body myositis;

preferably, the autoimmune disease may be plaque psoriasis, rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis or lupus nephritis.

In particular, the cancers include, but are not limited to: basal cell carcinoma, cholangiocarcinoma, bladder carcinoma, bone cancer, breast cancer, peritoneal carcinoma, cervical cancer, cholangiocarcinoma, choriocarcinoma, connective tissue cancer, cancer of the digestive system, endometrial cancer, esophageal cancer, ocular cancer, head and neck cancer, gastric cancer, glioblastoma, liver cancer, renal cancer, laryngeal cancer, leukemia, liver cancer, lung cancer, lymphoma, melanoma, myeloma, neuroblastoma, oral cancer, ovarian cancer, pancreatic cancer, prostate cancer, retinoblastoma, rhabdomyosarcoma, rectal cancer, cancer of the respiratory system, salivary gland carcinoma, sarcoma, skin cancer, squamous cell carcinoma, testicular cancer, thyroid cancer, uterine cancer, cancer of the urinary system, B-cell lymphoma, chronic lymphoblastic leukemia, acute lymphoblastic leukemia, hairy cell leukemia or chronic myelogenous leukemia.

Specifically, the medicine also comprises pharmaceutically acceptable auxiliary materials.

Specifically, the pharmaceutical dosage forms include, but are not limited to: liquid solution only, lyophilized powder, prefilled syringe only, prefilled syringe, lyophilized powder, tablet, capsule, granule, spray.

In particular, the routes of administration include, but are not limited to: intraocular injection, intravenous injection, intramuscular injection, subcutaneous injection, nasal inhalation, and oral administration.

In yet another aspect, the invention provides a method for in vitro detection of IL-17A in a sample for non-diagnostic purposes, said method comprising the steps of:

s1, the antibody or the recombinant protein or the antibody preparation or the drug conjugate is contacted with a sample to be detected;

s2, detecting an antigen-antibody complex;

S3, judging a result.

In yet another aspect, the present invention provides a method of preventing and/or treating an autoimmune disease, the method comprising administering to a subject in need thereof a therapeutically effective amount of an antibody or recombinant protein or antibody preparation or drug conjugate of the foregoing.

In yet another aspect, the present invention provides a method of preventing and/or treating cancer, said method comprising administering to a subject in need thereof a therapeutically effective amount of an antibody or recombinant protein or antibody preparation or drug conjugate of the foregoing.

The invention has the technical effects that:

(1) The affinity is good, the binding capacity is higher than that of a positive antibody (Ixekizumab), and the target protein can be bound.

(2) The blocking effect is good, the Human IL-17A protein can be blocked to activate 293F-IL-17RA-IL-17Rc-ACT 1-NFkB-Luc, and the blocking effect is better than that of a positive antibody (Ixekizumab).

(3) The stability is strong, the thermal denaturation T _m value and the thermal denaturation T _agg value are higher, and the stability is higher than that of a positive antibody (Ixekizumab).

Drawings

FIG. 1 shows SDS-PAGE results of bivalent single domain antibodies (C3-G4).

FIG. 2 shows the results of antibody affinity ELISA assays for bivalent single domain antibodies (C3-G4) and Ixekizumab.

FIG. 3 shows the results of antibody affinity assays for bivalent single domain antibodies (C3-G4) and Ixekizumab.

FIG. 4 shows the results of blocking function experiments with bivalent single domain antibodies (C3-G4) and Ixekizumab.

FIG. 5 shows the results of a stability test for a bivalent single domain antibody (C3-G4).

FIG. 6 shows the results of Ixekizumab stability experiments.

Detailed Description

The present invention will be described in further detail with reference to the following examples, which are not intended to limit the present invention, but are merely illustrative of the present invention. The experimental methods used in the following examples are not specifically described, but the experimental methods in which specific conditions are not specified in the examples are generally carried out under conventional conditions, and the materials, reagents, etc. used in the following examples are commercially available unless otherwise specified.

The main instrument of the invention:

an electrotransport device (Eppendorf Multiporator);

A centrifuge (Thermo FRESCO-17);

constant temperature incubator (Shanghai extract macro DNP-9052);

Constant temperature shake incubator (refined Qi CO-O6U);

Ultra clean bench (Sujing Antai SW-CJ-1 FD);

PCR instrument (Applied Biosystems ABI 2720);

biosafety cabinet (halr, HR40-IIA 2);

a flow cytometer (Thermo Attune Nxt flow cytometer);

thermo 3111CO ₂ incubator;

ForteBio OCTET R2。

The main reagent of the invention:

SfiI(NEB,CAT#:R0123L)；

T4 DNA ligase(TaKaRa,CAT#:2011A)；

PrimeScript^TMII 1st Strand cDNA Synthesis Kit(TaKaRa,CAT#:6210B)；

NuHi power mix (Xinhai organism, cat#: NH 9303);

3M sodium acetate (pH 5.2-6) (Sigma, CAT#: 126-96-5);

DNA fragment recovery kit (TakaRa, CAT#: 9761);

glue recovery kit (Qiagen, CAT#: 28706);

the Tiangen plasmid large drawing kit (Tiangen, CAT#: DP 117);

HRP-Anti-M13(iCarTab)；

PE-anti-Human IgG(eBioscience,Cat#:12-4998-82)；

Rabbit anti-Llama IgG(H+L)Secondary Antibody[HRP](Novus，CAT#NBP1-75095)；

SS320 competence (iCarTab);

pComF phage display vector (iCarTab);

NHS-biotin(APExBIO,CAT#:A8002)；

HRP-Streptavidin(Boster,CAT#:BA1088)；

HRP-ProteinA(Boster，BA1080)；

ProABiosensors(Sartorius,CAT#:18-5010)；

PBS(Gbico,CAT#14190-250)；

DMEM(Gbico,CAT#41965-062)；

RPMI1640(Gbico,CAT#61870044)；

FBS(VivaCell,CAT#C04001-500)；

Genomic DNAPurification Kit(Lifetech，CAT#K0512)；

Mouse-IL-17A-His(ACRO，CT8-M5240)。

The primers used for screening, cloning VHH fragments and constructing nanobodies in the invention are designed by referring to the following documents:

Maass DR,Sepulveda J,Pernthaner A,Shoemaker CB.Alpaca(Lama pacos)as a convenient source of recombinant camelid heavy chain antibodies(VHHs).JImmunol Methods.2007;324(1-2):13-25.

Lin,J,Gu,Y,Xu,Y et al.Characterization and applications of nanobodies against Pseudomonas aeruginosa exotoxin a selected from single alpaca B cells.Biotechnol Biotechnol Equip 2020;34:1028–37.

Studies on design of singledomain antibodies by AlpacaVHH phage library and high throughput sequencing toconstruct Fab antibody purification system(http:

//hdl.handle.net/10232/00030916).

basic examples preparation of Single-Domain antibodies

1.1 Preparation of antigen

Adding a 6xHis tag to the C end of an IL-17 antigen (SEQ ID NO. 6), performing gene synthesis according to prokaryotic codon optimization, and subcloning the gene into a pET28a vector; after being verified by Sanger sequencing, the plasmid is extracted; transforming the recombinant plasmid into BL21 competent, inducing overnight with 0.5mM IPTG, and collecting bacterial liquid for cleavage; purifying the recombinant protein using a nickel column; purity of the target protein was checked by SDS-PAGE. The IL-17A antigen protein is refined and purified to have the purity of more than 90 percent.

Preparation of positive control antibody Ixekizumab

The method comprises the following steps:

(a) Gene synthesis of Ixekizumab heavy and light chain variable regions (heavy chain variable region sequence SEQ ID No.23, light chain variable region sequence SEQ ID No. 24), subcloning the heavy chain variable region into pcdna3.4-hig 4 (IgG 4 constant region amino acid sequence SEQ ID No. 25) vector, and subcloning the light chain variable region into pcdna3.4-hIgKc (hIgKc constant region amino acid sequence SEQ ID No. 27) vector; after verification by Sanger sequencing, the plasmid megapump kit is used for preparing the endotoxin-removing plasmid for standby.

(B) Taking the LVTransm transfection reagent and the heavy chain and light chain expression vector out of the refrigerator, thawing at room temperature, and blowing up and down by a pipetting gun to mix completely. The PBS buffer was removed and warmed to room temperature. Taking 2mL of PBS to one hole of a 6-hole plate, respectively adding 50 mug heavy chain and light chain expression vectors, fully and uniformly mixing the mixture up and down by a pipetting gun, adding 300 mug L LVTRANSM, immediately and uniformly mixing the mixture up and down by a pipetting device, and standing for 10 minutes at room temperature.

(C) The DNA/LVTransm complex was added to 100mL of 293F cells, gently swirled and thoroughly mixed, and the cells were placed in a 5% CO ₂ incubator at 37℃and incubated at 130 RPM.

(D) After continuous cultivation for 5-7 days, the culture supernatant was collected by centrifugation, filtered with a 0.45 μm filter membrane, and the filtrate was transferred to a sterile centrifuge tube and the antibody was purified using Protein A.

(E) SDS-PAGE detects purity of target antibody protein, purity >95%; SDS-PAGE detects the purity of the positive control antibody protein >95%.

The positive control antibody is used for detecting the binding capacity of the recombinant antigen, and the result shows that the positive antibody and the IL-17A antigen protein are well combined and can be used for subsequent immunization.

The procedure for purifying antibodies by Protein A is as follows:

1) Samples containing the target antibodies were added to the EP tube and mixed by gently inverting the tube.

2) EP tubes were mixed at room temperature or incubated on a rotator, (1-4 hours or overnight) and 100mM PMSF was added to prevent protein degradation.

3) The magnetic beads were collected using a magnetic separation rack and the supernatant was discarded. The supernatant was retained for analysis, if necessary.

4) To the EP tube, 1mL of binding/washing buffer was added and thoroughly mixed, the beads were collected using a magnetic rack and the supernatant was discarded, and the washing step was repeated three times.

5) To the EP tube, 500. Mu.L of elution buffer was added, and resuspended rapidly with pipetting or vortexing, and then incubated at room temperature (about 25 ℃) for 5 minutes either in a tumble mixer or by manually gently tumbling the EP tube.

6) Magnetic beads were collected using a magnetic separation rack and the supernatant containing the eluted antibodies was transferred to a clean EP tube.

7) Steps 1) and 2) were repeated twice.

8) To each 500. Mu.L of eluate, 1/10 of a neutralization buffer was added to neutralize the pH in order to maintain the biological activity of the antibody and avoid inactivation of the antibody. Buffer exchange can be performed by dialysis or desalting, if desired.

9) Binding/washing buffer: 1 XPBS, pH 7.0.

Elution buffer: (1) 0.1M glycine, pH 2-3; (2) 0.1M NaAc-HAc, pH 3.6.

Neutralization buffer: 1M Tris, pH 8.5.

Magnetic bead regeneration buffer: 0.1M NaOH.

SEQ ID NO.23：

QVQLVQSGAEVKKPGSSVKVSCKASGYSFTDYHIHWVRQAPGQGLEW MGVINPMYGTTDYNQRFKGRVTITADESTSTAYMELSSLRSEDTAVYYCARY DYFTGTGVYWGQGTLVTVSS;

SEQ ID NO.24：

DIVMTQTPLSLSVTPGQPASISCRSSRSLVHSRGNTYLHWYLQKPGQSPQ LLIYKVSNRFIGVPDRFSGSGSGTDFTLKISRVEAEDVGVYYCSQSTHLPFTFG QGTKLEIK;

SEQ ID NO.25：

ASTKGPSVFPLAPCSRSTSESTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTKTYTCNVDHKPSNTKVDKRVESKYGPPCPPCPAPEFLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSQEDPEVQFNWYVDGVEVHNAKTKPREEQFNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKGLPSSIEKTISKAKGQPREPQVYTLPPSQEEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSRLTVDKSRWQEGNVFSCSVMHEALHNHYTQKSLSLSLGK;

SEQ ID NO.27：

RTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQS GNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSF NRGEC.

1.2 Animal immunization Process

2 Alpacas (Alpaca) are immunized by the prepared recombinant antigen in a subcutaneous multipoint immunization mode, 6 times are immunized at intervals of 21 days, and peripheral blood is collected after 10 days of last immunization, and ELISA detection of immune titer is carried out.

1.2.1 Immunotiter detection

The immune titers of alpaca after 6 rounds of immunization all meet the requirements (see table 1).

TABLE 1 results of immunotiter assays

1.3 Construction of antibody Yeast library

The method comprises the following steps:

1.3.1PBMC isolation and VHH antibody fragment cloning

Collecting 100mL of peripheral blood anticoagulation sample, and separating PBMC cells by using lymphocyte separation liquid; RNA was extracted and reverse transcription was performed using PRIMESCRIPT ^TM II 1st Strand cDNA Synthesis Kit to prepare cDNA; the VHH fragment was PCR amplified.

(2) Construction of a single domain antibody yeast display library.

1.4 Yeast display library panning and screening Process

Using the prepared IL-17A antigen, incubation with streptavidin magnetic beads, adding yeast liquid to the antigen-bound magnetic beads, and spin incubation at 4 ℃ for 60 minutes for 2 rounds of magnetic sorting of the constructed yeast display library using streptavidin magnetic beads. After sorting, the saccharomycete liquid is coated on an SDCAA plate, monoclonal culture is selected, and flow analysis is carried out after 48h of induced expression. Incubation with Biotin-IL-17A-His for 1h, using PE STREPTAVIDIN for secondary antibody, and performing flow detection after incubation.

And according to the flow detection result, after the second magnetic separation, the yeast positive rate is 37.9%, positive clones are remarkably enriched, the separated products are directly coated on an SDCAA plate, and single clones are selected for flow detection.

1.5FACS screening procedure

After sorting, the saccharomycete liquid is coated on an SDCAA plate, monoclonal culture is selected, after induction expression is carried out for 48 hours, the monoclonal antibody is incubated with Biotin-antigen, and after incubation is completed, flow detection is carried out by using PE-strepitavidin for the secondary antibody.

FACS detects the binding condition of IL17A target monoclonal and target; and comparing the amino acid sequences of the candidate single-domain antibodies obtained by sequencing, and selecting candidate antibodies with different CDR region amino acid sequences to construct eukaryotic expression vectors.

1.6 Identification of antibody sequences

Enriching positive clones; selecting the enriched single gram drop, carrying out PHAGE ELISA identification, and carrying out sequencing analysis on clones to obtain the nucleic acid and amino acid sequence information of the candidate single domain antibody. 20 monoclonals are randomly selected for sequencing analysis, the sequence difference is large, and the library diversity is good. The potential post-translational modification sites were analyzed by the In silico method against the amino acid sequence information of the CDR regions of the candidate single domain antibodies.

According to the result of the monoclonal flow detection of the yeast, positive clones combined with IL-17A-His are selected to extract genome DNA, and the antibody sequence is obtained by PCR.

1.7 Antibody expression purification Process

ELISA selects positive clones, obtains VHH antibody sequences, performs gene synthesis, and purifies Protein A after genetic engineering expression. Antibody purity >90%.

1.8 Functional experiments

(1) ELISA detects the binding process of the recombinant antibody to the target protein.

(2) Single domain antibody blocking function assay.

(3) Stability experiments.

(4) The single domain antibody epitope detection shows that the single domain antibody (1-C3) and the single domain antibody (2-G4) have different antibody epitopes.

EXAMPLE 1 cloning and expression of antibodies and purification methods

The amino acid sequence of the CDR region of the first single domain antibody (1-C3) is SEQ ID NO.1-3; the amino acid sequence of the FR region is SEQ ID NO.7-10; the amino acid sequence of the single domain antibody (1-C3) is SEQ ID NO.15;

the amino acid sequence of the CDR region of the second single domain antibody (2-G4) is SEQ ID NO.4-6; the amino acid sequence of the FR region is SEQ ID NO.11-14; the amino acid sequence of the single domain antibody (2-G4) is SEQ ID NO.16.

The two single domain antibodies are different epitopes, and the bivalent single domain antibody of the embodiment is that a first single domain antibody (1-C3) is connected with a second single domain antibody (2-G4) through linker (GGGGSGGGGSGGGGS) (the amino acid sequence after connection is SEQ ID NO.17; the corresponding nucleic acid sequence is SEQ ID NO. 18), and then the hinge region (SEQ ID NO. 19) and the CH region (SEQ ID NO. 20) are connected. The amino acid sequence of the obtained bivalent single domain antibody (1-C3-2-G4) is SEQ ID NO.21, and the corresponding nucleic acid sequence is SEQ ID NO.22.

Among them, the bivalent single domain antibody (1-C3-2-G4) is simply called bivalent single domain antibody (C3-G4).

SEQ ID NO.1：GEDLGYYA；

SEQ ID NO.2：VTSSGSST；

SEQ ID NO.3：ASTILLCSDYISAFGT；

SEQ ID NO.4：GEKLDYFA；

SEQ ID NO.5：VTSSGSST；

SEQ ID NO.6：ASTILLCSDYISAFGT；

SEQ ID NO.7：DVQLVESGGGLVEPGESLRLSCAAP；

SEQ ID NO.8：IAWFRQAPGKEREVVSC；

SEQ ID NO.9：NYLSSVKDRFTISIDNAKNTVYLQMNSLKPEDTAVYYC；

SEQ ID NO.10：WGQGTQVTVAS；

SEQ ID NO.11：QVQLVESGGGLVQPGGSLRLSCAAS；

SEQ ID NO.12：IGWFRQAPGKEREVVSC；

SEQ ID NO.13：NYLSSVKDRFTISIDNAKNTVYLQMNSLKPEDTAIYYC；

SEQ ID NO.14：WGQGTQVTVAS；

SEQ ID NO.15：

DVQLVESGGGLVEPGESLRLSCAAPGEDLGYYAIAWFRQAPGKEREVVSCVTSSGSSTNYLSSVKDRFTISIDNAKNTVYLQMNSLKPEDTAVYYCASTILLCSDYISAFGTWGQGTQVTVAS;

SEQ ID NO.16：

QVQLVESGGGLVQPGGSLRLSCAASGEKLDYFAIGWFRQAPGKEREVVSCVTSSGSSTNYLSSVKDRFTISIDNAKNTVYLQMNSLKPEDTAIYYCASTILLCSDYISAFGTWGQGTQVTVAS;

SEQ ID NO.17：

DVQLVESGGGLVEPGESLRLSCAAPGEDLGYYAIAWFRQAPGKEREVVSCVTSSGSSTNYLSSVKDRFTISIDNAKNTVYLQMNSLKPEDTAVYYCASTILLCSDYISAFGTWGQGTQVTVASGGGGSGGGGSGGGGSQVQLVESGGGLVQPGGSLRLSCAASGEKLDYFAIGWFRQAPGKEREVVSCVTSSGSSTNYLSSVKDRFTISIDNAKNTVYLQMNSLKPEDTAIYYCASTILLCSDYISAFGTWGQGTQVTVAS;

SEQ ID NO.18：

gatgtgcagctggtggagtctgggggaggcttggtcgagcctggggaatctctgaggctctcctgtgcagcccctggagaggatttgggttattacgccatagcctggttccgccaggccccagggaaggagcgtgaggtagtctcatgtgtcacaagtagtggtagtagcacaaactatttaagttccgtgaaggaccgattcaccatctccatagacaacgccaagaacacggtatatctgcaaatgaacagcctgaaacctgaggacacagccgtttattactgtgcgtccactattctcctctgttcagattatatctctgcctttggcacctggggccaggggacccaggtcaccgtcgcctcgggaggcggaggatctggcggaggtggaagtggcggaggcggttctcaggtgcagctcgtggagtcggggggaggcttggtgcagcccgggggatctctgaggctctcgtgtgcagcctctggagagaaattggattattttgccataggctggttccgccaggccccagggaaggagcgtgaggtagtctcatgtgtcacaagtagtggtagtagcacaaactatttaagttccgtgaaggaccgattcaccatctccatagacaacgccaagaacacggtatatctgcaaatgaacagcctgaaacctgaggacacagccatttattactgtgcgtccactattctcctctgttcagattatatctctgcctttggcacctggggccaggggacccaggtcaccgtcgcctcg;

SEQ ID NO.19：DKTHTCP；

SEQ ID NO.20：

PCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK;

SEQ ID NO.21：

DVQLVESGGGLVEPGESLRLSCAAPGEDLGYYAIAWFRQAPGKEREVVSCVTSSGSSTNYLSSVKDRFTISIDNAKNTVYLQMNSLKPEDTAVYYCASTILLCSDYISAFGTWGQGTQVTVASGGGGSGGGGSGGGGSQVQLVESGGGLVQPGGSLRLSCAASGEKLDYFAIGWFRQAPGKEREVVSCVTSSGSSTNYLSSVKDRFTISIDNAKNTVYLQMNSLKPEDTAIYYCASTILLCSDYISAFGTWGQGTQVTVASDKTHTCPPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK;

SEQ ID NO.22：

gatgtgcagctggtggagtctgggggaggcttggtcgagcctggggaatctctgaggctctcctgtgcagcccctggagaggatttgggttattacgccatagcctggttccgccaggccccagggaaggagcgtgaggtagtctcatgtgtcacaagtagtggtagtagcacaaactatttaagttccgtgaaggaccgattcaccatctccatagacaacgccaagaacacggtatatctgcaaatgaacagcctgaaacctgaggacacagccgtttattactgtgcgtccactattctcctctgttcagattatatctctgcctttggcacctggggccaggggacccaggtcaccgtcgcctcgggaggcggaggatctggcggaggtggaagtggcggaggcggttctcaggtgcagctcgtggagtcggggggaggcttggtgcagcccgggggatctctgaggctctcgtgtgcagcctctggagagaaattggattattttgccataggctggttccgccaggccccagggaaggagcgtgaggtagtctcatgtgtcacaagtagtggtagtagcacaaactatttaagttccgtgaaggaccgattcaccatctccatagacaacgccaagaacacggtatatctgcaaatgaacagcctgaaacctgaggacacagccatttattactgtgcgtccactattctcctctgttcagattatatctctgcctttggcacctggggccaggggacccaggtcaccgtcgcctcggacaaaactcacacatgcccaccgtgcccagcacctgaactcctggggggaccgtcagtcttcctcttccccccaaaacccaaggacaccctcatgatctcccggacccctgaggtcacatgcgtggtggtggacgtgagccacgaagaccctgaggtcaagttcaactggtacgtggacggcgtggaggtgcataatgccaagacaaagccgcgggaggagcagtacaacagcacgtaccgtgtggtcagcgtcctcaccgtcctgcaccaggactggctgaatggcaaggagtacaagtgcaaggtctccaacaaagccctcccagcccccatcgagaaaaccatctccaaagccaaagggcagccccgagaaccacaggtgtacaccctgcccccatcccgggaggagatgaccaagaaccaggtcagcctgacctgcctggtcaaaggcttctatcccagcgacatcgccgtggagtgggagagcaatgggcagccggagaacaactacaagaccacgcctcccgtgctggactccgacggctccttcttcctctacagcaagctcaccgtggacaagagcaggtggcagcaggggaacgtcttctcatgctccgtgatgcacgaggctctgcacaaccactacacgcagaagagcctctccctgtctccgggtaaataa.

Preparation and purification of bivalent single domain antibodies (C3-G4):

And (I) carrying out gene synthesis on the bivalent single domain antibody sequence, and subcloning the bivalent single domain antibody sequence and the human IgG1Fc in series into an expression vector pcDNA3.4-hIgG1-Fc (IgG 1 constant region amino acid sequence SEQ ID NO. 26). After the vector is verified by sequencing, the Qiagen plasmid megapump kit is used for preparing the endotoxin-removing plasmid for standby.

And (II) taking the LVTransm transfection reagent and the single-chain antibody expression vector out of the refrigerator, thawing at room temperature, and blowing up and down by a pipetting gun to completely mix uniformly. The PBS buffer was removed and warmed to room temperature. Taking 2mL of PBS to one hole of a 6-hole plate, respectively adding 130 mug antibody expression vector, blowing up and down by a pipette, fully and uniformly mixing, adding 400 mug L LVTRANSM, immediately blowing up and down by the pipette, uniformly mixing, and standing for 10 minutes at room temperature.

(III) the DNA/LVTransm complex was added to 30mL of 293F cells, gently swirled and thoroughly mixed. After the cells were placed in a 37℃5% CO ₂ incubator at 130rpm for 6-8 hours, 50mL of fresh 293 cell medium was added and the cells were returned to the incubator for continued culture.

(IV) after 7 days of continuous culture, the culture supernatant was collected by centrifugation, filtered with a 0.45 μm filter membrane, and the filtrate was transferred to a sterile centrifuge tube and the antibody was purified using Protein A.

The purity of the antibody was >90%, and the SDS-PAGE results are shown in FIG. 1.

SEQ ID NO.26：

DKTHTCPPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSREEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK.

Example 2 affinity assay

2.1 Detection of ELISA binding Activity of Human IL-17A recombinant protein and control antibody

(1) The IL-17A recombinant protein was diluted with sterile CBS to a final concentration of 2. Mu.g/mL. A new 96-well plate was taken and 100. Mu.L/well coated overnight at 4 ℃.

(2) The antigen coating was removed and washed 3 times with PBST (0.5% tween).

(3) Blocking was performed at 37℃for 2 hours with the addition of 200. Mu.L/well of 3% MPBS;

(4) After removal of the blocking buffer, the well plate was washed 3 times with PBST;

(5) The positive control antibody Ixekizumab is diluted to 10 mug/ml by PBS, 7 points are diluted 5 times, 100 mug/well is added into an ELISA plate, and the incubation is carried out for 1 hour at room temperature, and the control well is PBS;

(6) Remove the liquid in the wells and wash 3 times with PBST;

(7) Adding secondary antibody HRP-ProteinA (Boster, BA 1080) for 1:10000 dilution, adding into enzyme label plate according to 100 mu L/hole, and incubating for 1 hour at room temperature;

(8) After removing the liquid from the wells, the well plate was washed 3 times with PBST;

(9) Adding 100 mu L/hole TMB color development liquid;

(10) Incubating for 15 minutes at room temperature in a dark place;

(11) Add 50. Mu.L/Kong Zhongzhi of liquid (2M HCl);

(12) OD450 values within wells were read using a microplate reader.

The results are shown in Table 1: the positive antibody is well combined with IL-17A antigen protein, and can be used for immunization.

TABLE 1 detection of binding Activity of human IL17A to Positive antibodies

2.2 Affinity detection methods and results

2.2.1HRP-STREPTAVDIN ELISA detection

Coating the purified single domain antibody 2ug/mL on a 96-well ELISA plate, adding Biotin-IL-17A-His, diluting 7 points with a 5-fold gradient with the initial concentration of 10ug/mL, and performing ELISA detection by using HRP-STREPTAVDIN. The detection result is EC 50=1.231 ug/mL of bivalent single domain antibody (C3-G4), EC 50=10.06 ug/mL of positive antibody (Ixekizumab), indicating that the bivalent single domain antibody (C3-G4) can bind to the target protein with higher binding capacity than the positive antibody (Ixekizumab), and the result is shown in fig. 2.

2.2.2ForteBio OCTET R2 Instrument for determining antibody affinity

(1) Antibody affinity determination using ForteBio OCTET R2 instrument, HIS1K sensor ProA Biosensors) solidified IL7A-His at a concentration of 5ug/mL. /(I)

(2) The buffer was PBST (PBS+0.02% tween 20), and the candidate antibody samples were diluted to 50nM,25nM,12.5nM,6.25nM,3.13nM,0nM.

(3) Affinity detection: equilibrium is carried out for 60s, binding for 180s, dissociation for 180s, and detection temperature is 25 ℃.

(4) Kinetic characterization analysis was performed using the ForteBio OCTET R2 system.

From the results, kd=1.391× ^-9 M of bivalent single domain antibody (C3-G4), kd= 3.910 × ^-10 M of positive antibody (Ixekizumab) (fig. 3).

Example 3 blocking function experiment

Adding gradient diluted detection antibody (positive antibody: ixekizumab; to-be-detected antibody: bivalent single domain antibody (C3-G4)) into a 96-well plate, diluting the antibody according to 10 times of gradient, continuously diluting 10 gradients, adding 50 mu L of diluted gradient concentration antibody into the 96-well plate according to the final concentration of 100μg/mL,10μg/mL,1μg/mL,0.1μg/mL,0.01μg/mL,0.001μg/mL,0.0001μg/mL,0.00001μg/mL,0.000001μg/mL,0.0000001μg/mL,0μg/mL,, and adding 2 multiple wells for each gradient. Then 50. Mu.L of IL-17A protein (0.4. Mu.g/mL final concentration) was added to the corresponding wells. After mixing, the mixture was placed in an incubator at 37℃and incubated for 1 hour. 293F-IL-17RA-IL-17Rc-ACT 1-NFkB-Luc cells cultured to the logarithmic growth phase were aspirated into 96-well plates, and 2X 10 ⁴ cells were seeded per well. After 18h of co-cultivation, 20. Mu.L of Bright-GloTM detection reagent was added to each well and the luciferase activity values in the wells were detected using a Tecan M1000pro microplate reader.

3.2 Results

As a result, it was found that the positive control Ixekizumab had an IC50 of 2.235nM and the bivalent single-domain antibody (C3-G4) had an IC50 of 1.192nM, both of which block the Human IL-17A protein from activating 293F-IL-17RA-IL-17Rc-ACT 1-NFkB-Luc, and the blocking effect of the bivalent single-domain antibody was significantly better than that of the positive control (FIG. 4).

Example 4 stability experiment

By detecting fluorescence change through a micro-differential scanning fluorescence technique (nanoDSF), thermal denaturation and chemical denaturation of the protein can be detected under natural conditions, and the temperature (T _m) when 50% of the protein is in an unfolded state and the temperature (T _agg) when aggregation begins to occur can be accurately determined; the higher the heat denaturation T _m、T_onset value and T _agg indicates the more stable the antibody protein.

4.1 Experimental procedure

Taking 100 mu L of candidate antibody prepared in the earlier stage and Ixekizumab (the concentration of a sample is greater than 200 mu g/mL), centrifuging at 4 ℃ and 12000 Xg for 10min, sucking the sample by using a capillary tube, preparing two capillaries for each sample, taking the capillaries as parallel control, putting the capillaries into corresponding clamping grooves in sequence, ensuring that the capillaries are full of the sample, and carrying out detection analysis.

4.2 Results

The stability results of the bivalent single domain antibody (C3-G4) and the positive control Ixekizumab are shown in FIGS. 5-6, and the results show that the T _m1 of the bivalent single domain antibody (C3-G4) is 62.20 ℃, the T _m3 is 81.58 ℃, the T _onset is 47.54 ℃, and the T _agg is 81.73 ℃; the positive control Ixekizumab had T _m1 of 56.10 ℃, T _m2 of 79.84 ℃, T _onset of 47.50 ℃, and T _agg of 61.86 ℃. The results show that the stability of the bivalent single domain antibody (C3-G4) is obviously higher than that of the positive control Ixekizumab.

Application example 1: pharmaceutical composition containing bivalent single-domain antibody (C3-G4)

A pharmaceutical composition comprising: (1) a buffer; and (2) a bivalent single domain antibody (C3-G4) or antigen-binding fragment thereof.

In some embodiments, the concentration of the bivalent single domain antibody (C3-G4) or antigen-binding fragment thereof is 1-300mg/L; preferably 5-100mg/L; more preferably 5-50mg/L.

In some embodiments, the buffer is selected from at least one of acetate buffer, histidine buffer phosphate buffer, citrate buffer, carbonate buffer, or Tris; preferably, the buffer is histidine buffer; more preferably, the histidine buffer is histidine-histidine hydrochloride buffer.

In some embodiments, the buffer is at a concentration of 3 to 60mM; preferably 5-20mM; the pH of the buffer is 4.0-7.0, preferably 5.0-6.0.

In some embodiments, the pharmaceutical composition further comprises a stabilizer selected from at least one of arginine salt, sodium chloride, mannitol, sorbitol, sucrose, glycine, and trehalose; preferably, the concentration of the stabilizing agent in the pharmaceutical composition is 50-400mM, preferably 100-200mM, more preferably 100-150mM.

In some embodiments, the stabilizer is sucrose, at a concentration of 100-300mM, preferably 150-200mM; or the stabilizer is a combination of sucrose and arginine hydrochloride, wherein the concentration of sucrose is 50-200mM, the concentration of arginine hydrochloride is 10-100mM, preferably, the concentration of sucrose is 100-150mM, and the concentration of arginine hydrochloride is 30-50mM.

In some embodiments, the pharmaceutical composition further comprises a surfactant selected from at least one of polysorbate 80, polysorbate 20, and poloxamer 188.

In some embodiments, the pharmaceutical composition further comprises an additional agent for treating an immune disorder or an anti-tumor agent.

Application example 2: drug conjugate containing bivalent single-domain antibody (C3-G4)

The invention provides a preparation method of a drug conjugate containing a bivalent single domain antibody (C3-G4), which comprises the following steps:

(1) Reacting a bivalent single domain antibody (C3-G4) or antigen-binding fragment thereof with a reducing agent in a buffer;

(2) Reacting the linker-payload with the thiol-bearing antibody or antigen-binding fragment thereof obtained in step (1);

in some embodiments, the amount ratio of reducing agent to substance of the antibody or antigen binding fragment thereof is from 1:1 to 5:1; preferably 1:1 to 4:1; further preferably 1:1 to 3:1; even more preferably 2:1 to 3:1.

In some embodiments, the reducing agent is selected from tris (2-carboxyethyl) phosphine (TCEP) or a salt thereof, dithiothreitol, or 2-mercaptoethanol. In some embodiments the reducing agent is tris (2-carboxyethyl) phosphine or a salt thereof, preferably tris (2-carboxyethyl) phosphine hydrochloride (tcep·hcl).

In some embodiments, the buffer is selected from HEPES (4- (2-hydroxyethyl) -1-piperazine ethanesulfonic acid) buffer, histidine buffer, phosphate buffer, borate buffer, or acetate buffer; preferably histidine buffer; further preferred is histidine-hydrochloric acid buffer; the concentration of the buffer is 1mM-30mM, such as 5mM, 10mM, 15mM, 20mM, 25mM or 30mM, preferably 20mM.

In some embodiments, the ratio of the amount of linker-payload to the amount of substance of the antibody or antigen binding fragment thereof is from 2:1 to 10:1; preferably, the ratio of the amount of linker-payload to the amount of substance of the antibody or antigen binding fragment thereof is from 3:1 to 9:1; further preferred, the ratio of the amount of linker-payload to the amount of substance of the antibody or antigen binding fragment thereof is 4:1 to 7:1; further preferably, the ratio of the amount of linker-payload to the amount of substance of the antibody or antigen binding fragment thereof is from 5:1 to 7:1.

In some embodiments, a solvent for dissolving the linker-payload is also included; the solvent comprises an organic solvent; the organic solvent may be selected from aqueous acetone (e.g., 50% aqueous acetone), aqueous ethanol (e.g., 80% aqueous ethanol), aqueous methanol (e.g., 80% aqueous methanol), aqueous isopropanol (e.g., 80% aqueous isopropanol), aqueous dimethyl sulfoxide (e.g., 80% aqueous dimethyl sulfoxide), acetone, dimethyl sulfoxide (DMSO), dimethylformamide (DMF), dimethylacetamide (DMA), or N-methyl-2-pyrrolidone (NMP); preferably an aqueous acetone or DMSO, preferably 50% aqueous acetone.

Application example 3: kit for detecting IL-17A

The kit comprises the following components:

(1) Solid phase carriers (immunoadsorbents) coated with antigen or antibody;

(2) An enzyme-labeled antigen or antibody (conjugate);

(3) A substrate for an enzyme;

(4) Negative and positive controls (in qualitative assays), reference standards and control serum (in quantitative assays);

(5) A conjugate and a dilution of the specimen;

(6) Washing solution, in plate ELISA, common diluent containing 0.05% Tween-20 phosphate buffer saline;

(7) The enzyme reaction stopping solution, commonly used HRP reaction stopping solution is sulfuric acid, the concentration of which varies according to the addition amount and the final volume of the colorimetric solution, and 2mol/L is generally adopted in plate ELISA.

In some embodiments, the coating concentration is 0.3-5 μg/mL; preferably, the coating concentration is 2-3 mug/mL.

In some embodiments, the enzyme is selected from one of horseradish peroxidase, alkaline phosphatase, glucose oxidase, or β -galactosidase; preferably horseradish peroxidase; the substrate is selected from one of o-phenylenediamine, tetramethyl benzidine or aminosalicylic acid; tetramethyl benzidine is preferred.

Claims

1. An antibody comprising the following (a) and (b):

2. The antibody of claim 1, wherein the amino acid sequence of the antibody comprises an amino acid sequence obtained by at least one of addition, deletion, modification or substitution of the amino acid sequence set forth in SEQ ID nos. 1-6.

3. The antibody of claim 2, wherein the amino acid sequence of the antibody comprises an amino acid sequence having a1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16 amino acid difference compared to the amino acid sequence set forth in SEQ ID No. 1-6.

4. The antibody of any one of claims 1-3, wherein the first single domain antibody or the second single domain antibody further comprises at least 4 heavy chain framework regions for linking heavy chain variable regions.

5. The antibody of claim 4, wherein the heavy chain framework region comprises a portion or all of an antibody heavy chain framework region selected from human, murine, primate, or camelid sources or a variant thereof;

more preferably, the heavy chain framework regions of the antibodies or variants thereof are comprised in part or in whole selected from alpaca sources.

6. An antibody comprising the following (a) and (b):

FR1-HCDR1-FR2-HCDR2-FR3-HCDR3-FR4；

FR5-HCDR4-FR6-HCDR5-FR7-HCDR6-FR8；

the amino acid sequences of the HCDR1, the HCDR2 and the HCDR3 are selected from sequences shown in SEQ ID NO.1-3 or having 1,2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 or 16 amino acid differences compared with SEQ ID NO. 1-3;

the amino acid difference is realized by at least one mode of adding, deleting, modifying and/or substituting on the sequences shown in SEQ ID NO.1-3 and SEQ ID NO. 4-6.

7. The antibody of claim 6, wherein the HCDR1 has an amino acid sequence of SEQ ID No.1; the amino acid sequence of the HCDR2 is SEQ ID NO.2; the amino acid sequence of the HCDR3 is SEQ ID NO.3; the amino acid sequence of the HCDR4 is SEQ ID NO.4; the amino acid sequence of the HCDR5 is SEQ ID NO.5; the amino acid sequence of the HCDR6 is SEQ ID NO.6.

8. The antibody of any one of claims 1-7, wherein the amino acid sequences of the first single domain antibody and the second single domain antibody are directly linked or indirectly linked via a linker.

9. The antibody of claim 8, wherein the linker is (GGGGS) n, wherein n is selected from 1, 2, 3, 4, 5 or 6; preferably, the linker is (GGGGS) 3.

10. The antibody of any one of claims 1-9, wherein the sequence of attachment of the antibody is selected from one of the following (a) - (c):

11. The antibody of any one of claims 1-10, wherein the antibody is an anti-IL-17A antibody.

12. A recombinant protein comprising the antibody of any one of claims 1-11.

13. The recombinant protein according to claim 12, wherein said recombinant protein further comprises a biologically active protein or functional fragment thereof that aids in its expression and/or secretion, or that extends its half-life in vivo.

14. The recombinant protein according to claim 13, wherein said biologically active polypeptide or functional fragment thereof is selected from at least one of an immunoglobulin Fc domain, serum albumin, albumin binding polypeptide, prealbumin, carboxy terminal peptide, elastin-like polypeptide, his tag, GST tag, MBP tag, FLAG tag, and SUMO tag.

15. The recombinant protein according to claim 14, wherein said Fc domain is derived from a human, murine, primate or camelid antibody, or a variant thereof;

16. An antibody preparation comprising (a) and (b), wherein (a) and (b) are:

(a) The antibody of any one of claims 1-11 or the recombinant protein of any one of claims 12-15;

(b) A pharmaceutically acceptable carrier.

17. A kit comprising the antibody of any one of claims 1-11 or the recombinant protein of any one of claims 12-15 or the antibody preparation of claim 16;

Preferably, the kit further comprises a container for loading the antibody preparation.

18. A drug conjugate comprising (a) and (b), wherein (a) and (b) are:

(b) A coupling moiety coupled to (a).

19. An isolated nucleic acid molecule encoding the antibody of any one of claims 1-11 or the recombinant protein of any one of claims 12-15.

20. An expression vector comprising the nucleic acid molecule of claim 19.

21. A pharmaceutical composition comprising the antibody of any one of claims 1-11 or the recombinant protein of any one of claims 12-15 or the antibody preparation of claim 16 or the drug conjugate of claim 18 or the nucleic acid molecule of claim 19 or the expression vector of claim 20;

Preferably, the pharmaceutical composition further comprises at least one pharmaceutically acceptable excipient.

22. The antibody of any one of claims 1-11 or the recombinant protein of any one of claims 12-15 or the antibody preparation of claim 16 or the drug conjugate of claim 18 or the pharmaceutical composition of claim 21 for at least one of the following uses (a) - (c):

(a) Preparing a detection reagent or a kit;

(b) Preparing a medicament for preventing and/or treating autoimmune diseases;

(c) Preparing medicine for preventing and/or treating cancer.

23. The use according to claim 22, characterized in that, the autoimmune diseases include Behcet's disease, systemic lupus erythematosus, chronic discoid lupus erythematosus, multiple sclerosis, systemic scleroderma, progressive systemic sclerosis, scleroderma, polymyositis, dermatomyositis, perinodular arteritis, aortitis syndrome, malignant rheumatoid arthritis, juvenile idiopathic arthritis, spondyloarthritis, mixed connective tissue disease, kaschmann's disease, sjogren's syndrome, adult Steve's disease, vasculitis, allergic granulomatous vasculitis, allergic vasculitis, rheumatoid vasculitis, macrovasculitis, ANCA-related vasculitis, cogan's syndrome, RS3PE syndrome, temporal arteritis, polymyalgia rheumatica, antiphospholipid antibody syndrome, eosinophilic fasciitis, igG 4-related diseases, guillain Barre syndrome myasthenia gravis, chronic atrophic gastritis, autoimmune hepatitis, nonalcoholic steatohepatitis, primary biliary cirrhosis, good-pasture syndrome, acute glomerulonephritis, lupus nephritis, megaloblastic anemia, autoimmune hemolytic anemia, pernicious anemia, autoimmune neutropenia, idiopathic thrombocytopenic purpura, bazedol's disease, hashimoto's disease autoimmune hypothyroidism, primary hypothyroidism, addison's disease, idiopathic Addison's disease, type I diabetes, slowly progressive type I diabetes, focal scleroderma, psoriasis and psoriatic arthritis, bullous pemphigoid, gestational herpes, linear IgA bullous dermatoses, acquired bullous epidermolysis bullosa, alopecia areata, leukoplakia, vitiligo vulgaris, neuromyelitis optica, chronic inflammatory demyelinating polyneuropathy, multifocal motor neuropathy, sarcoidosis, giant cell arteritis, amyotrophic lateral sclerosis, former field disease, autoimmune optic neuropathy, idiopathic azoospermia, habitual abortion, inflammatory bowel disease, celiac disease, ankylosing spondylitis, severe asthma, chronic urticaria, familial mediterranean fever, eosinophilic chronic sinusitis, dilated cardiomyopathy, systemic mastocytosis or inclusion body myositis;

Preferably, the autoimmune disease is plaque psoriasis, rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis or lupus nephritis.

24. The use according to claim 22 or 23, wherein the cancer comprises basal cell carcinoma, cholangiocarcinoma, bladder cancer, bone cancer, breast cancer, peritoneal cancer, cervical cancer, cholangiocarcinoma, choriocarcinoma, colorectal cancer, connective tissue cancer, digestive system cancer, endometrial cancer, esophageal cancer, eye cancer, head and neck cancer, gastric cancer, glioblastoma, liver cancer, kidney cancer, laryngeal cancer, leukemia, liver cancer, lung cancer, lymphoma, melanoma, myeloma, neuroblastoma, oral cancer, ovarian cancer, pancreatic cancer, prostate cancer, retinoblastoma, rhabdomyosarcoma, rectal cancer, respiratory cancer, salivary gland cancer, sarcoma, skin cancer, squamous cell carcinoma, testicular cancer, thyroid cancer, uterine cancer, urinary system cancer, B-cell lymphoma, chronic lymphocytic leukemia, acute lymphoblastic leukemia, hairy cell leukemia or chronic myelogenous leukemia.

25. A method for in vitro detection of IL-17A in a sample for non-diagnostic purposes, said method comprising the steps of:

s1, the antibody of any one of claims 1-11 or the recombinant protein of any one of claims 12-15 or the antibody preparation of claim 16 or the drug conjugate of claim 18, is contacted with a sample to be tested;

s2, detecting an antigen-antibody complex;

S3, judging a result.

26. A method of preventing and/or treating an autoimmune disease, comprising administering to a subject in need thereof a therapeutically effective amount of the antibody of any one of claims 1-11 or the recombinant protein of any one of claims 12-15 or the antibody preparation of claim 16 or the drug conjugate of claim 18.

27. A method of preventing and/or treating cancer, comprising administering to a subject in need thereof a therapeutically effective amount of the antibody of any one of claims 1-11 or the recombinant protein of any one of claims 12-15 or the antibody preparation of claim 16 or the drug conjugate of claim 18.