KR20150131646A - Method for production antibodies to sucrase-isomaltase - Google Patents

Abstract

The present invention relates to a novel method for producing antibodies against sucrase-isomaltase and to antibodies against sucrase-iso-maltase produced thereby. In addition, the present invention relates to a kit for diagnosing one or more of diabetes, obesity and digestive disorders comprising antibodies against sucrase-isomaltase. The present invention also relates to a pharmaceutical composition for treating or preventing one or more of diabetes, obesity and digestive disorders comprising an antibody against sucrase-isomaltase as an active ingredient.
According to the method of the present invention, a monoclonal antibody or a polyclonal antibody can be selected according to the purpose of the present invention. Also, the antibody can be prepared as an antibody for various research purposes, such as Western blotting, ELISA kit, Can be used.

Description

METHOD FOR PRODUCTION ANTIBODIES TO SUCRASE-ISOMALTASE BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

The present invention relates to a novel method for producing antibodies against sucrase-isomaltase and to antibodies against sucrase-iso-maltase produced thereby. In addition, the present invention relates to a kit for diagnosing one or more of diabetes, obesity and digestive disorders comprising antibodies against sucrase-isomaltase. The present invention also relates to a pharmaceutical composition for treating or preventing one or more of diabetes, obesity and digestive disorders comprising an antibody against sucrase-isomaltase as an active ingredient.

Due to the rapid increase in diabetic patients and obesity population, research and development in related fields are actively under way. In addition, the elderly population accounts for an increasing proportion of the population as a result of aging, and an aging society is rapidly emerging. As a result, interest in diabetic and obesity as well as functional digestive disorders of the elderly is greatly increasing.

Obesity is a major cause of heart disease, cancer, hypertension, diabetes, and degenerative arthritis. If the current obesity trend is on the rise, one-third of the world's population will become obese (body mass index 30 kg / m ² ). In Korea, the obesity population with a body mass index of more than 25 kg / m ² reached 30.7% in 2008, and the proportion of highly obese people with a body mass index of more than 30 kg / m ² increased from 2.3% in 1998 to 4.1% Respectively.

Currently, the global anti-obesity material market is over $ 200 billion, and it is expected to grow rapidly every year due to the increase in the obesity population. However, various side effects such as 'orlistat', 'sibutramine' and 'sertraline', which are currently used in the present anti-obesity drugs, have been reported. .

Therefore, the promotion and inhibition of expression of intestinal digestive enzymes, which are essential for diabetes, obesity and digestive disorders, are the main research topics.

On the other hand, Sucrase-Isomaltase (SI complex) is a glucosidase enzyme having the system name of oligosaccharide 6-alpha-glucohydrolase. Most of the SI complex antibodies are produced and sold in the form of polyclonal antibodies from Santa Cruz Biotechnology, USA.

Rat-derived sucrase-isomaltase digesting enzyme is a complex consisting of 1012 amino acid iso-maltase and 828 amino acid sucrose with a polar covalent bond.

Korean Patent Registration No. 10-0435829 discloses a method for producing an egg yolk antibody against sucrase and maltase, and a composition for inhibiting the absorption of a dietary carbohydrate using the same, wherein the egg yolk antibody inhibits the degradation of carbohydrate It is disclosed that it can be effectively used for prevention and treatment of diet materials and diabetes for improving obesity without restriction of food intake.

In the present invention, it is an object of the present invention to easily produce an anti-SI complex antibody necessary for the study of diabetes, obesity, digestive disorders, etc., and to provide an antibody for various types of studies.

As a result, the present inventors have newly discovered a method for producing an antibody against sucrase-iso-maltase by using sucrose in which a specific site of amino acid is removed as an immunogen, The present invention has been completed.

According to the method of the present invention, a monoclonal antibody or a polyclonal antibody can be selected according to the purpose of the study, and antibodies for various research purposes such as Western blotting, an ELISA kit, and a column can be produced.

1 is a schematic diagram showing an example of a method for producing a sample for vector transformation and protein quantification.
FIG. 2 is a view showing a whole sucrase-iso-maltase complex and a sucrase moiety to be expressed using E. coli.
Figure 3 shows a modified sucrase DNA sequence for E. coli expression.
Figure 4 shows the amino acid sequence of rat sucrase.
5 is a schematic diagram showing an example of a method for constructing a recombinant expression vector (pET22-6HrSucD120).
Fig. 6 is an analysis of the expression of the transformant BL21 (DE3) / pET22-6HrSucD120.
Fig. 7 shows the expression of the transformant Rosetta-gami (DE3) / pET22-6HrSucD120.
FIG. 8 shows the result of SDS-PAGE analysis of the washing step using 2 M urea.
FIG. 9 shows the result of SDS-PAGE analysis of the washing step using 4 M urea.
Fig. 10 shows the result of SDS-PAGE analysis of the denaturation step using 8 M urea.
Figure 11 shows the chromatogram (A) and SDS-PAGE analysis (B) of polyhistidine tagged sucrase (120 amino acid removal) purified by IMAC.
12 is a schematic view showing an example of a sucrose refolding process.
Figure 13 compares the formation of insoluble aggregates of polyhistidine tagged sucrase according to the number of amino acid deletions (60 amino acids and 120 amino acids) using the same refold buffer.
Fig. 14 shows the results of SDS-PAGE analysis of polyhistidine tagged sucrase (120 amino acid removal) after refolding.
15 shows the result of SDS-PAGE analysis of polyhistidine-tagged sucrase (120 amino acid removal) after ultrafiltration.
16 is a graph showing the results of ELISA assays according to primary antigen immunity of sucrase.
17 is a graph showing the results of ELISA assays according to secondary antigen immunity of sucrase.
18 is a graph showing the results of comparing antibody production ability according to immunity frequency.
19 is a graph showing the number of anti-sucrase monoclonal antibody clones.
FIG. 20 is a graph showing ELISA test by diluting 63 clones of the monoclonal antibody. FIG.
Figure 21 shows the result of western blotting using rat intestinal acetone powder (protein concentration = 10 / / ml).

Hereinafter, the present invention will be described in detail. However, it should be understood that the present invention may be embodied in many other specific forms without departing from the spirit or essential characteristics thereof.

In one aspect, the present invention relates to a novel method of producing an antibody (anti-SI complex antibody) against Sucrase-Isomaltase (SI complex), a recombinant expression vector used in the method, Lt; RTI ID = 0.0 > ss-isomaltase. ≪ / RTI >

Specifically, the present invention relates to a method for producing an antibody against sucrase-isomaltase, characterized in that 120 amino acid-deleted sucrase is used as an immunogen.

In a preferred embodiment, the present invention utilizes sucrose with 120 amino acids at the N-terminus as an immunogen.

In a more preferred embodiment, the method for producing an antibody of the present invention comprises the step of removing 120 amino acids at the N-terminus and preparing a sucracase expression vector into which a polyhistidine tag is introduced.

As an example, the present invention includes a step of producing a sucrase expression vector in which 120 amino acids are removed at the N-terminus and six histidine purification tags are introduced. Specifically, the vector of the present invention is designed so as to remove 120 amino acids from the N-terminus and introduce six histidine tags to connect the 121st amino acid from the N-terminus of sucrase.

Accordingly, the present invention relates to a recombinant expression vector comprising a sucrose sequence in which 120 amino acids are removed at the N-terminus and 6 histidine purification tags are introduced, a method for producing the recombinant expression vector, and a transformant into which the vector is introduced.

Escherichia coli is most widely used as a host cell for expression and production of foreign proteins because of its high growth rate, easy cultivation and well-known genetic characteristics. However, when a small peptide such as a hormone is directly expressed in Escherichia coli, most peptides expressed by the protease are degraded in the cell, and when the protein to be produced is too large, the expression itself does not work well. Therefore, E. coli has a small peptide, And has a fatal disadvantage as a host cell for the expression of large proteins. Therefore, in order to solve such a problem, in the present invention, only 828 Saccharose parts in the whole complex are expressed in E. coli.

A preferred example of an expression vector of the present invention is shown in Fig.

The antibody produced in the present invention may be a monoclonal antibody, a polyclonal antibody, a humanized antibody, a bispecific antibody or a heterozygous antibody. The method of producing the antibody is not particularly limited, and it is possible to manufacture according to a method of manufacturing an antibody which is already known or will be known in the future. Representative methods of antibody production are described below.

The polyclonal antibody is preferably generated in an animal by subcutaneous or intraperitoneal injection of an antigen and an adjuvant several times. It may be useful to conjugate the relevant antigen (especially when a synthetic peptide is used) to a protein that exhibits immunogenicity in the species to be immunized.

For example, soybean trypsin inhibitors using keyhole limpet hemocyanin (KLH), serum albumin, sorbitol globulin, or bifunctional or derivatizing agents such as maleimido benzoyl sulfosuccinimide ester (see, for example, (Bonded through a cysteine residue), N-hydroxysuccinimide (conjugated via a lysine residue), glutaraldehyde, succinic anhydride, SOCl2 or R1N = C = NR where R and R1 are different alkyl groups The relevant antigen can be conjugated.

For example, 100 μg or 5 μg of protein or conjugate (which is the dose for each rabbit or mouse, respectively) is combined with a 3-fold volume of Freund's complete adjuvant, , Immunogenic conjugates or derivatives. One month later, further inoculation to the animal is carried out by subcutaneously injecting the peptide or conjugate contained in the Freund's complete adjuvant at several sites at 1/5 to 1/10 the original volume. After 7 to 14 days, the animal is sampled and the antibody titer of the serum is analyzed. The animals are given additional booster until the titer is reached. The conjugate can also be produced as a protein fusion in a recombinant cell culture. In addition, flocculants such as alum are suitably used to increase the immune response.

A monoclonal antibody refers to a highly specific antibody presented against a single antigenic site (epitope). Unlike polyclonal antibodies, which typically contain different antibodies presented against different epitopes, monoclonal antibodies are presented for a single epitope on the antigen. Monoclonal antibodies have the advantage of improving the selectivity and specificity of diagnostic and analytical assays that utilize antigen-antibody binding and are also produced by incubation of hybridomas, and thus are not contaminated by other immunoglobulins .

Monoclonal antibodies may be prepared using the hybridoma method first described in Kohler et al., Or by recombinant DNA methods (US Patent No. 4,816,567). In the hybridoma method, a mouse or other appropriate host animal (e. G., A hamster) is immunized as described above to induce a lymphocyte capable of producing or producing an antibody that will specifically bind to the protein used for immunization . In a different way, the lymphocytes may be in vitro immunized. After immunization, the lymphocytes are isolated and hybridoma cells are formed by fusion with myeloma cell lines using a suitable fusion agent (e. G., Polyethylene glycol) (Goding, Monoclonal Antibodies: Principles and Practice, pp. 59-103 (Academic Press, 1986)).

The hybridoma cells thus prepared are preferably grown by inoculation into a suitable culture medium containing one or more substances that inhibit the growth or survival of non-fused unmyelinated cell (fusion partner). For example, in the absence of hypoxanthine guanine phospholibosyl transferase (HGPRT or HPRT) enzyme in a cell of a myeloma, the hybridoma selective culture medium usually contains hypoxanthine, a substance that inhibits the growth of HGPRT-deficient cells, Aminopterin and thymidine (HAT medium). A preferred fusion partner, myeloma cells, is a cell that efficiently fuses and supports stable high-level production of antibody by the selected antibody-producing cells, and is sensitive to the selection medium that selects the myeloma cells from unfused mother cells Do. Preferred myeloma cell lines are derived from murine myeloma cell lines such as MOPC-21 and MPC-11 mouse tumors (available from the Salk Institute Cell Distribution Center), and SP-2 and derivatives (e.g., X63-Ag8-653 cells Available from the American Type Culture Collection. Human myeloma and mouse-human xenogeneic myeloma cell lines for the production of human monoclonal antibodies are also described in Kozbor, J. Immunol., 133: 3001 (1984), Brodeur et al., Monoclonal Antibody Production Techniques and Applications, pp. 51-63 (1987).

The culture medium in which the hybridoma cells are growing is analyzed for the production of the monoclonal antibodies presented for the antigen. Preferably, the binding specificity of the monoclonal antibody produced by the hybridoma cells is determined by immunoprecipitation or in vitro binding assay, for example, radioimmunoassay (RIA) or enzyme linked immunosorbent assay (ELISA) do. The binding affinity of monoclonal antibodies is described, for example, in Munson et al., Anal. Biochem., 107: 220 (1980).

Once the hybridoma cells are found to produce antibodies with the desired specificity, affinity and / or activity, the clones can be subcloned by a limiting dilution procedure and grown by standard methods (Goding, Monoclonal Antibodies: Principles and Practice, pp. 59-103 (Academic Press, 1986)). Suitable culture media for this purpose include, for example, D-MEM or RPMI-1640 medium. Hybridoma cells can also be grown in vivo as multiple tumors in animals by, for example, intraperitoneal injection of hybridoma cells into mice. The monoclonal antibody secreted by the subclone may be purified using conventional antibody purification procedures, such as affinity chromatography (using, for example, protein A-sepharose or protein G-sepharose), ion exchange chromatography It is suitable to separate from the culture medium, plural liquids or serum by means of electrophoresis, hydrolysis, proteolysis, gel electrophoresis, dialysis or the like.

The DNA encoding the monoclonal antibody can be readily isolated using conventional procedures (e.g., using an oligonucleotide probe capable of specifically binding to the heavy and light chain genes of the murine antibody) Analyze. Hybridoma cells function as a desirable source of such DNA. After isolation, the DNA may be located in an expression vector, which is then transformed into host cells such as E. coli cells, monkey COS cells, Chinese hamster ovary (CHO) cells, or myeloma cells that do not otherwise produce antibody proteins And the monoclonal antibody can be synthesized from this recombinant host cell. For review of recombinant expression of the DNA encoding the antibody in bacteria, see Skerra et al., Curr. Opinion in Immunol., 5: 256-262 (1993), Plueckthun, Immunol. Revs., 130: 151-188 (1992).

DNA encoding the antibody can be obtained, for example, by substituting the constant domain (CH and CL) sequences of human heavy and light chains in place of homologous murine sequences (U.S. Patent No. 4,816,567, Morrison et al., Proc. Natl. Acad ), A chimeric or fusion antibody polypeptide is generated by fusing immunoglobulin coding sequences with all or a portion of the coding sequence for a non-immunoglobulin polypeptide (heterologous polypeptide) . It is also possible to replace the constant domains of the antibody by such non-immunoglobulin polypeptide sequences or by replacing the variable domains of one antigen-binding site of the antibody with these polypeptides, so that one antigen-binding site exhibiting specificity for the antigen, Lt; RTI ID = 0.0 > anti-chimeric < / RTI >

In addition, the anti-SI complex antibody of the present invention may comprise a humanized antibody or a human antibody. Humanized forms of non-human (e.g., murine) antibodies include chimeric immunoglobulins, immunoglobulin chains, or fragments thereof (e. G., Fv, Fab, Fab ') containing a minimal sequence derived from a non-human immunoglobulin. , F (ab ') 2 or other antigen-binding subsequences of the antibody). Humanized antibodies are human immunogens that replace a residue from the complementarity determining region (CDR) of a recipient with a residue from a CDR of a non-human species (donor antibody) such as a mouse, rat or rabbit having the desired specificity, affinity and ability Globulin (accepting antibody). In some cases, the Fv framework residues of the human immunoglobulin are replaced with corresponding non-human residues. In addition, the humanized antibody may include residues that are not found in the acceptor antibody and are not found in the introduced CDR or framework sequences. In general, a humanized antibody will comprise substantially all of one or more, typically two or more, variable domains, wherein all or substantially all of the CDR regions correspond to regions of non-human immunoglobulin, and all or substantially all All FR regions correspond to regions of the human immunoglobulin common sequence. In addition, the humanized antibody will most preferably comprise at least a portion of an immunoglobulin constant region (Fc), typically at least a portion of a human immunoglobulin region (Jones et al., Nature, 321: 522-525 (1986) , Riechmann et al., Nature, 332: 323-329 (1988), Presta, Curr., Op. Struct Biol., 2: 593-596 (1992), etc.).

Methods for humanizing non-human antibodies are known in the art. In general, humanized antibodies are introduced with one or more amino acid residues derived from non-human sources. These non-human amino acid residues are often referred to as "import" residues, and are typically obtained from the "import" Humanization is essentially the same as that described by Winter et al., Nature, 321: 522-525 (1986), Riechmann et al., Nature, 332: 323 -327 (1988), Verhoeyen et al., Science, 239: 1534-1536 (1988), etc.). Thus, such "humanized" antibodies are chimeric antibodies (U.S. Patent No. 4,816,567) in which substantially fewer sequences are replaced by the corresponding sequences from non-human species than the intact human variable domain. Indeed, humanized antibodies are typically human antibodies in which some CDR residues and possibly some FR residues have been replaced with residues from similar regions of the rodent antibody.

In another aspect, the present invention relates to a kit for diagnosing one or more of diabetes, obesity, and digestive disorders comprising antibodies to the sucrase-isomaltase.

In another aspect, the present invention relates to a pharmaceutical composition for the treatment or prevention of one or more of diabetes, obesity and digestive disorders comprising an antibody against sucrase-isomaltase as an active ingredient.

The pharmaceutical composition according to the present invention may be formulated into oral compositions such as powders, granules, tablets, capsules, suspensions, emulsions, syrups and aerosols, external preparations, suppository sterilized injection solutions, pre-filled syringe solution, or a lyophilized form, but the present invention is not limited thereto.

In the case of formulation, it may be prepared using diluents or excipients such as fillers, extenders, binders, humectants, disintegrants, surfactants and the like which are usually used. Solid formulations for oral administration include tablets, pills, powders, granules, capsules and the like, which may contain at least one or more excipients such as starch, calcium carbonate, sucrose, lactose, gelatin, . In addition to simple excipients, lubricants such as magnesium stearate and talc may also be used.

Liquid preparations for oral administration include suspensions, solutions, emulsions, syrups, and the like. Various excipients such as wetting agents, sweetening agents, fragrances, preservatives and the like are included in addition to water and liquid paraffin which are conventionally used simple diluents . Formulations for parenteral administration include sterile aqueous solutions, non-aqueous solvents, suspensions, emulsions, freeze-dried preparations, suppositories, and the like.

The preferred dosage of the pharmaceutical composition of the present invention can be appropriately selected depending on the condition and body weight of the patient, the degree of symptoms, the type of disease, the drug form, the administration route and the period. It is preferable for the composition of the present invention to allow the active ingredient to be administered at 0.2 to 200 mg / kg per day for optimal efficacy. The administration may be carried out once a day or divided into several doses, but is not limited thereto.

The pharmaceutical composition of the present invention can be used for the prevention or treatment of one or more of diabetes, obesity and digestive disorders. In addition, the pharmaceutical composition of the present invention can be used for prevention or treatment of obesity-related or metabolic diseases caused by obesity. The metabolic diseases may be, but are not limited to, one or more diseases selected from the group consisting of hyperlipidemia, fatty liver, arteriosclerosis, cardiovascular disease, or metabolic syndrome in which the diseases occur simultaneously.

The present invention will be described in more detail with reference to the following examples. However, the following examples are for the purpose of illustrating the present invention and are not intended to limit the scope of the present invention.

[ Example ]

I. Antigen Production

1. Preparation and method of experiment

Use strains, plasmids and reagents

Escherichia coli used for protein production coli ) strain was BL21 (DE3) ( F- ompT hsdS _B ( r _B - m _B -) gal dcm ( DE3 ) (Novagen) and Rosetta- gami (DE3)) ((ara-leu) 7697 lacX74 phoA PvuII phoR araD139 ahpC galE galK rpsL (DE3) F'lac ⁺ lacl ^q progor522 :: Tn 10 trxB pRARE (Cam ^R , Kan ^R , Str ^R , Tet ^R ).

Further, Common DNA manipulation and E. coli strain used for plasmid isolation DH5a (F- F80dlacZM15 (_ lacZYA argF) U169 end A1 recA1 hsdR17 (rK - mK +) deoR thi _1 supE44 - gyrA96 relA1 ).

PET22b (Novagen) was used as a plasmid for expressing E. coli. A protein standard size marker for protein identification was obtained from Elpys, and a Bradford reagent for protein concentration was purchased from Bio-Rad.

Medium and culture conditions

The plasmids inserted into pET22b plasmid were transformed into Escherichia coli BL21 (DE3), and the transformant was transformed into ampicillin at a concentration of 50 μg / ml. Lt; RTI ID = 0.0 > LB < / RTI > The cultured cells were inoculated in a 10 ml LB liquid medium containing 50 μg / ml of ampicillin, cultured in a 37 ° C. shaking incubator for about 14 hours, and then again in a 1 L baffle flask in 250 ml LB medium TB medium, incubated up to 0.6 OD, added with IPTG (Isopropyl-BD-thiogalactopyranoside) to a final concentration of 1 mM, and then cultured up to 3 to 2 OD at 37 ° C or 25 ° C, Lt; / RTI > protein was allowed to express. After the incubation, the culture was centrifuged at 5,000 rpm for 5 minutes to collect the cells. The composition of the used LB medium and TB medium is shown in Table 1 below.

Restriction enzymes and reagents

Restriction enzymes for DNA recombination, T4 DNA ligase and PCR reagents (taq DNA polymerase, dNTP, etc.) were purchased from Boehringer Mannheim or Takara, and the medium was purchased from Difco. Other reagents related to electrophoresis were from Sigma, and the reagents related to the general proteins were obtained from Duchefa Biochemie.

Construction and Transformation of Recombinant Plasmids

Common DNA recombination techniques were performed by Maniatis et al. And Ausubel et al., And E. coli transformation was performed using CaCl ₂ Method.

Polymerase chain reaction PCR )

The rat sucrase gene, which was used as a template for PCR, was converted into a DNA codon that was well expressed in Escherichia coli and was synthesized by Genentech.

The primers used in this example were synthesized using a DNA synthesizer (Perseptive Biosystems, Model 8909).

The PCR was carried out by adding 10 μl of 10 × polymerase buffer, 8 μl of 10 × dNTP solution (final 0.2 mM), 1 μl of two primers (100 pmoles each), 3 μl of template DNA solution and 75 μl of DNA was denatured at 95 ° C for 5 minutes in a PCR machine (Perkinelmer, Model GeneAmp PCR system 2400), followed by 30 cycles of PCR Respectively. The denaturation temperature and time were 1 min at 95 ° C, annealing at 55 ° C for 1 min, and extension at 72 ° C for 2 min. The PCR compositions (A) and (B) are shown in Table 2 below.

Protein quantification and SDS - PAGE

As shown in FIG. 1, plasmids inserted into pET22b were transformed into Escherichia coli, respectively, and induced to express IPTG in the culture medium. After incubation, the culture broth was centrifuged at 5,000 rpm for 5 minutes to recover the microbial cells. Ultrasonic destruction (Branson Sonifier 450, 3 KHz, 3 watts, 5 min) , And the expression was confirmed by dividing into a soluble fraction and an insoluble fraction by centrifugation. The separated microorganism was divided into a total fraction, an insoluble fraction and a soluble fraction and was dissolved in a protein lysis buffer (12 mM Tris-Cl, pH 6.8, 5% glycerol, 2.88 mM mercaptoethanol, 0.4% SDS, 0.02% And incubated for 5 minutes at 100 ° C. Each 20 μl of the resulting solution was transferred to a 5% storage gel on a 1 mm thick 10% separating gel (pH 8.8, 20 cm, 10 cm) pH 6.8, width 10 cm, length 12.0 cm), electrophoresed at 100-300 volts, 25 mA for 1 hour, and stained with Coomassie staining solution. Quantification of the proteins used in the whole process followed the Bradford method.

Fixed metal affinity chromatography ( IMAC )

Sukraase, which was expressed in the state that 6 histidine was introduced for purification in E. coli, recovered the cells through centrifugation from the Escherichia coli culture broth. The cells were washed with 50 mM Tris-HCl (pH 8.0) buffer, and the cells suspended in the same buffer were disrupted by sonication (Branson Sonifier 450, 3 KHz, 3 watts, 30 min) A marine fraction (inclusion body) was obtained. The ineffective fractions were sonicated (Branson Sonifier 450, 3 KHz, 3 watts, 30 min) in a buffer of 2 M urea, 500 mM NaCl and 50 mM Tris-HCl After that, the insoluble fraction and the insoluble fraction were separated by centrifugation to recover the insoluble fraction. The insoluble fractions were solubilized by ultrasonic destruction (Branson Sonifier 450, 3 KHz, 3 watts, 30 min) in a buffer of 8 M urea, 500 mM NaCl, 50 mM Tris-HCl pH 8.0. Metal affinity chromatography was performed by applying IDA Sepharose Fast Flow to a column prepared by binding nickel (Ni). The sample was loaded onto a column equilibrated with the same buffer containing the recombinant sucrase and then washed with the same buffer solution and then washed with the same buffer containing 50 mM imidazole to remove contaminating proteins. After that, elution was carried out with a buffer having an imidazole concentration as high as 500 mM, thereby selectively separating His-tagged sucrase. The purified sucrose through metal affinity chromatography underwent a refolding process to produce active sucrase.

Refolding ( refolding ) fair

In order to produce the target protein produced in an inactive form in an active form, a refolding process was carried out using a denatured sucrose purified by IMAC. The refolding process was performed at 4 ° C in a low-temperature room. The concentration of the 8 M urea was lowered to 1.6 M by 5-fold dilution using the refolding buffer solution of four conditions to induce primary refolding. Respectively. For the final antibody production, the active urease was ultrafiltrated to remove residual urea, and the buffer solution was exchanged with PBS (pH 7.4) and concentrated.

The composition of the buffer used for chromatography and refolding is shown in Table 3 below.

2. Experimental results

PCR To use as a model chain for Sucrase  synthesis

In this example, only 828 sucrose segments were expressed in Escherichia coli in the total sucrase-iso-maltase complex (Fig. 2). In addition, for stable expression in E. coli, the original DNA sequence was changed to the preferred codon of E. coli without changing the amino acid, and DNA synthesis was commissioned by Bioneer Co., Ltd., and the DNA was inserted into pGEM T vector. And used as a model chain for PCR (FIGS. 3 and 4).

Sucrase  Construction and expression confirmation of expression vector

PCR was performed using the synthesized sucrase gene as a model chain in order to remove 120 amino acids (360 bp) of N-terminal Sucracase and construct an expression vector into which a histidine purification tag was introduced. The primer sequences used in the PCR are as follows.

Primer 8: N-terminal

5 '- TGT ATG ATA CAT ATG CAC CAC CAC CAC CAC CAC TGG CAC ACG TGG GGA ATG TTC ACC CGG GAC

Primer 2: C-terminus

5 '- CAT CCA CGA AAC CGG ATC CTG ACT ACG AGT GAA ATT AAT TGT AGG GGA

Primer 3: N-terminal

5 '- ACT CGT AGT CAG GAT CCG GTT TCG TGG ATG AAA CTT TTG CTG CAG

Primer 4: C-terminus

5 '- TGT ATG ATA CTC GAG TTA TGA CCA GGT GAT TTG TAT TGG TTC ATC

Primer 8 is the restriction enzyme Nde I were designed to introduce a six-histidine tag for purification and cleavage site and sucrase azepin 121st amino acid is connected directly, the primer 7, sucrase azepin inside the BamH I cleavage site was introduced. Primer 3 is BamH < RTI ID = 0.0 > I restriction endonuclease cleavage site was introduced, and primer 4, which is a C-terminus, was introduced into Xho I cleavage site was introduced. The fragments obtained by PCR in the same manner were digested with restriction enzymes Nde I and BamH I, BamH I and Xho I, respectively, and then they were sequentially separated from the agarose gel and inserted into the pET22b (+) vector. The plasmid cloned as above is named pET22-6HrSucD120 and is shown in Fig. Expression vector pET22-6HrSucD120, in which the DNA sequence was correctly identified, was transformed into E. coli BL21 (DE3) and Rosetta-gami (DE3), respectively, and cultured and subjected to 10% electrophoresis (SDS-PAGE).

As a result, BL21 (DE3) / pET22-6HrSucD120 of Escherichia coli BL21 (DE3) and Rosetta-gami (DE3) transformants transformed with pET22-6HrSucD120 were found to express sucrase more than Rosetta-gami (DE3) / pET22-6HrSucD120 It is confirmed that it produces more efficiently. In addition, the production of sucrase was higher in the TB medium than in the LB medium. Most of the sucrose produced at 37 ° C after induction of IPTG was present in the non-insoluble fraction, and even if the temperature was lowered after induction, (Fig. 6 and Fig. 7). BL21 (DE3) / pET22-6HrSucD60 and BL21 (DE3) / pET22-6HrSucD120, which produce sucrase more efficiently than Rosetta-gami (DE3) transformants, have a high expression level, but both strains are ineffective In order to produce mold sucrase, active sucrase production was carried out through refolding process for antibody production. Since the molecular weight of sucrose produced by each transformant is large, IMAC Respectively.

IMAC Using Sucrase  refine

BL21 (DE3) / pET22-6HrSucD120 transformants were inoculated into 50 ml of LB liquid medium containing 50 / / ml of ampicillin for 14 hours in a shaking incubator at 37 캜 for purification of sucrose with 120 amino acids removed Growth strains were prepared. In the same manner, IPTG was added to 4 L of 1 L baffle flasks containing 250 ml of TB medium to a final concentration of 1 mM, followed by culturing to a maximum of 3 OD at 37 ° C. Protein was allowed to express. After the incubation, the culture was centrifuged at 5,000 rpm for 5 minutes to collect the cells. After the incubation, the cells were suspended in 100 ml of wash buffer I, ultrasonically disrupted, and only the insoluble fraction was recovered by centrifugation. In order to remove contaminating proteins from the insoluble fractions, they were sequentially suspended in a wash buffer II containing 2 M urea and a wash buffer III containing 4 M urea, sonicated and subjected to 10% electrophoresis (SDS-PAGE) 8 and 9).

As a result, 2 M urea edosaccharides were mostly present in the insoluble fraction, and in the presence of 4 M urea, sucrose was mostly present in the insoluble fraction, and most of the soluble fractions were present in the soluble fraction. Sucrose was finally suspended in 50 ml of a solubilization buffer containing 8 M urea and 0.5 M sodium chloride (NaCl), ultrasonically disrupted, and subjected to 10% electrophoresis (SDS-PAGE) (FIG. 10).

As a result, it was confirmed that sucrose dissolved mostly in soluble fraction, and filtration was performed to 0.22 ㎛ for purification. For the resin, 20 ml of IDA sepharose Fast Flow was used and 20 X 250 mm of Merck Co. was used. The column filled with resin was thoroughly washed with distilled water, and nickel having affinity for histidine was bound to the resin by using 200 ml of a nickel solution (NiSO ₄ ). Nickel ions not bound were removed with distilled water. Samples were injected into a column equilibrated with an equilibration buffer, and then sufficiently washed with a buffer. Sucrose was fractionally purified using an imidazole linear gradient of 50 mM to 500 mM using an elution buffer. Sucrose purified by IMAC was subjected to SDS-PAGE analysis, and gelation results confirmed a purification rate of 65% (FIG. 11).

Sucrase Refolding

Fig. 12 shows a schematic diagram of the sucrase refolding process.

As a result of the above-mentioned refolding process, it was confirmed visually that the formation of insoluble aggregates during the refolding process was significantly reduced in the case of sucrose in which 120 amino acids were removed, compared with the sucrose in which 60 amino acids were removed 13). SDS-PAGE analysis also confirmed that the amount of sucrase present in the total fraction and the amount of sucrase present in the soluble fraction were almost the same. In particular, it was confirmed that the refolding process was efficiently performed even when diluted with 50 mM Tris-HCl (pH 8.0) solution containing 0.15 M sodium chloride (NaCl) without addition of glycerol, arginine and cysteine (FIG.

For antibody production Sucrase  production

For the final production of sucukase for antibody production, BL21 (DE3) / pET22-6HrSucD120 transformants of sucrose in which 120 amino acids were removed were inoculated into 100 ml LB liquid medium containing 50 / / ml of ampicillin And cultured for 14 hours in a 37 ° C shaking incubator. The next day at 9 am, 5 L of each 1 L baffle flask containing 250 mL TB medium was inoculated with 5 mL of each, followed by culturing to 0.6 OD, adding IPTG at a concentration of 1 mM, and culturing to a maximum of 3 OD at 37 DEG C, Lt; / RTI > protein was allowed to express. After the incubation, the culture was centrifuged at 5,000 rpm for 5 minutes to collect the cells. After the incubation, the cells are immediately suspended in 400 ml of wash buffer II, ultrasonically disrupted, and centrifuged to remove the supernatant. The remaining pellet was resuspended in 200 ml of wash buffer III, ultrasonically disrupted, and centrifuged to remove the supernatant. The supernatant was finally suspended in 200 ml of the solubilization buffer, ultrasonically disrupted, and centrifuged to recover the supernatant. The sucrose dissolved in the soluble fraction was subjected to filter filtration at 0.22 mm for purification and IMAC was performed. 100 ml of purified sucrase in a metal affinity column was slowly dropped in a beaker using a pipette while stirring in a beaker containing 400 ml refolding solution (50 mM Tris-HCl, 0.15 M NaCl, pH 8.0) in a low temperature chamber 24 hour refolding reaction was induced. The sucrose that had been refolded was confirmed to be present in the soluble fraction by electrophoresis (SDS-PAGE). To prepare the final antibody, the buffer solution was replaced with PBS (pH 7.4) using ultrafiltration and the final concentration was adjusted to 1 Mg / ml to recover the final 40 ml, that is, 40 mg of active sucrase (Table 4 and Fig. 15).

II . Antibody production and validation

1. Enzyme-Linked Immunosorbent Assay ( ELISA )

The produced active sucrase was used as an immunogen to verify the production of the antibody. In order to test the antibody production against the antigen in mouse in vivo 7 days after first injection of sucrose and 4 days after second injection, blood was collected and serum was separated and assayed. The 96-well ELISA assay kit coated with the antigen at a concentration of 2 / / ml was prepared and each immunized mouse serum was diluted x5, x10, x50, x100 to verify antibody production.

16 is a graph showing the results of ELISA assays according to primary antigen immunity of sucrase. 17 is a graph showing the results of ELISA assays according to secondary antigen immunity of sucrase. FIG. 18 is a graph showing the results of comparing antibody production ability according to immunity frequency. FIG. As shown in FIG. 16 and FIG. 17, it was confirmed that the antibody was significantly generated in the mouse serum after the primary antigen injection and the secondary antigen injection as compared with the negative control (N.C).

FIG. 19 is a graph showing the number of anti-sccase monoclonal antibody clones, and FIG. 20 is a graph showing ELISA with dilution of 63 clones of the monoclonal antibody.

2. Western Blot (Western Blot)  Confirmation of expression used

Three antibodies of the present invention (SU63, SU27 and SU10) were diluted to 2000: 1. As a control, SI complex antibody from Santa Cruz Biotechnology was obtained and diluted to 2000: 1.

Samples were obtained from Sigma's rat intestinal acetone powder (protein concentration = 10 / / ml), and the results are shown in FIG.

Claims (10)

A method for producing an antibody against Sucrase-Isomaltase, which comprises using 120 saccharide-free sucrose as an immunogen.
The method according to claim 1,
A method for producing an antibody against sucrase-isomaltase, which comprises using sucrose having 120 amino acids at its N-terminal removed as an immunogen.
3. The method of claim 2,
A method for producing an antibody against sucrase-iso-maltase, which comprises the step of removing 120 amino acids at the N-terminus and preparing a sucrase expression vector into which a polyhistidine purification tag is introduced .
The method of claim 3,
And removing the 120 amino acids at the N-terminus and preparing a sucrase expression vector into which six histidine purification tags have been introduced.
The method according to claim 1,
Wherein the antibody is a monoclonal antibody. ≪ RTI ID = 0.0 > 11. < / RTI >
An antibody against sucrase-isomaltase produced according to the method of any one of claims 1 to 5.
A kit for diagnosing one or more of diabetes, obesity and digestive disorders comprising an antibody against sucrase-isomaltase according to claim 6.
A pharmaceutical composition for the treatment or prevention of one or more of diabetes, obesity and digestive disorders comprising an antibody against sucrase-isomaltase according to claim 6 as an active ingredient.
A recombinant expression vector comprising a sucrase sequence in which 120 amino acids are removed at the N-terminus and 6 histidine purification tags are introduced.
A transformant into which the recombinant expression vector of claim 9 is introduced.

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