CN117487019A

CN117487019A - Antibody of anti-human IgG protein and application thereof

Info

Publication number: CN117487019A
Application number: CN202311513135.3A
Authority: CN
Inventors: 虢雅洁; 杨正根; 张海珍; 庞志倡; 黄伟军; 陈校园
Original assignee: Guangzhou Kangsheng Biotechnology Co ltd
Current assignee: Guangzhou Kangsheng Biotechnology Co ltd
Priority date: 2023-11-14
Filing date: 2023-11-14
Publication date: 2024-02-02

Abstract

The invention discloses an antibody of an anti-human IgG protein and application thereof. The antibodies of some examples of the invention have high adsorption performance and good specificity to human IgG. The antibodies of some examples of the invention have better adsorption to human IgG than protein a. The antibody of some examples of the invention can be prepared into an IgG immunoadsorbent, well adsorb and remove excessive IgG, and provide a new direction for treating diseases caused by abnormal IgG.

Description

Antibody of anti-human IgG protein and application thereof

Technical Field

The invention belongs to the field of blood immunoadsorption, and in particular relates to an antibody for resisting human IgG protein and application thereof.

Background

Immunoglobulin (Ig) is produced by an organism after the organism is stimulated by an antigen (such as a pathogen), and the Immunoglobulin has the main function of reacting with the antigen to generate an antigen-antibody complex, thereby blocking the harm of the pathogen to the organism and causing the pathogen to lose the function of the pathogen. Immunoglobulins are classified into 5 classes including immunoglobulin G (IgG), immunoglobulin a (IgA), immunoglobulin M (IgM), immunoglobulin D (IgD), and immunoglobulin E (IgE). Wherein, igG is the most abundant in human serum, accounting for 75% of total immunoglobulin, is the most durable and important antibody in primary immune response, and plays an important role in antibacterial and antiviral processes. IgG abnormalities can lead to a variety of immune diseases, such as rheumatoid arthritis and systemic lupus erythematosus, which can be caused by elevated IgG. For pathogenesis of diseases, current treatment is mainly performed by immunotherapy with monoclonal antibodies, but the use of immunotherapy is limited by several factors, for example, repeated administration of high doses of biological drugs is required to achieve the effect of immunotherapy, and thus a series of autoimmune-mediated side effects (including immunogenicity, induction of anti-drug antibodies, serosis, etc.) may be induced.

IgG is divided into 4 subtypes, igG1, igG2, igG3 and IgG4, respectively, and is similar in overall structure, with Fc (Fragment crystallizable) constant regions exhibiting high sequence homology, consisting of a pair of heavy chain CH2 and CH3 constant domains, linked by a Hinge (Hinge) structure to two antigen-binding Fab (Fragment of antigen binding) variable regions, including VH and CH1 (heavy chain) and VL and ck/lambda (light chain) domains. The IgG4 subtypes differ greatly in the hinge and CH2 domains, respectively, mainly by the length of the hinge, i.e., the length of the IgG3 hinge is twice that of the Fc fragment, making the Fab fragment structurally distant from the Fc fragment, while the hinge length of IgG2/IgG4 is shorter, making the Fab fragment structurally close to the Fc fragment. Currently marketed monoclonal antibodies are mostly domain proteins, subtypes comprise IgG1, igG2 and IgG4, and have different mechanisms for treating diseases, and Fc fragments of the monoclonal antibodies can be combined with protein A, but the proteins are easy to degrade in the storage and use processes, so that the problems of large medicine batch difference, immunogenicity and the like are caused.

Unlike conventional antibodies, nanobodies are single domain antibodies that have only heavy chains and no light chains, have only one variable domain and antigen binding, and are about 12-17 kD in size, which is only one tenth of conventional antibodies (150 kD). Furthermore, single domain antibodies have only one domain with disulfide bonds, which fold into a relatively stable structure, and studies have shown that single domain antibodies retain antigen binding capacity after one week of incubation at 37 ℃ allowing more stringent chemical and physical conditions to be used during treatment or modification. In addition, single domain antibodies are small in size, which is beneficial for reducing the number of potentially immunogenic epitopes, while having rapid blood clearance and resistance to aggregate formation, resulting in lower immunogenicity. Single domain antibodies have shown great potential as tools in different biotechnology fields, such as diagnosis and therapy.

The development of an antibody capable of specifically adsorbing IgG, which can maintain high enough antigen specificity and affinity and high yield expression, has very practical significance for developing corresponding immunotherapeutic preparations.

Disclosure of Invention

The invention aims to overcome at least one defect of the prior art and provides an anti-human IgG protein antibody and application thereof.

The technical scheme adopted by the invention is as follows:

in a first aspect of the invention, there is provided:

an antibody of anti-human IgG protein is composed of framework regions FR 1-FR 4 and antigen binding regions CDR 1-CDR 3, wherein the amino acid sequences of the CDR 1-CDR 3 are respectively as follows: CDR1: QYAMG, CDR2: AIRRSGGSTYYADSVEG, CDR3: GGRDTYGYKLPTTRVDY.

In some examples of antibodies, the amino acid sequences of FR 1-FR 4 are respectively: FR1: QVQLQESGGGLVQAGGSLRLSCAVSGNTLS, FR2: WFRQAPGNEREFVA, FR3: RFTISRDSAKNTVYLQMNSLQPEDTAVYYCAA, FR4: WGQGTQVTVSS.

In some examples of antibodies, they are single domain antibodies.

In some examples of antibodies, the method of making comprises:

s1) connecting a nucleotide sequence corresponding to the antibody with a pET-28a vector, wherein the enzyme cutting sites are NdeI and XhoI;

s2) transferring the connection product of the S1) into BL21 (DE 3) competent bacteria for transformation;

s3) expression of recombinant protein: monoclonal colony with correct sequence of PCR and sequencing identification strip is inoculated in LB liquid culture medium containing kanamycin and cultured until OD ₆₀₀ =0.6 to 0.8, and after centrifugation to collect the cells, crushing at low temperature and centrifugation to collect the protein supernatant;

s4) purification of recombinant protein: purifying the protein supernatant by an affinity chromatography column, and collecting elution peaks to obtain the antibody protein.

In a second aspect of the invention, there is provided:

an immunoadsorbent comprising a solid support, wherein the surface of the solid support is coupled with an antibody according to the first aspect of the invention.

In some examples of immunoadsorbers, the solid support is selected from at least one of agarose, chitosan, sephadex, resin, and cellulose microspheres.

In a third aspect of the invention, there is provided:

the use of an antibody according to the first aspect of the invention in the preparation of an IgG immunoadsorbent.

In some examples of application, the IgG is selected from at least one of the IgG1, igG2, igG3, and IgG4 subtypes.

In some examples of applications, the IgG immunoadsorbers are blood IgG immunoadsorbers.

In a fourth aspect of the invention, there is provided:

the application of the antibody in the first aspect of the invention in preparing medicines for treating and/or preventing diseases caused by IgG abnormality.

In some examples of use, the disease caused by IgG abnormalities is an autoimmune-related disease.

In examples of some applications, autoimmune-related diseases include, but are not limited to, rheumatoid arthritis, systemic lupus erythematosus, and multiple myeloma of the IgG type, among others.

In a fifth aspect of the invention, there is provided:

the use of an antibody according to the first aspect of the invention in the preparation of an immunoglobulin IgG purification agent.

The beneficial effects of the invention are as follows:

the antibodies of some examples of the invention have high adsorption performance and good specificity to human IgG.

The antibodies of some examples of the invention have better adsorption to human IgG than protein a.

The antibody of some examples of the invention can be prepared into an IgG immunoadsorbent, well adsorb and remove excessive IgG, and provide a new direction for treating diseases caused by abnormal IgG.

Drawings

Fig. 1 is SEQ ID No.:1 to different IgG subtypes.

Fig. 2 is SEQ ID No.:2 to different IgG subtypes.

Fig. 3 is SEQ ID No.:3 to different IgG subtypes.

Fig. 4 is SEQ ID No.:4 to different IgG subtypes.

Fig. 5 is SEQ ID No.:5 to bind to different IgG subtypes.

FIG. 6 shows the results of binding activity of different single domain antibodies to protein A on IgG.

Detailed Description

In some examples of antibodies, they are single domain antibodies. The peptide chain of the single-domain antibody is shorter, the preparation is easy, and the stability is good.

Antibodies can be prepared by conventional methods, and in some examples, the preparation method comprises:

s3) expression of recombinant protein: monoclonal colony with correct sequence of PCR and sequencing identification strip is inoculated in LB liquid culture medium containing kanamycin and cultured until OD ₆₀₀ =0.6 to 0.8, and after the cells are collected by centrifugation using IPTG inductionCrushing at low temperature and centrifugally collecting protein supernatant;

The preparation method

In order to more clearly demonstrate the technical scheme, objects and advantages of the present invention, the present invention is described in further detail below with reference to specific embodiments.

Example 1: establishment of phage antibody library of alpaca combined with human immunoglobulin G (IgG)

Referring to CN114316051a, a alpaca phage antibody library was established, briefly as follows:

s1) immunizing alpaca with human IgG mixed by equal proportion of 4 subtype proteins (Abcam) of IgG, and collecting peripheral blood mononuclear cell PBMC;

s2) extracting RNA from the PBMC and reversely transcribing the RNA into cDNA;

s3) after PCR amplification of the target sequence, the target sequence is connected to a phagemid vector pHIAT-1 through HindIII and NotI cleavage sites, and then transformed into escherichia coli TG1 to form an original phage library;

s4) adding the helper phage M13K07 to the TG1 strain growing to the logarithmic phase, culturing overnight, and centrifugally collecting the supernatant;

s5) precipitation of phagemid with PEG, followed by re-suspension of phage with PBS and filter sterilization with 0.45 μm filter to obtain phage VHH antibody library with a library capacity of 4.6X10 ¹³ 。

Example 2: phage library screening

(1) Round 1 screening of phage antibodies

S1) titer of 1.2X10 as determined by helper phage M13K07 ¹⁰ pfu/mL, TG1 was infected with helper phage M13K 07;

s2) coating human IgG on an ELISA plate, 0.5 mug/hole, overnight at 4 ℃, and washing the plate for 3 times;

s3) preparing 5% skimmed milk powder (sealing liquid) by using PBST, sealing, incubating for 2h at 37 ℃ at 200 mu L/hole, and washing the plate for 3 times;

s4) adding 100 mu L of phage library solution into each hole, incubating for 2h at 37 ℃, and washing the plate for 3 times;

s5) adding 100 mu L of Glycine-HCl buffer solution into each hole, gently shaking at room temperature for 10min, then sucking out eluent and rapidly adding 80 mu L of 1M Tris-HCl buffer solution; taking out 10 μl for determining titer, adding the rest liquid into TG1 bacterial liquid grown to logarithmic phase of 5 mL, standing at 37deg.C for 30 min;

s6) adding 2 XYT culture medium to 10 mL of total volume, and culturing at 37 ℃ and 220 rpm for 30 min-1 h;

s7) ampicillin (Amp) was added to a final concentration of 100. Mu.g/mL, and the bacterial suspension was incubated at 37℃and 250 rpm to OD ₆₀₀ =0.4-0.6；

S8) adding helper phage M13KO7 into the bacterial liquid, standing at 37 ℃ for 30 min, and culturing at 37 ℃ for 45 min-1 h at 250 rpm;

s9) centrifugation at 5000 rpm at 4℃for 20 min, discarding the supernatant, and resuspending the cells with an equal volume of 2 XYT-Amp-kana (kanamycin) medium (containing 100. Mu.g/mL Amp, 30. Mu.g/mL kana), at 30℃and 220 rpm;

s10) centrifuging at 8000rpm for 20 min at 4 ℃, taking the supernatant, adding 1/5 volume of 20% PEG/NaCl solution, fully and uniformly mixing, and standing on ice or at 4 ℃ for 1-2 h;

s11) centrifugation at 8000rpm at 4℃for 30 min, discarding the supernatant, re-suspending the pellet with 1 mL sterile PBS, and then centrifugation at 8000rpm at 4℃for 10min, wherein the pellet is phage antibody pellet.

(2) Round 2 screening of phage antibodies

S1) coating human IgG on an ELISA plate, 1 mug/hole, overnight at 4 ℃, and washing the plate for 6 times;

s2) sealing by using sealing liquid, incubating for 2h at 37 ℃ and washing the plate for 6 times, wherein 200 mu L/hole is formed;

s3) adding 100 mu L of phage library solution for 1 st round screening into each hole, incubating for 2h at 37 ℃ and washing the plate for 6 times;

the rest of the procedure is the same as the first round of screening.

(3) Round 3 screening of polyclonal phage antibodies

Coating human IgG on an ELISA plate, coating the ELISA plate with 0.1 mu g/hole, standing overnight at 4 ℃, and washing the ELISA plate for 3 times; sealing by using sealing liquid, incubating for 2h at 37 ℃ at 200 mu L/hole, and washing the plate for 3 times; 100 mu L of phage library solution after 2 nd round screening is added into each hole, incubated for 2h at 37 ℃ and washed for 10 times; the rest of the procedure was the same as round 1 screening.

(4) Monoclonal phage detection

S1) infecting TG1 with phage after 3 rd round screening, diluting and coating on a flat plate for culture, and then picking 96 monoclonal antibodies;

s2) ELISA detection is carried out by taking the original library as a negative control, and OD is selected ₄₅₀ The value is 2.1 times greater than that of the original library, and the primary positive clone is sequenced;

s3) according to the sequencing result, removing the repeated sequence, and screening 5 sequences with better IgG adsorption effect as alternative sequences, wherein the amino acid sequences of the 5 sequences are respectively shown as SEQ ID NO. 1-SEQ ID NO. 5.

Structural function analysis is carried out on 5 single-chain antibodies obtained by screening, and the result is as follows:

SEQ ID NO.：1：

MQVQLQESGGGLVQPGGSLRLSCVPSGRTFSTYAMAWHRQAPGKQRELVASITSDGSTNYADSVKARFTISRDNAKNTVYLQMNSLKPEDTAVYYCAGRFLGYASSNAYHEALYNYDYWGQGTQVTVSS

wherein CDR1: TYAMA (SEQ ID NO.: 6), CDR2: SITSDGSTNYADSVKA (SEQ ID NO.: 7), CDR3: RFLGYASSNAYHEALYNYDY (SEQ ID NO.: 8); FR1: QVQLQESGGGLVQPGGSLRLSCVPSGRTFS (SEQ ID NO.: 9), FR2: WHRQAPGKQRELVA (SEQ ID NO.: 10), FR3: RFTISRDNAKNTVYLQMNSLKPEDTAVYYCAG (SEQ ID NO.: 11), FR4: WGQGTQVTVSS (SEQ ID NO.: 12).

SEQ ID NO.：2：

MQVQLQESGGGLVQAGGSLRLSCAVSGNTLSRYAMGWFRQAPGKEREFVGSIRWNNGNTYLVDSVKGRFTISGDNAHDTVHLQMTSLKPEDTGVYFCVaRSFGTGQWDYWGQGTQVTVSS

Wherein CDR1: RYAMG (SEQ ID NO.: 13), CDR2: SIRWNNGNTYLVDSVKG (SEQ ID NO.: 14), CDR3: RSFGTGQWDY (SEQ ID NO.: 15); FR1: QVQLQESGGGLVQAGGSLRLSCAVSGNTLS (SEQ ID NO.: 16), FR2: WFRQAPGKEREFVG (SEQ ID NO.: 17), FR3: RFTISGDNAHDTVHLQMTSLKPEDTGVYFCVA (SEQ ID NO.: 18), FR4: WGQGTQVTVSS (SEQ ID NO.: 12).

SEQ ID NO.：3：

MQVQLQESGGGLVQPGESLRLSCAASPRTFSVYAMGWYRQAPGKQRELVaTIRWNNAATNYADSVKGRFTISRDNAKDTLYLQMNSLKPEDTAVYYCNAQNSWRNIWGQGTQVTVSS

Wherein CDR1: VYAMG (SEQ ID No.: 19), CDR2: TIRWNNAATNYADSVKG (SEQ ID NO.: 20), CDR3: QNSWRNI (SEQ ID No.: 21); FR1: QVQLQESGGGLVQPGESLRLSCAASPRTFS (SEQ ID NO.: 22), FR2: WYRQAPGKQRELVA (SEQ ID NO.: 23), FR3: RFTISRDNAKDTLYLQMNSLKPEDTAVYYCNA (SEQ ID NO.: 24), FR4: WGQGTQVTVSS (SEQ ID NO.: 12).

SEQ ID NO.：4：

MQVQLQESGGGLVQAGGSLRLSCAVSGIAFEVFNMGWFRQAPGNEREFVaAANWKSGSTYYADSVKGRFTISRDSAKNTVYLQMNSLQPEDTAVYYCASRFLPYASSNAYHEALYNYDYWGQGTQVTVSS

Wherein CDR1: VFNMG (SEQ ID No.: 25), CDR2: AANWKSGSTYYADSVKG (SEQ ID NO.: 26), CDR3: RFLPYASSNAYHEALYNYDY (SEQ ID NO.: 27); FR1: QVQLQESGGGLVQAGGSLRLSCAVSGIAFE (SEQ ID NO.: 28), FR2: WFRQAPGNEREFVA (SEQ ID NO.: 29), FR3: RFTISRDSAKNTVYLQMNSLQPEDTAVYYCAS (SEQ ID NO.: 30), FR4: WGQGTQVTVSS (SEQ ID NO.: 12).

SEQ ID NO.：5：

MQVQLQESGGGLVQAGGSLRLSCAVSGNTLSQYAMGWFRQAPGNEREFVaAIRRSGGSTYYADSVEGRFTISRDSAKNTVYLQMNSLQPEDTAVYYCAAGGRDTYGYKLPTTRVDYWGQGTQVTVSS

Wherein CDR1: QYAMG (SEQ ID No.: 31), CDR2: AIRRSGGSTYYADSVEG (SEQ ID NO.: 32), CDR3: GGRDTYGYKLPTTRVDY (SEQ ID NO.: 33); FR1: QVQLQESGGGLVQAGGSLRLSCAVSGNTLS (SEQ ID NO.: 16), FR2: WFRQAPGNEREFVA (SEQ ID NO.: 29), FR3: RFTISRDSAKNTVYLQMNSLQPEDTAVYYCAA (SEQ ID NO.: 34), FR4: WGQGTQVTVSS (SEQ ID NO.: 12).

Example 3: antibody in vitro recombinant expression and purification

S1) connecting a pET-28a vector with the pET-28a vector through NdeI and XhoI enzyme cutting sites after double enzyme cutting treatment of NdeI and XhoI, wherein the nucleotide sequences corresponding to the amino acid sequences shown in SEQ ID NO. 1-5 are respectively connected with the pET-28a vector through NdeI and XhoI enzyme cutting sites;

s2) transferring the connection product into BL21 (DE 3) competent bacteria for transformation;

s3) selecting a monoclonal colony, carrying out PCR and sequencing to identify that the band sequence is correct, and then carrying out recombinant protein expression:

s4) carrying out plate streaking on bacterial liquid, picking a monoclonal colony, inoculating the monoclonal colony into LB liquid medium containing kanamycin for culture, and then carrying out 1:100 proportion expansion culture to OD ₆₀₀ =0.6-0.8, adding IPTG with a final concentration of 1 mM, inducing for 6h, centrifuging to collect thalli, crushing at low temperature, and centrifuging to collect protein supernatant;

s5) purifying recombinant protein: filtering the supernatant protein after crushing and centrifugation through a 0.45 mu m filter membrane, and purifying by an affinity chromatography column (nickel ion chelating filler with His tag); balancing the chromatographic column by using 20 mM Tris-HCL buffer solution, slowly adding the protein into the chromatographic column, respectively using 10 mM imidazole buffer solution and 40 mM imidazole buffer solution for washing, using 250 mM imidazole buffer solution for eluting recombinant protein, and collecting elution peaks to obtain the alpaca single domain antibody protein.

The purity of the target protein can be identified by 15% SDS-PAGE gel running analysis of the elution peak.

Example 4: detection of binding Activity of Single-Domain antibodies on human IgG

S1) respectively adding coating liquid (respectively containing mixed liquid of IgG1, igG2, igG3, igG4 and 4 subtype of IgG in equal proportion) into ELISA plates (96-well plates), diluting the concentration to be 1ug/mL, and incubating for 2 hours at 37 ℃ in each well;

s2) removing the coating liquid, adding a blocking liquid (5% BSA), 200 mu L of each well, and washing the plate for 5 times at 4 ℃ overnight; adding the single-domain antibody into the holes coated with the 5 coating liquids after gradient dilution, and adding the protein A into the holes coated with the IgG4 subtype equal proportion mixed liquid after gradient dilution, wherein the gradient dilution concentration is respectively 15.625, 31.25, 62.5, 125, 250, 500 and 1000pg/mL, and the concentration is 100 mu L of each hole, and the plate is incubated for 2 hours at room temperature and washed for 5 times; adding anti-His and HRP labeled antibodies (antibody dilution ratio is 1:5000) respectively, incubating for 1h at room temperature in 100 mu L of each well, and washing the plate for 5 times;

s3) respectively adding the two-component TMB color development liquid, wherein each hole is 100 mu L, and developing at room temperature in a dark place for 5-10min; the ELISA plate with good color development was removed, and 100. Mu.L of 1M H was added to each plate ₂ SO ₄ Stop solution, 100. Mu.L per well, absorbance at a wavelength of 450nm was measured by an enzyme-labeled instrument.

The results are shown in FIGS. 1-6. The results indicate that all 5 single domain antibodies can bind to the 4 subtypes of human IgG, with increasing concentration the binding activity also increasing progressively, with binding activity to IgG1 and IgG4 subtypes being highest; in addition, the binding activity of the single domain antibodies numbered SEQ ID NO.1, SEQ ID NO.3, SEQ ID NO.4 and SEQ ID NO.5 to IgG is higher than that of protein A, and the binding activity of protein A to IgG is basically equivalent to that of SEQ ID NO. 2.

Example 5: synthesis of immunoadsorbers

S1) 10 mL activated reaction solution (sodium borohydride: 0.02 g, naOH:0.24 g) and 10 mL BDGE, activating at 37 ℃ and 120 rpm for 2.5-h, then cleaning to pH 5.0-7.0, and vacuum drying;

s2) to the filler drained in step S1) 10 mL coupling buffer (ammonium sulfate: 3.96 g; naOH:0.27 g) and 10 mL, coupling reaction is carried out at 37 ℃ and 120 rpm for about 8 h, and then the alpaca single domain antibody solution is washed for more than 10 times and pumped out;

s3) adding 20 mL of 1M ethanolamine solution into the filler pumped in the step S2), carrying out end-capping reaction at 37 ℃ and 120 rpm for overnight, then washing for more than 10 times, pumping, and adding 20% ethanol for storage for later use.

Example 6: detection of adsorption performance of immunoadsorbent on human IgG

Referring to the method described in example 5 of CN111057153a, the adsorption performance of human IgG was detected by a static adsorption method, and the procedure was briefly as follows:

s1) preparing an immunoadsorbent according to the method, adding 10 mL human blood plasma into the 1 mL immunoadsorbent, placing the mixture in a shaking table, and slowly shaking the mixture at room temperature to obtain 1 h;

s2) after the reaction is finished, adding the reaction solution into a disposable affinity chromatography column, washing with about 100 mL balance liquid (PBS), eluting with 40 mL eluent (citric acid 2.1 g/L and NaC 1.0 g/L), collecting an eluting peak, detecting the value of OD280 by ultraviolet, and detecting the adsorption performance (mg/mL) = [ (OD 280/1.38) ×40]/1;

s3) detecting the content of immunoglobulin IgA and IgM in the blood plasma by using a biochemical analyzer, and determining the nonspecific adsorption amount.

The results are shown in Table 1.

TABLE 1 detection of adsorption Performance of immunoadsorbent to each immunoglobulin

As can be seen from Table 1, the immunoadsorbent formed by coupling 5 single domain antibodies with the solid phase carrier has high adsorption performance on human IgG, wherein the protein number SEQ ID NO.1 has the highest adsorption performance, the overall difference is not very large, and the 5 immunoadsorbents have low nonspecific adsorption on IgA and IgM and good specificity.

The above description of the present invention is further illustrated in detail and should not be taken as limiting the practice of the present invention. It is within the scope of the present invention for those skilled in the art to make simple deductions or substitutions without departing from the concept of the present invention.

Claims

1. An antibody against human IgG protein, consisting of framework regions FR1 to FR4 and antigen binding regions CDR1 to CDR3, characterized in that the amino acid sequences of CDR1 to CDR3 are respectively: CDR1: QYAMG, CDR2: AIRRSGGSTYYADSVEG, CDR3: GGRDTYGYKLPTTRVDY.

2. The antibody of claim 1, wherein the amino acid sequences of FR1 to FR4 are respectively: FR1: QVQLQESGGGLVQAGGSLRLSCAVSGNTLS, FR2: WFRQAPGNEREFVA, FR3: RFTISRDSAKNTVYLQMNSLQPEDTAVYYCAA, FR4: WGQGTQVTVSS.

3. The antibody according to claim 1 or 2, characterized in that it is prepared by a process comprising:

4. An immunoadsorber comprising a solid support coupled to a surface of the solid support with the antibody of any of claims 1 to 3.

5. The immunoadsorber of claim 4 wherein the solid support is selected from at least one of agarose, chitosan, sephadex, resin and cellulose microspheres.

6. Use of an antibody according to any one of claims 1 to 3 for the preparation of an IgG immunoadsorbent.

7. Use of an antibody according to any one of claims 1 to 3 for the preparation of a medicament for the treatment and/or prophylaxis of a disease caused by IgG abnormalities.

8. The use according to claim 6, wherein the disease caused by IgG abnormalities is an autoimmune-related disease.

9. Use of an antibody according to any one of claims 1 to 3 for the preparation of an immunoglobulin IgG purification agent.

10. The use according to claim 6, 7 or 9, wherein the IgG is selected from at least one of the IgG1, igG2, igG3 and IgG4 subtypes.