161 results about "Protein A" patented technology

The invention belongs to the technical field of biological detection, and discloses a kit and a method for quantitatively detecting residual quantity of host cell protein of pichia pastoris in order to solve the problems of limit of quantitation and low detection sensitivity of an existing detection method. According to the present invention, the empty plasmid without the recombinant human serum albumin gene is introduced into the pichia pastoris, and purification is performed by combining the Protein A chromatographic column and the host cell protein coupling affinity column, such that the prepared polyclonal antibody can be effectively used for the quantitative detection of the residual amount of the pichia pastoris host cell protein in the biological product; the kit formed by the polyclonal antibody has good accuracy and repeatability on the quantitative detection of the host cell protein residues in the pichia pastoris source biological products, the quantification limit is 0.2 ng / mL, and the kit provided by the invention can meet the quantitative detection of the host cell protein residues in all the pichia pastoris source biological products.

The invention provides a synthesis method of adsorption resin for removing immune globulin, and relates to a high polymer material synthesis technology, polyethylene glycol (PEG) or sulfobetaine (SBMA) is grafted through RAFT polymerization, the thickness of a grafting layer is 50-150nm, the nonspecific adsorption capacity of albumin is less than 5ng / cm < 2 >, photosensitive groups (such as phenyl azide) and ultraviolet light (254nm) are introduced to trigger crosslinking, and the coating shedding rate is less than 0.5% / time. According to the present invention, the cyclic stability is improved by 2 times, the Protein A directional capture antibody is grafted on the surface of the acrylic resin grafted with the polyethylene glycol or sulfobetaine, the IgG adsorption capacity achieves 150 mg / g, the specificity is more than 95%, the polyethylene glycol (PEG) is grafted on the surface of the magnetic particle by using ATRP / RAFT controllable polymerization, the organic solvent use amount is reduced by more than 80%, and the product adsorption capacity achieves 150 mg / g.

The invention discloses a preparation method of a monomeric protein and hydrophobic transmembrane protein complex, which comprises the following steps: 1) preparing a protein A containing the monomeric protein, the C end of the monomeric protein in the protein A having a connection sequence for connecting with the hydrophobic transmembrane protein; the connecting sequence comprises at least two amino acids; preparing a protein B containing a hydrophobic transmembrane protein monomer; and 2) connecting the protein A with the protein B, and polymerizing the hydrophobic transmembrane protein monomers in the plurality of protein B to form the hydrophobic transmembrane protein, thereby obtaining the monomeric protein and hydrophobic transmembrane protein complex.

A pharmaceutical composition for enhancing radiation therapy, containing a fusion protein dimer is disclosed. The fusion protein dimer includes an IL-2 protein and a CD80 protein. A method of radiation therapy for cancer, using the composition is also disclosed. The composition for enhancing radiation therapy may increase the effect of radiation therapy in cancer treatment.

Provided herein are methods for purifying polypeptides (e.g., antibodies) comprising an Fc region by Protein A chromatography; methods for using wash solutions comprising benzoate and / or benzyl alcohol during Protein A chromatography; and methods for conditioning the harvest using sodium benzoate prior to Protein A chromatography. [Selected Figure] Figure 1

The invention provides a method for detecting an anti-C1 esterase inhibitor neutralizing antibody in a biological sample, and the method mainly utilizes the characteristic that protein A resin is combined with an Fc segment of the antibody to capture the antibody (containing the anti-C1 esterase inhibitor neutralizing antibody), so that the C1 esterase inhibitor and complement component 1s (C1s) in the biological sample after thermal inactivation are removed; furthermore, an antibody (containing a neutralizing antibody) or an anti-C1 esterase inhibitor compound on the protein A resin is subjected to acid dissociation through an acidolysis solution, so that not only can the anti-C1 esterase inhibitor neutralizing antibody existing in a free form in a biological sample be detected, but also the anti-C1 esterase inhibitor neutralizing antibody existing in a combined form in the biological sample can be detected.

To provide a glycan preparation method for preparing labeled glycans quickly from glycoproteins.SOLUTION: A glycan preparation method comprises: a releasing step in which a glycosidase is allowed to act on a glycoprotein immobilized on a solid phase in a container to obtain a released product containing glycans; and a labeling step in which a labeling reagent is added to the released product in the container to obtain a labeled product containing labeled glycans, wherein the glycoprotein is an antibody, the solid phase has on its surface a ligand selected from the group consisting of protein A, protein G, protein L, protein H, protein D, and protein Arp, and the labeling reagent comprises a reducer, a solution and at least one selected from the group consisting of 8-aminopyrene-1,3,6-trisulfonic acid, a sodium salt thereof, and 9-aminopyrene-1,4,6-trisulfonic acid.SELECTED DRAWING: None

Disclosed herein are improved methods for quantifying monoclonal antibody (mAb) titer using Protein A affinity High-Performance Liquid Chromatography (HPLC). The methods address inaccuracies caused by mAb adsorption to sample vial surfaces by incorporating a surfactant into the mobile phase used for sample dilution. This approach enhances the accuracy, linearity, and robustness of the titer assay, making it suitable for process control and quality assessment in biopharmaceutical development and manufacturing. The methods can be applied as a platform approach for various mAb products.

A new technique for improving the secretion production of a heterologous protein by a coryneform bacterium is developed, and thus a method for the secretion production of a heterologous protein is provided. A coryneform bacterium having a secretion production ability of a heterologous protein and modified to maintain a phoS gene having a specific mutation is cultured to produce a heterologous protein by secretion.

The present application provides an isolated antigen-binding protein, comprising: a first antigen-binding domain and a second antigen-binding domain, wherein the first antigen-binding domain specifically binds to TNF-like protein A (TL1A), and the first antigen binding domain and the second antigen binding domain are different.

This invention generally relates to methods for enriching antibodies of interest. Specifically, this invention relates to enriching therapeutic antibodies from upstream cell culture processes using protein A chromatography in the form of a centrifugal column for product quality property profiling analysis.

The present disclosure provides a nanobody platform having a high affinity purification on protein A, wherein the nanobodies may incorporate diverse bioactive peptides, lipid or glycoside in its CDR1 and / or CDR3 regions. The present disclosure also provides a peptide-modified nanobody comprising non-toxic bioactive peptides and that exhibit potent anti-tumor activity. Moreover, the peptide-modified nanobody is able to be combined with other technologies, such as but not limited to bispecific antibodies and antibody-drug conjugates. Further, the present disclosure also provides production processes of the nanobodies and their use as a treatment and diagnostic agents.

The present disclosure relates to a method for improving the quality of glycosylated antibody drug conjugates (DAR distribution, stability, etc.) using activated carbon. Specifically, the present disclosure employs hydrophobic interaction chromatography (HIC) column, protein A chromatography, activated carbon stirring, and buffer exchange, alone or in series, to remove free glycosyltransferases. As a result, the purity of the glycosylated antibody drug conjugates is improved, and the degradation of the antibody drug conjugates is prevented. Ultimately, the drug substance (DS) of OBI-902 (anti-TROP2 antibody drug conjugate) and OBI-904 (anti-Nectin-4 antibody drug conjugate) is further determined.

The invention discloses an efficient purification process of a bispecific antibody and a special chromatography system thereof. The efficient purification process of the bispecific antibody comprises the following steps: pretreatment: performing 0.22 mu m microfiltration on a cell culture supernatant to remove cell debris, and performing deep filtration to reduce turbidity to be less than or equal to 1NTU so as to reduce subsequent chromatography medium pollution; carrying out improved Protein A affinity chromatography, namely carrying out affinity chromatography by adopting an agarose medium modified by a recombinant Protein A ligand, taking 20mM Tris-HCl as a loading buffer solution, and taking the pH value of the loading buffer solution as 7.4, taking 100mM citric acid as an elution buffer solution, and taking the pH value of the elution buffer solution as 3.2-3.5; performing mixed mode chromatography: adopting a composite mode medium containing a benzamidine functional group, taking 50mM sodium phosphate as a buffer solution, adjusting the pH value to 6.0-6.5, adjusting the NaCl concentration to 0.1-0.3 M, and specifically removing a double-antibody polymer and a mismatched isomer by utilizing a hydrophobic effect and an ion exchange synergistic effect; and performing nanoscale filtration and terminal treatment: removing viruses by adopting a virus filtration membrane with the aperture of 30nm, and performing 0.22 mu m sterile filtration to obtain a final product. According to the process, the purification efficiency, the yield and the product purity are remarkably improved, and the process is suitable for efficient purification of the bispecific antibody.

A dispersion solution contains a complex of cerium oxide nanoparticle with protein in which a hydrodynamic diameter and zeta potential of the protein are maintained. The dispersion solution is produced by mixing a solution containing the protein with a solution containing a cerium (III) ion or with a cerium (III) salt followed by adding an oxidizing agent thereto.

The invention relates to application of IGFBP7 in clinical diagnosis of colorectal cancer and application of IGFBP7 as a drug target. The research shows that the expression quantity of IGFBP7 secreted by tumor endothelial cells is continuously reduced in the colorectal tumor formation process related to inflammation. Functional analysis proves that the endothelial-derived IGFBP7 is secreted into a tumor microenvironment and plays a role in resisting angiogenesis. In addition, the CRC cells can actively ingest the vesicles containing the IGFBP7. The IGFBP7 reduces the activity of a TGF-beta1 signal channel by inhibiting the expression of EGR1, thereby inhibiting the proliferation and migration of tumor cells. What is worthy of attention is that VAPA (Vesicle-associated Membrane Protein Associated Protein A) is identified to be a key factor for mediating IGFBP7 vesicles to be transferred to lysosome, and VAPA promotes the degradation of IGFBP7, so that the cancer suppression function of the IGFBP7 is weakened. The endothelial cell-derived IGFBP7 inhibits the progress of CRC (cyclic redundancy check) through an EGR1 / TGF-beta 1 pathway, and VAPA-mediated lysosome degradation limits the cancer inhibition effect of the endothelial cell-derived IGFBP7. The discovery emphasizes that the endothelial cell-derived IGFBP7 is a promising therapeutic target in the field of colorectal cancer.

The invention discloses a bispecific antibody coupling drug targeting CD24 and HER2 and a preparation method and application thereof.The bispecific antibody coupling drug comprises an anti-CD24 heavy chain, an anti-CD24 light chain, an anti-HER2 heavy chain, an anti-HER2 light chain, a tetrapeptide linker and a topoisomerase I inhibitor exatan derivative, the DAR value of the bispecific antibody coupling drug is 9.25, and the anti-CD24 heavy chain, the anti-HER2 light chain, the tetrapeptide linker and the topoisomerase I inhibitor exatan derivative are different. The compound has strong cytotoxicity and internalization ability on breast cancer cells, not only can specifically target tumor tissues, but also can release drugs to kill target cells and adjacent tumor cells, and can significantly inhibit growth of breast cancer tumors. An antibody part DACH023 in the bispecific antibody coupling medicine is the same as a traditional IgG molecule, a traditional monoclonal antibody structure is reserved to the maximum extent, due to the existence of an Fc fragment, a common Protein A column affinity chromatography method can be adopted for purification, and large-scale production and purification are facilitated.

A local-global template search method of multi-domain protein, first, input the three-dimensional structure of each single domain of the multi-domain protein to be assembled, set the number R of templates to be screened in local evaluation; then, score the alignment of each template in the multi-domain protein structure library with each two consecutive domains, respectively calculate the local score of each two consecutive domains from N terminal to C terminal and from C terminal to N terminal, select the template with the highest local score as the optimal local template; then, again for each template in the multi-domain protein structure library, perform local evaluation by structure alignment of each domain and template through TM-align, and calculate the score of the template according to the local score of each single domain, select the top R templates with high score for global evaluation; in global evaluation, the alignment of different domains is not allowed to overlap, select the template with the highest global score as the optimal global template; finally, output the optimal local template and the final full-length template. The application improves the search precision of the template.

In certain embodiments, the present invention provides novel antibody purification methods and systems using a potentially simple and cost-efficient means. In some embodiments, customized Z-33 derived from Staphylococcus aureus Protein A is used to construct immuno-amphiphile molecules which can assemble into immunofibers in aqueous solution with bioactive epitopes on the surface and have IgG binding ability.

This invention relates to a high-titer prealbumin antibody purification method and its application, belonging to the field of biotechnology. The method utilizes Protein A affinity chromatography to capture total IgG from antiserum, followed by purification using an affinity chromatography column prepared by targeted conjugation of a specific sequence peptide. The antibody purified by this method achieves a titer of 1:256,000 in ELISA detection, with a half-maximal effective concentration (EC50). 50 The antibody concentration was 3.2 ng / mL, exhibiting extremely high affinity and reactivity. When used in a double-antibody sandwich chemiluminescent immunoassay, it achieved a detection limit of 0.08 µg / mL, a wide dynamic range (0.08–400 µg / mL), and a titer retention rate as high as 88% after accelerated storage at 37°C for 14 days, demonstrating significantly better stability than antibodies prepared by traditional methods. This invention provides a highly active and stable core antibody raw material for the preparation of high-performance immunodiagnostic reagents.

To provide a new composition for suppressing the accumulation of glycated proteins.SOLUTION: Provided is a composition for suppressing the accumulation of glycated proteins, the composition containing squalene as an active ingredient.SELECTED DRAWING: None

A compound of formula (I) [MCL-1 ligand moiety]-[linker]-[ligase ligand moiety](I) or a salt, solvate, hydrate, isomer or prodrug thereof, wherein [MCL-1 ligand moiety] is a compound of Formula (A) or wherein [MCL-1 ligand moiety] is a compound of Formula (A1), (A2), (A3) or (A4):, and its use in the treatment of cancer.

A process for preparing active polypeptide for promoting calcium absorption through multi-enzyme synergistic directional enzymolysis of egg yolk protein comprises the following steps: (1) raw material pretreatment: adopting degreased-lecithin-removed egg yolk powder as a raw material, and eliminating steric hindrance of lipid to enzymolysis; (2) double-enzyme synergistic enzymolysis: compounding neutral protease and trypsin according to a mass ratio of 2: (0.9-1.1), and carrying out synchronous enzymolysis for 2.5-3.5 hours under the conditions that the total enzyme amount is 2.25% (w / w), the temperature is 53-63 DEG C and the pH is 6.5-7.5; (3) separation: filtering the enzymatic hydrolysate through a plate frame, controlling the aperture to be 0.22-0.45 mu m, the gradient pressure to be 0.2-0.4 MPa and the temperature to be 55-60 DEG C, and then separating the filtrate through a 5kDa ultrafiltration membrane; and (4) concentrating and drying: concentrating the filtrate at low temperature until the solid content is 25-30%, and then performing spray drying to obtain yolk polypeptide powder with the polypeptide molecular weight being less than 5kDa and the proportion being more than 90%. The method has the technical effects of efficient directional enzymolysis, high product purity and strong calcium absorption promoting activity, and the egg yolk polypeptide powder with the polypeptide molecular weight being less than 5kDa and the proportion being more than 90% when the polypeptide molecular weight is more than 100Da is obtained.

The application discloses a photochemical chemiluminescence method for detecting myxovirus resistance protein A, and belongs to the technical field of marker detection. The application provides a detection system of the myxovirus resistance protein A, which comprises MxA Ab1-receptor microsphere complex and MxA Ab2-donor microsphere complex. The application provides the detection system of the myxovirus resistance protein A, which is used for the detection of MxA, is homogeneous and free of washing, simple in operation, high in sensitivity, and wide in linear range. The application is verified through experiments, and the detection limit of the myxovirus resistance protein A antigen is 1.37 ng / mL, and the linear range is 5-1229 ng / mL. The application is good in specificity and repeatability, can be used for rapidly detecting a virus infection marker, and has application value.

The present disclosure provides a polynucleotide encoding a protein having n repeats of a Protein A-derived domain, wherein the polynucleotide comprises n domain-encoding regions, each domain-encoding region differs from the other domain-encoding regions by at least five synonymous codons and n is at least three.

A method to make Co- or Ni-substituted protoporphyrin IX by incubating an E. coli strain in a rich medium containing iron ions and added Co2+ or Ni2+ ions, for a time and under conditions wherein the E. coli strain produces Co- or Ni-substituted protoporphyrin IX. The E. coli host may be transformed to contain and express a gene construct encoding a mutant EcHemH including a L13R mutation.

The invention relates to the technical field of detection, and discloses an immunochromatography test strip, a kit and application of the immunochromatography test strip, the immunochromatography test strip comprises a chromatography membrane, and a protein compound formed by mixing and incubating a recombinant protein A dimer and a capture antibody is fixed on a detection line of the chromatography membrane. The double-antibody sandwich immunochromatography detection method has the advantages that the high-efficiency capture of antigens is realized, the detection performance of double-antibody sandwich immunochromatography is enhanced, the sensitivity of the detection method can be improved, the implementation is simple and convenient, and the method can be applied to the development of the double-antibody sandwich immunochromatography method for various detection targets.

Provided herein are methods relating to the purification of a polypeptide comprising an Fc region (e.g., an antibody) via protein A chromatography; methods relating to the use of a wash solution comprising a benzoate salt and / or benzyl alcohol during protein A chromatography; and methods of adjusting a harvest using sodium benzoate prior to protein A chromatography.