30 results about "Antibody variable region" patented technology

Novel multispecific antigen-binding molecules maintaining excellent cellular cytotoxicity and high stability, which comprise a domain that contains an antibody variable region having glypican 3-binding activity and a domain that contains an antibody variable region having T-cell receptor complex-binding activity, were discovered. Since the molecules of the present invention show a strong cytotoxicity against cells and tissues expressing glypican 3, it is possible to produce novel pharmaceutical compositions for treating or preventing various cancers.

The present disclosure provides editable cell lines, including the use of gene editing proteins to produce the cell lines. The editable cell lines are able to express antibody constant regions that can serve as a platform for the antibody variable regions to produce customized antibody.

The application provides a nanobody targeting human transmembrane activator and calcium modulator and cyclophilin interactor (TACI) and an application thereof, and the antibody is derived from a llama heavy chain antibody variable region. The anti-TACI single-domain antibody NB38 can specifically bind to human TACI with high affinity, can recognize a recombinant TACI protein, can also recognize a TACI with a natural conformation on a cell surface, and can partially block a BAFF / APRIL signal pathway. Based on the nanobody, the application constructs a fusion protein, a chimeric antigen receptor, an effector cell expressing the chimeric antigen receptor, and a double-specific cell linker and other genetically engineered forms. The nanobody can be further extended into a drug coupling form. The product of the application can be used for mediating directional recognition and killing of TACI positive cells, and can be used as a supplement and expansion of BCMA targeted therapy, and provides a new candidate technical scheme for targeted therapy of multiple myeloma and other TACI related diseases.

The present invention provides the preparation, epitope identification and application of a PRRSV non-structural protein 12 antibody. By constructing a eukaryotic expression vector pCDNA3.4-Nsp12-strep, transiently transfecting CHO cells, and purifying the PRRSV Nsp12 recombinant protein using the downstream strep tag, the purified Nsp12 is used as an antigen to immunize Balb / C mice. The spleen cells of the mice are isolated, and single specific B cells are separated by the FACS method. The antibody variable region sequences of the single B cells are obtained by RT-PCR. Recombinant expression plasmids of the heavy chain and light chain are constructed respectively, transfected into CHO suspension cells, expressed, and 2 complete anti-PRRSV Nsp12 monoclonal antibodies 1N14 and 2S18 are obtained by Protein G purification. The application scopes of the 1N14 and 2S18 antibodies and the specific antigen epitope recognized by the 1N14 antibody are further determined, and its sequence is 104 YEFTGNGEDW 113 。

The present disclosure provides an immunogenicity prediction method for antibody drug development. According to the immunogenicity prediction method provided by the invention, based on an antibody variable region amino acid sequence, an embedded layer output by an encoder in a ProtT5-XL-UniRef 50 pre-training model is used as a sequence feature, principal component analysis (PCA) is used for carrying out dimensionality reduction on the extracted feature to obtain a final feature, AutoGluon is adopted for integrating a plurality of sub-models, and a final model is obtained through training. The high / low immunogenicity of the antibody can be predicted by using the trained model and the extracted features, and the antibody drug with low immunogenicity can be a better choice for clinical development through prediction.

The application discloses a targeting superantigen fusion protein based on an improved SE(3)-Transformer and an implementation method. In an offline stage, amino acid sequences are first converted into one-hot encoding or language model embedding (such as ESM-2), and are spliced with multiple sequence alignment (MSA) features for geometric initialization. A neural network (improved SE(3)-Transformer) combined with multiple sequence alignment (MSA) and an attention mechanism is constructed to predict the coordinates of C alpha, C, N and O atoms for main chain prediction, and the neural network is trained through a gradient descent method based on a physical heuristic potential item. In a verification stage, the improved SE(3)-Transformer after training is used to generate a predicted structure, conformational stability is verified through a simplified force field, and fine tuning is performed based on a confidence score. The application can accurately predict the structure of a target antigen epitope and an antibody variable region, optimize a superantigen functional domain in combination with a graph neural network, and dynamically design a flexible connecting peptide to realize modular fusion.

The invention discloses a preparation method of a p-tau231 monoclonal antibody, the p-tau231 monoclonal antibody and an antibody variable region, and relates to the technical field of antibodies, the preparation method comprises the following steps: polypeptide design and synthesis: designing and synthesizing a phosphorylated polypeptide and a non-phosphorylated control polypeptide based on the 224th-238th amino acid sequence of tau protein, the phosphorylated polypeptide sequence is CKKVAVVRT (p) PPKSPSS, the phosphorylated polypeptide sequence is CKKVAVVRT (p) PPKSPSS, the phosphorylated polypeptide sequence is CKKVAVVRT (p) PPKSPSS, and the non-phosphorylated control polypeptide sequence is CKKVAVVRT (p) PPKSPSS; threonine (Thr231) at the 231st site is subjected to phosphorylation; the sequence of the non-phosphorylated polypeptide is CKKVAVVRTPPKSPSS, and the sequence of the non-phosphorylated polypeptide is Immunogen coupling: introducing cysteine residues to the N end of the phosphorylated polypeptide, and connecting the phosphorylated polypeptide with carrier protein KLH through a sulfydryl chemical coupling method to form an immunogen compound; and preparation of the conjugate for detection: introducing cysteine residues to the N ends of the phosphorylated polypeptide and the non-phosphorylated polypeptide, and respectively coupling with a carrier protein BSA to form the antigen complex for detection. The p-tau231 monoclonal antibody prepared by the technical scheme of the invention can be specifically combined with a p-tau231 antigen, has no specific reaction with non-phosphorylated polypeptide and tau polypeptide, and can be applied to early diagnosis of AD (Alzheimer's disease).

The invention relates to the technical field of gene engineering, and particularly discloses a one-step RT-PCR (Reverse Transcription-Polymerase Chain Reaction) kit for amplifying a complete sequence of a variable region of a rabbit-derived antibody and a use method of the one-step RT-PCR kit. The kit comprises an One-Step RT Enzyme Mix, a 5 * One-Step RT Buffer, three pairs of specific amplification primers, a positive control, a negative control and a Nuclease-free Water, and is characterized in that the specific amplification primers are used for amplification of the Nuclease-free Water, and the specific amplification primers are used for amplification of the Nuclease-free Water. The three pairs of primers are designed according to rabbit immune globulin gene sequences and can fully cover heavy chain and light chain variable regions. The use method comprises the following steps: sorting positive B cells from rabbit spleen, cracking single cells, continuously performing reverse transcription and PCR (Polymerase Chain Reaction) amplification in the same reaction system by taking a cracking product as a template, and identifying and cloning the product. The kit can efficiently and specifically obtain the complete sequence of the variable region of the rabbit antibody from the single B cell, and has the advantages of wide coverage, high sensitivity, simplicity and convenience in operation and reliable result.

To provide antigen-binding domains binding to CD3 and CD137 and methods of using the same, and also provide methods to obtain antigen binding domains which bind to two or more different antigens more efficiently.SOLUTION: The present invention provides antigen-binding molecules, comprising: an antibody variable region that is capable of binding to CD3 and CD137, but does not bind to CD3 and CD137 at the same time; and a variable region binding to a third antigen different from CD3 and CD137.SELECTED DRAWING: Figure 1

Herein is reported a method for selecting a variant of a parental antibody variable domain encoding nucleic acid, wherein the parental antibody variable domain amino acid sequence encoded by said encoding nucleic acid has at least one developability hot spot, the method comprising the steps of (i) providing a multitude of DNA-containing samples (genomic material of antibody secreting B-cell) each including one or more antibody variable domain encoding nucleic acids; (ii) performing PCR amplification of said antibody variable domain encoding nucleic acids of (i) using consensus sequence-specific primers to obtain amplification products (wherein said consensus sequence-specific primers bind to consensus sequences that are common to a plurality of genes within the genetic loci set, thereby generating a pool of amplification products); (iii) sequencing a plurality of said amplification products obtained in step (ii) in order to determine the relative proportion of each nucleotide at each position in a sequencing read; (iv) performing a sequence alignment between the sequencing read results of (iii) and the parental antibody variable domain encoding nucleic acid; (v) performing a sequence-identity / homology-based ranking of the antibody variable domain encoding nucleic acids in said sequence alignment with the parental antibody variable domain encoding nucleic acid being the perfect / template / reference sequence; and (vi) selecting the variant antibody variable domain encoding nucleic acid based on the sequence ranking of step (v), whereby the variant selected in step (vi) is selected so that the developability hot-spot is removed.

The application relates to the fields of biological medicine and antibody engineering technology, and particularly relates to a STAT3 hybridoma-derived antibody affinity maturation method based on computational biology, which comprises the following steps: (1) obtaining an antibody variable region sequence; (2) constructing STAT3 antigen and antibody models and evaluating; (3) performing antigen-antibody molecular docking and optimization, and screening out models; (4) performing docking model analysis, and obtaining potential saturation mutation sites; (5) performing site saturation mutation, and obtaining mutation results; (6) performing mutation site analysis, and determining final mutation sites; (7) amplifying a target fragment containing the mutation sites; (8) constructing a recombinant expression vector, and obtaining a reformed STAT3 recombinant antibody through eukaryotic expression and purification; and (9) performing relative affinity determination.

A method for promoting diversification of variable regions of an antibody, particularly a method for promoting diversification of the amino acid sequences of variable regions of an antibody generated by an avian B cell population, the method including suppressing the PI3Kα activity of each avian B cell comprised in the avian B cell population expressing the antibody.

The present disclosure provides editable cell lines, including the use of gene editing proteins to produce these cell lines, which are capable of expressing antibody constant regions that can serve as platforms for antibody variable regions to produce customized antibodies.

The problem to be solved by the present invention is to provide an antibody, preferably a bispecific or multispecific antibody, for the treatment of tumors.SOLUTION: The present invention relates to antigen-binding proteins that bind to human CD3, wherein the heavy chain variable region comprises the following amino acid sequences: CDR1: SFGISCDR2: GFIPVLGTANYAQKFQGCDR3: RGNWNPFDP or the amino acid sequences: CDR1: SX1TFTIS, CDR2: GIIPX2FGTITYAQKFQG, CDR3: RGNWNPFDP, wherein = K or R and = L or I. The present invention relates to antigen-binding proteins that bind to human, wherein the heavy chain variable region comprises the following amino acid sequences:::: RGNWNPFDP or the amino acid sequences: = K or R and = L or I. The present invention relates to antigen-binding proteins that bind to human. X1 CDR3 X2 CDR2 CDR1.SELECTED DRAWING: None

The invention provides a nano antibody targeting human transmembrane activator and calmodulin TACI (transmembrane activator and calmodulin phosphatase) interaction protein and application of the nano antibody. The antibody is derived from an alpaca heavy-chain antibody variable region. The anti-TACI single-domain antibody NB38 can be combined with human TACI with high affinity and specificity, can recognize recombinant TACI protein, can also recognize TACI with native conformation on the surface of a cell, and can partially block a BAFF / APRIL signal channel. Based on the nano antibody, gene engineering forms such as fusion protein, a chimeric antigen receptor, effector cells for expressing the chimeric antigen receptor, a bispecific cell connector and the like are constructed. The nano antibody can be further expanded into a coupled drug form. The product can be used for mediating directional recognition and killing of TACI positive cells, can be used as supplement and expansion of BCMA targeted therapy, and provides a new candidate technical scheme for targeted therapy of multiple myeloma and other TACI related diseases.

The present disclosure provides a mutant of an antibody, and use thereof. Specifically, according to the Kabat numbering system, the mutant of the antibody has an engineered cysteine residue at any one or more position(s) selected from: positions 12, 34, 35, 38, 44, 47, 51, 60, 61, 67, 69, 78, 79, and 114 of the heavy chain variable region, or any combination thereof, or positions 19, 21, 44, 46, 47, 48, 62, 71, 75, 78, and 87 of the light chain variable region, or any combination thereof. The sulfhydryl group on the engineered cysteine can remain partially active in the antibody expression process. The active sulfhydryl group can be directly used to react with other active groups without reduction treatment. The cysteine-engineered antibody of the present disclosure can obtain the active groups for conjugating a drug, which is conducive to simplifying the production process of the antibody-drug conjugates, improving the homogeneity of the antibody-drug conjugates, increasing the efficacy, and reducing the toxicity and side effects.

The invention relates to the field of artificial intelligence, and particularly discloses an antibody variable region structure prediction method based on structure prior evaluation, which comprises the following steps: S1, screening a high-resolution and high-integrity compound containing a complete antigen and an antibody H / L chain from PDB, and extracting atomic coordinates after processing; s2, calculating geometrical characteristics of a molecular structure and relative spherical polar coordinates of adjacent residues; s3, calculating a structure quality evaluation score according to physical prior and a dihedral angle-atomic spacing mapping formula; s4, screening training data according to scores, and removing low-quality data; s5, constructing an antigen-antibody attribute isomeric graph and initializing a compound graph; s6, embedding related data as enhanced features when the model is initialized; s7, loading an RA-EGN encoder to output a CDR sequence and a 3D coordinate, and splicing a complete antibody structure; and S8, introducing a structure prior loss function fine tuning model, and performing multi-index screening on an optimal result. According to the invention, the problems of low prediction precision and insufficient structure prior utilization of the existing antibody CDR region are solved, and the prediction accuracy of the antibody variable region is improved.

The invention provides an anti-canine PD-L1 monoclonal antibody or an antigen binding fragment thereof and an application of the anti-canine PD-L1 monoclonal antibody or the antigen binding fragment. A heavy chain variable region and a light chain variable region of the anti-canine PD-L1 monoclonal antibody or the antigen binding fragment of the anti-canine PD-L1 monoclonal antibody comprise amino acid sequences as shown in SEQ ID NO.1-6. The anti-canine PD-L1 monoclonal antibody is formed by assembling a murine antibody variable region and a murine antibody constant region sequence, and has biological binding activity with canine PD-L1 protein, so that the anti-canine PD-L1 gene engineering monoclonal antibody provided by the invention can provide a basis for modification and development of canine antibodies, and can be used for preparing the anti-canine PD-L1 gene engineering monoclonal antibody. The compound can play a role in treating canine tumors or canine autoimmune diseases.

The present inventors have successfully prepared a library consisting essentially of a plurality of antigen-binding molecules differing in sequence from each other, the antigen-binding molecules each comprising an antibody variable region that has binding activity against a first antigen and a second antigen different from the first antigen, but does not bind to the first antigen and the second antigen at the same time. Use of the library of the present invention allows the obtainment of a variable region having enhanced ability to bind to the first antigen and the production of a bispecific antibody against the first antigen and a cancer antigen. Moreover, the present inventors have also successfully prepared an antigen-binding molecule comprising an antibody variable region that has binding activity against three different antigens, but does not bind to these antigens at the same time.

The invention discloses an antibody variable region design method and system based on an electron density generation model, constructs a set of complete process for integrating electron density information into antibody variable region design, and more accurately reduces the conformation of an antibody-antigen compound by introducing molecular dynamics simulation. Generating a series of electron densities of antibody variable regions CDR by using a protein generation model based on the electron densities, and realizing higher structure generation quality through deep mining of original structure information; and a structure prediction model and a high-precision combined free energy calculation method are used to review and screen the generated structure, so that the practicability and success rate of the generated result are improved. Finally, through optional process iteration, the success rate of antibody design is further improved; the development cycle of the high-performance therapeutic antibody is expected to be remarkably shortened, the research and development cost is reduced, and a powerful solution is provided for various dependent antibody treatment methods.

Provided are an anti-CLL1 antibody and an application thereof. An anti-CLL1 antibody variable region comprises CDRs of SEQ ID NO: 1-6, SEQ ID NO: 5, and SEQ ID NO: 7-11, or SEQ ID NO: 12-17. The anti-

The present inventors have successfully prepared an antigen-binding molecule comprising an antibody variable region that has binding activity against a molecule expressed on the surface of a T cell and a molecule expressed on the surface of any other immunocyte, but does not bind to these molecules at the same time. The present invention allows the preparation of an antigen-binding molecule capable of circumventing adverse reactions that may be caused by the cross-linking of T cells to other immunocytes, and provides an antigen-binding molecule suitable as a drug.

The present inventors have successfully prepared a library consisting essentially of a plurality of antigen-binding molecules differing in sequence from each other, the antigen-binding molecules each comprising an antibody variable region that has binding activity against a first antigen and a second antigen different from the first antigen, but does not bind to the first antigen and the second antigen at the same time. Use of the library of the present invention allows the obtainment of a variable region having enhanced ability to bind to the first antigen and the production of a bispecific antibody against the first antigen and a cancer antigen. Moreover, the present inventors have also successfully prepared an antigen-binding molecule comprising an antibody variable region that has binding activity against three different antigens, but does not bind to these antigens at the same time.

The invention relates to an antibody variable region sequencing method based on a top-down proteomics technology. The antibody variable region sequencing method is mainly characterized in that a multi-charge selective ion scanning strategy, an ultraviolet light dissociation mass spectrometry technology and a map integration algorithm are integrated. The method comprises the following steps: carrying out enzymolysis on an antibody to obtain three subunits, carrying out liquid chromatography separation, carrying out electrospray ionization to enter a mass spectrum, carrying out high-efficiency excitation and dissociation on the three subunits by adopting ultraviolet laser to generate fragment ions, finally detecting the fragment ions by adopting the mass spectrum, and obtaining a high-quality antibody subunit mass spectrum dissociation spectrum by adopting a spectrum integration and average algorithm. And finally, performing complete sequence coverage sequencing by utilizing complementarity of fragments in different charge states. According to the method provided by the invention, the amino acid sequence and post-translational modification of the antibody can be accurately identified, the coverage rate of the antibody sequence is greatly improved, and complete sequencing of the variable region of the antibody is realized.

The invention belongs to the technical field of gene engineering antibody preparation, and particularly relates to a primer group and a kit for amplifying a variable region gene of a monkey-derived antibody and a preparation method of the monkey-derived antibody, the primer group comprises one or more of the following (1)-(3): (1) a primer pair for amplifying a gamma heavy chain variable region, the DNA sequence of which is as shown in SEQ ID NO.1-3; (2) a primer pair for amplifying a kappa light chain variable region, wherein the DNA sequence of the primer pair is shown as SEQ ID NO.4-6; and (3) a primer pair for amplifying the lambda light chain variable region, wherein the DNA sequence of the primer pair is as shown in SEQ ID NO.7-9. According to the primer group provided by the invention, naturally paired heavy chain and light chain variable region genes can be obtained through one-time PCR rapid amplification, and the primer group has the advantages of good variable region sequence diversity, high specificity, high amplification efficiency, high accuracy and the like.

The present inventors have successfully prepared an antigen-binding molecule comprising an antibody variable region that has binding activity against a molecule expressed on the surface of a T cell and a molecule expressed on the surface of any other immunocyte, but does not bind to these molecules at the same time. The present invention allows the preparation of an antigen-binding molecule capable of circumventing adverse reactions that may be caused by the cross-linking of T cells to other immunocytes, and provides an antigen-binding molecule suitable as a drug.

The present invention provides variants of antibodies and their use. Specifically, based on the Kabat numbering system, the variants of the antibodies have cysteine residues engineered at any one or more positions selected from the following: positions 12, 34, 35, 38, 44, 47, 51, 60, 61, 67, 69, 78, 79, 114 in the heavy chain variable region or any combination thereof, or positions 19, 21, 44, 46, 47, 48, 62, 71, 75, 78, 87 in the light chain variable region or any combination thereof. The mercapto groups of the engineered cysteines can maintain partial activity during and after antibody expression. The mercapto groups that maintain activity may be directly used for reaction with other active groups without undergoing a reduction treatment. The cysteine-engineered antibodies of the present invention can obtain active groups for drug binding, which is advantageous for simplifying the production process of antibody-drug conjugates, improving the uniformity of antibody-drug conjugates, enhancing drug efficacy, and reducing toxic side effects.

To provide antigen-binding molecules which exhibit effective target-specific cell killing efficacy mediated by immune cells (e.g. T cells) while having reduced or minimal side effects, and to provide a pharmaceutical composition comprising the antigen binding molecule, and a method for producing the antigen-binding molecule.SOLUTION: An antigen-binding molecule capable of binding to multiple different antigens (e.g., CD3 on T cells), but does not nonspecifically crosslink two or more immune cells such as T cells is provided. Such multispecific antigen-binding molecule is capable of modulating and / or activating an immune response while circumventing the cross-linking between different cells resulting from the binding of the conventional multispecific antigen-binding molecule to antigens expressed on the different cells, which is considered to be responsible for adverse reactions when the multispecific antigen-binding molecule is used as a drug.SELECTED DRAWING: None

The invention relates to the technical field of biology, and particularly discloses a method for rapidly screening a high-affinity shark source nano antibody based on a BACTH system. The method comprises the following steps: fusing an antigen and an adenylate cyclase T25 fragment on a pKT25c plasmid, fusing a shark source nano antibody variable region library and an adenylate cyclase T18 fragment on a pUT18tc plasmid, and co-transforming into adenylate cyclase defective escherichia coli BTH101. When the antigen interacts with the nano antibody, the reconstructed adenylate cyclase activates downstream lacZ and chloramphenicol resistance double reporter genes. A blue monoclonal clone with chloramphenicol resistance is screened on a flat plate containing X-Gal, IPTG and chloramphenicol at one time, so that a high-affinity positive clone can be quickly obtained. The method overcomes the defects that a phage display technology is tedious in process, long in period and high in false positive, the whole screening process only needs one week, and the method has the remarkable advantages of being efficient, simple, convenient and low in cost.