112 results about "Antibody Repertoire" patented technology

The present invention provides a structure-based methodology for efficiently generating and screening protein libraries for optimized proteins with desirable biological functions, such as antibodies with high binding affinity and low immunogenicity in humans. In one embodiment, a method is provided for constructing a library of antibody sequences based on a three dimensional structure of a lead antibody. The method comprises: providing an amino acid sequence of the variable region of the heavy chain (VH) or light chain (VL) of a lead antibody, the lead antibody having a known three dimensional structure which is defined as a lead structural template; identifying the amino acid sequences in the CDRs of the lead antibody; selecting one of the CDRs in the VH or VL region of the lead antibody; providing an amino acid sequence that comprises at least 3 consecutive amino acid residues in the selected CDR, the selected amino acid sequence being a lead sequence; comparing the lead sequence profile with a plurality of tester protein sequences; selecting from the plurality of tester protein sequences at least two peptide segments that have at least 10% sequence identity with lead sequence, the selected peptide segments forming a hit library; determining if a member of the hit library is structurally compatible with the lead structural template using a scoring function; and selecting the members of the hit library that score equal to or better than or equal to the lead sequence. The selected members of the hit library can be expressed in vitro or in vivo to produce a library of recombinant antibodies that can be screened for novel or improved function(s) over the lead antibody.

Compostions, kits and methods are provided for generating highly diverse libraries of proteins such as antibodies via homologous recombination in vivo, and screening these libraries against protein, peptide and nucleic acid targets using a two-hybrid method in yeast. The method for screening a library of tester proteins against a target protein or peptide comprises: expressing a library of tester proteins in yeast cells, each tester protein being a fusion protein comprised of a first polypeptide subunit whose sequence varies within the library, a second polypeptide subunit whose sequence varies within the library independently of the first polypeptide, and a linker peptide which links the first and second polypeptide subunits; expressing one or more target fusion proteins in the yeast cells expressing the tester proteins, each of the target fusion proteins comprising a target peptide or protein; and selecting those yeast cells in which a reporter gene is expressed, the expression of the reporter gene being activated by binding of the tester fusion protein to the target fusion protein.

Compositions, methods, and kits are provided for efficiently generating and screening a library of highly diverse protein complexes for their ability to bind to other proteins or oligonucleotide sequences. In one aspect of the invention, a library of expression vectors is provided for expressing the library of protein complexes. The library comprises a first nucleotide sequence encoding a first polypeptide subunit; and a second nucleotide sequence encoding a second polypeptide subunit. The first and second nucleotide sequences each independently varies within the library of expression vectors. In addition, the first and second polypeptide subunit are expressed as separate proteins which self-assemble to form a protein complex, such as a double-chain antibody fragment (dcFv or Fab) and a fully assembled antibody, in cells into which the library of expression vectors are introduced. The library of expression vectors can be efficiently generated in yeast cells through homologous recombination; and the encoded proteins complexes with high binding affinity to their target molecule can be selected by high throughput screening in vivo or in vitro.

The invention relates to novel humanized antibodies derived from the conventional antibody repertoire of species in the family Camelidae.

A genetically modified non-human animal is provided, wherein the non-human animal expresses an antibody repertoire capable of pH dependent binding to antigens upon immunization. A genetically modified non-human animal is provided that expresses human immunoglobulin light chain variable domains derived from a limited repertoire of human immunoglobulin light chain variable gene segments that comprise histidine modifications in their germline sequence. Methods of making non-human animals that express antibodies comprising histidine residues encoded by histidine codons introduced into immunoglobulin light chain nucleotide sequences are provided.

The present invention relates to compositions and methods for raising antibodies generally comprising 1) providing highly immunogenic vesicles bearing at least one target antigen and 2) immunizing animals with the said antigen-bearing vesicles to induce antigen-specific antibody responses. The invention also relates to methods of screening antibody repertoires comprising 1) providing vesicles bearing at least one target antigen and one marker and 2) isolating antibody-producing cells or particles with defined antigen specificity using the said antigen- and marker-bearing vesicles. Antibodies with defined antigen specificity can then be prepared from isolated antibody-producing cells using known methods of the art. This invention can be used in experimental, research, therapeutic, prophylactic or diagnostic areas.

The present invention relates to antibodies or antibody fragments that may be displayed on the extracellular surface of the plasma membrane when expressed in a host cell. The present invention provides libraries comprising a plurality of plasma membrane displayed antibodies and methods of screening the libraries for antibodies or antibody fragments with desired characteristics.

A genetically modified non-human animal is provided, wherein the non-human animal expresses an antibody repertoire capable of pH dependent binding to antigens upon immunization. A genetically modified non-human animal is provided that expresses a single light chain variable domain derived from a single rearranged light chain variable region gene in the germline of the non-human animal, wherein the single rearranged light chain variable region gene comprises a substitution of at least one non-histidine encoding codon with a histidine encoding codon. Methods of making non-human animals that express antibodies comprising a histidine-containing universal light chain are provided.

The invention relates to a platform technology for production of antigen binding polypeptides having specificity for a desired target antigen which is based on the conventional antibody repertoire of species in the family Camelidae, and to antigen binding polypeptides obtained using this technology platform. In particular, the invention provides an antigen binding polypeptide comprising a VH domain and a VL domain, wherein at least one hypervariable loop or complementarity determining region (CDR) in the VH domain or the VL domain is obtained from a VH or VL domain of a species in the family Camelidae.

Compostions, kits and methods are provided for generating highly diverse libraries of proteins such as antibodies via homologous recombination in vivo, and screening these libraries against protein, peptide and nucleic acid targets using a two-hybrid method in yeast. The method for screening a library of tester proteins against a target protein or peptide comprises: expressing a library of tester proteins in yeast cells, each tester protein being a fusion protein comprised of a first polypeptide subunit whose sequence varies within the library, a second polypeptide subunit whose sequence varies within the library independently of the first polypeptide, and a linker peptide which links the first and second polypeptide subunits; expressing one or more target fusion proteins in the yeast cells expressing the tester proteins, each of the target fusion proteins comprising a target peptide or protein; and selecting those yeast cells in which a reporter gene is expressed, the expression of the reporter gene being activated by binding of the tester fusion protein to the target fusion protein.

Provided are methods for efficiently and comprehensively screening antibody repertoires from B cells to obtain and produce molecules with binding characteristics and functional activities for use in human therapy.

The invention discloses a phage display antibody library and five strains of screened antibodies capable of being combined with S protein of novel coronavirus SARS-CoV-2. Mutation is introduced into an ultra-variable region of an antibody variable region based on synthetic biology and a phage display technology, and a gene is transferred into escherichia coli, so that a synthetic antibody librarycontaining 108 kinds of antibodies is constructed; the phage display antibody library provided by the invention can perform screening to obtain the antibody with the specificity and the detection function, so that powerful resources of biological research and medical diagnosis are expanded; and the five strains of antibodies capable of being combined with the S protein of the novel coronavirus arefurther screened out and can be used for detecting the virus, part of the antibodies can block combination of the virus and cells, and the antibodies have the capacity of neutralizing novel coronavirus infectivity, can be used for preparing a novel coronavirus detection product, preparing a drug for inhibiting the novel coronavirus and preparing a pharmaceutical preparation for preventing or treating diseases caused by the novel coronavirus, and have a wide application prospect.

The invention discloses a novel single-domain antibody resistant to human beta2-microglobulin as well as a preparation method and an application of the single-domain antibody. A phage display technology is adopted to perform multiple rounds of screening on an alpaca phage antibody library to obtain phage enriched with beta2-microglobulin specificity, the phage is cultured for preparing the antibody, positive clone is obtained through identification, a coding sequence corresponding to the positive clone is obtained through sequencing, and then expression is performed in escherichia coli to obtain a soluble antibody fragment. The antibody has an amino acid sequence represented as SEQ ID NO.1 or SEQ ID NO.10. The antibody provided by the invention has very high bonding capacity for beta2-microglobulin, can be applied to the fields of blood purification and beta2-microglobulin detection, and facilitates promotion and improvement of diagnosis and treatment for diseases such as dialysis-related amyloidosis and the like.

A phage display library of variable heavy domain (VHH or VH) fragments (sdAb fragments) derived from the antibody repertoire of a non-immunized llama is disclosed. The sdAb fragments of the library are characterized by the absence of cysteine residues in complementarity determining regions (CDRs) and a very low presence of residues of glutamic acid, arginine and glycine at positions 44, 45 and 47, respectively, of the VL interface of the variable heavy domain VHH. The large size of the library (in the order of 109) makes it a source of antigen-binding fragments having high affinity to almost any antigen of interest. The library is preferably generated using a modified fd-tet phage growing in plaques in the absence of a tetracycline.

The invention relates to a phage antibody library which assembles an ScFv gene fragment between Restriction Enzyme cutting sites of SfiI and NotI of a pCANTAB5E carrier. The phage antibody library is characterized in that the ScFv gene fragment can be affinitive and enriched with antigens of 16-membered macrolide agricultural chemicals to form a soluble single-chain antibody and the phage antibody library is applied to immunoassay of pesticide residue. The phage antibody library has the advantages that the antibody with high affinity can be obtained without animal immunization, the test period is short, the antibody library is the phage antibody library which takes small molecular milbemycin oxime of a 16-membered macrolide generic structure as immunogen to construct, the antibody library theoretically can directly obtain a specific antibody library of 16-membered macrolide compound through screening, the screening flux is high, the efficiency is high, the specificity is strong, and the affinity selecting range is wide, so that the phage antibody library has wide application prospect in the aspects such as agricultural chemical antibody preparation, testing technique development and the like.

The invention belongs to the field of antibody drug, and discloses a full human-derived anti-human VEGFR2 monoclonal antibody screened by a phage antibody base technology and prepared by a gene engineering method, and further discloses a carrier including polynucleotide for encoding the monoclonal antibody, a host cell and an application. Through combining with VEGFR2, the monoclonal antibody stops the combination of VEGF with VEGR2, and does not induce receptor dimerization, cause the following tyrosine residue phosphorylation in intracellular tyrosine kinase structure and activate downstream signal access including activation of phospholipase C and increase of calcium ion concentration in the cell and others; the antibody drug triggers endothelial proliferation, survival, cytoskeleton rearrangement, cell migration, gene expression and others, and finally stops the vascular proliferation caused by combination of VEGF and VEGFR2 and induction of dimerization. The monoclonal antibody can be used for treating diseases caused by tumor angiogenesis.

A phage display library of variable heavy domain (VHH or VH) fragments (sdAb fragments) derived from the antibody repertoire of a non-immunized llama is disclosed. The sdAb fragments of the library are characterized by the absence of cysteine residues in complementarity determining regions (CDRs) and a very low presence of residues of glutamic acid, arginine and glycine at positions 44, 45 and 47, respectively, of the VL interface of the variable heavy domain VHH. The large size of the library (in the order of 109) makes it a source of antigen-binding fragments having high affinity to almost any antigen of interest. The library is preferably generated using a modified fd-tet phage growing in plaques in the absence of a tetracycline.

The invention provides the technical field of antibody medicine, discloses a fully-humanized human anti-IL-1beta monoclonal antibody screened through the phage antibody library technology and prepared through the genetic engineering technology, and discloses a DNA molecule for encoding the monoclonal antibody, a DNA molecule expression carrier for encoding the monoclonal antibody, a host cell and application. The anti-IL-1beta monoclonal antibody can prevent bonding of human IL-1beta and human IL-1R. By means of bonding of IL-1beta, blocking of IL-1beta and a receptor signal channel of the IL-1beta, unnecessary IL-1beta initial induced heat transfer, amplified lymphocyte responses and stimulation acute stage responses can be reduced. The anti-IL-1beta monoclonal antibody can be used for detecting IL-1beta expressions and used for prevention and treatment of cryopyrin-associated periodic syndromes.

Provided herein are methods of isolating a polynucleotide encoding a polypeptide such as an antibody with a desired property by way of mammalian display library screening and methods of generating a library of polynucleotides encoding polypeptides such as antibodies, wherein the polynucleotides collectively encode at least 109 different polypeptides. Also provided are kits for carry out the methods described herein, polynucleotides isolated by methods described herein, libraries encoding the antibody reservoir of different species including human, mouse, rabbit, and polypeptides encoded by the polynucleotides.

The present invention describes transgenic animals with human(ized) immunoglobulin loci and transgenes encoding human(ized) Igα and / or Igβ sequences. Of particular interest are animals with transgenic heavy and light chain immunoglobulin loci capable of producing a diversified human(ized) antibody repertoire that have their endogenous production of Ig and / or endogenous Igα and / or Igβ sequences suppressed. Simultaneous expression of human(ized) immunoglobulin and human(ized) Igα and / or Igβ results in normal B-cell development, affinity maturation and efficient expression of human(ized) antibodies.

A process for preparing an antigen microarray based on self antibody repertoire includes pre-treating substrate for adapting molecular self-assembly, generating a layer of agarose gel moleculae, chemical modifying it, designing antigen microarray, preparing antigen microarray by applying different biomacromolecular antigens on the surface of said substrate, and testint the chip by use of microscope or fluorescent scan to acquire the information about specimen. Its test method includes culturing the said microarray chip and specimen to be tested in warmhouse, hybridization with the second antigen probe of three fluorescein labels, and acquiring the information about specimen by multi-channel fluorescent scan.

The invention provides antibody arrays specific for target antigens. Methods for discovery and compositions comprising native human antibodies, arrays comprising such antibodies, immortalized B cells expressing such antibodies and non-immortalized B cell libraries comprising B cells expressing such antibodies are provided. The invention provides a method for screening monoclonal antibodies for functional effects on cell surface molecules such as receptors using antibody repertoire arrays specific for target cell surface molecules. Functional antibodies directed to a target and therapeutics derived from such antibodies are also provided. High throughput and parallel screening for potentially therapeutic antibodies are provided. Antibodies directed to functional epitope clusters corresponding to a target and vaccines and therapeutics derived from such antibodies are also provided.

The invention discloses a complete humanized antibody which is selected from humanized high-capacity phage antibody library and is high-affinity-combined with phosphatidylinositol proteoglycan 3. The invention includes a selection method of the antibody, an antibody coding sequence and corresponding amino acid residue sequence, and especially includes three CDR-zone sequences respectively at a heavy chain and a light chain, combination characters of an antigen and the construction method of the complete antibody. The antibody is a complete humanized antibody, is used for treatment in human body, is low in immunogenicity, is less in toxic and side effects, and has a potential value of treating liver cancer and melanin tumor.