58 results about "Phage display" patented technology

The invention discloses a preparation method and application of a cat main allergen FEL-1 nano antibody FEL-1-Nb, and relates to the technical field of antibody preparation, and the preparation method comprises the following steps: preparing an immunogen; animal immunization and library construction; constructing and panning a phage display library; screening and identifying positive clone; and expression and purification of the nano antibody: cloning the positively cloned VHH gene to an expression vector such as a pET series, transforming an expression strain such as escherichia coli BL21 (DE3), carrying out IPTG induced expression, and purifying through an inclusion body purification method to obtain a high-purity nano antibody protein. The nano antibody FEL-1-Nb provided by the invention can be specifically bound with a cat main allergen FEL-1 protein, the unique amino acid sequence of the nano antibody FEL-1-Nb is shown as SEQIDNO: 1, high-affinity binding with the FEL-1 protein is ensured, the positive clone binding rate is high through phage display panning and ELISA verification, the phage recovery rate after the third round of panning is increased by more than 1000 times compared with the first round of panning, and the positive clone binding rate is higher than that of the first round of panning. Therefore, the nano antibody has excellent targeted recognition capability.

This invention discloses a polypeptide that specifically binds to the coronavirus S protein, its encoding gene, and its applications, belonging to the field of molecular biology. The polypeptide specifically binding to the coronavirus S protein provided by this invention contains the following amino acid sequence: HFVKTPARWAWG, obtained through screening using phage display technology. The polypeptide provided by this invention can specifically bind to the coronavirus S protein and specifically block the binding of the coronavirus S protein to ACE2, thereby inhibiting coronavirus infection and can be used to prepare anti-coronavirus drugs.

The invention relates to the technical field of biology, and aims to provide an M13 recombinant bacteriophage with PRRSV broad-spectrum neutralizing activity for displaying NPC and application of the M13 recombinant bacteriophage. A nano antibody-CD163 peptide fragment conjugate NPC shown as SEQ ID NO: 1 is displayed on the surface of the N end of capsid protein III of the M13 recombinant phage, 1-3 NPC molecules are contained on the surface of each phage particle, and the phage is used for neutralizing PRRSV (Porcine Reproductive and Respiratory Syndrome Virus). The recombinant bacteriophage provided by the invention is easy to prepare, extremely high in virus titer and excellent in thermal and pH stability; in Marc-145 and PAMs cells, the compound shows strong neutralizing activity on PRRSV II type 1, 3, 5 and 8 pedigree, so that the compound has broad-spectrum neutralizing capacity; the compound can be used as a PRRSV prevention and control preparation, and a new thought is provided for development of safe and efficient novel antiviral drugs or biological preparations.

The invention belongs to the technical field of tumor immunotherapy, and relates to an anti-Claudin18.2 single-domain antibody, a multifunctional fusion protein, a recombinant natural killer cell (CT-CAR-NK), and preparation and application thereof. Through alpaca immunization and phage display library construction and panning, the single-domain antibody VHH-C18.2-1 specifically combined with Claudin18.2 is obtained, and the amino acid sequence of the single-domain antibody VHH-C18.2-1 is SEQ ID NO: 1. The amino acid sequence of the designed fusion protein is SEQ ID NO: 3, the fusion protein sequentially comprises a VHH-C18.2-1, a flexible Linker, a TGF-beta RII extracellular domain, a CD8alpha hinge region, a CD8alpha transmembrane region, a 4-1BB intracellular domain and a CD3zeta intracellular domain from the N end to the C end, and the fusion protein has the functions of targeting, resisting TGF-beta inhibition and activating signals. The fusion protein gene transfects human peripheral blood CD56 + CD3-NK cells through lentivirus to obtain CT-CAR-NK, in-vitro verification shows that the CT-CAR-NK still keeps efficient killing in an immunosuppression environment, tumor growth can be remarkably inhibited in vivo, the lifetime can be prolonged, and a safe and efficient scheme is provided for Claudin18.2 positive solid tumor treatment.

The invention belongs to the technical field of in-vitro diagnosis, and particularly relates to an anti-mycoplasma pneumoniae antibody, a mycoplasma pneumoniae detection quality control product and a preparation method and application of the mycoplasma pneumoniae antibody and the mycoplasma pneumoniae detection quality control product. The invention provides an anti-mycoplasma pneumoniae antibody which comprises a light chain variable region and a heavy chain variable region, and the light chain variable region and the heavy chain variable region are specifically combined with a C-terminal immunodominance region of mycoplasma pneumoniae P1 protein. Wherein the C-terminal repeat region of the mycoplasma pneumoniae P1 protein is a core immunogenicity region, has high conservative property and strong immunogenicity, can induce a host to generate a specific IgM antibody in the early stage of infection, and is an ideal antibody target. The anti-mycoplasma pneumoniae antibody is obtained by screening through a phage display technology, has high affinity and high specificity, can effectively recognize the C-terminal immunodominance region of the mycoplasma pneumoniae P1 protein, and provides a reliable detection tool for early diagnosis of mycoplasma pneumoniae.

The invention belongs to the technical field of biological pharmacy, and particularly discloses a Siglec-15 affinity peptide and application thereof. According to the invention, a phage display heptapeptide library high-throughput screening technology is adopted, Siglec-15 affinity peptide 7-8 is obtained through multiple rounds of screening, and the Siglec-15 affinity peptide 7-8 is optimized and modified to obtain a reversed sequence flip peptide d-7-8. Experimental results show that the Siglec-15 affinity peptide can be used for affinity of Siglec-15 protein and blocking the interaction between Siglec-15 and a ligand Sialyl-Tn of Siglec-15, so that the anti-tumor effect is achieved; an in-vitro cell level experiment shows that the Siglec-15 affinity peptide has a relieving effect on inhibition of Siglec-15 on CD8 + T cell proliferation, has an obvious immune activation effect, does not have obvious toxic or side effects, can be used for preparing an anti-tumor drug or a detection reagent taking Siglec-15 as a target spot, and has a relatively good medical application prospect.

The present application relates to a kind of artificially synthesized recombinant monoclonal antibody with human antibody amino acid sequence as framework.The present application uses phage display technology, and obtains one monoclonal antibody H11 from Tomlinson I+J phage library, and these new amino acid sequences constitute CDR1, CDR2 and CDR3 region, can be combined with A29L protein specific binding.It shows good stability, high specificity and high affinity and other characteristics, provide tool support for subsequent monkeypox virus diagnosis and detection with A29L protein as target.

The invention discloses a cat parvovirus VP2 protein nano antibody as well as a preparation method and application thereof, and belongs to the technical field of biological medicines. The amino acid sequence of the cat parvovirus VP2 protein nano antibody is as shown in SEQ ID NO. 1 or SEQ ID NO. 2. According to the invention, an alpaca is immunized by using FPV VP2 protein, a phage display nano antibody library is constructed, and two nano antibodies 3D6 and 1B9 with strong specificity and high affinity are obtained through multiple rounds of panning and identification. Through identification, the nano antibodies 3D6 and 1B9 can be specifically combined with FPV and VP2 proteins, and have high affinity and remarkable virus neutralizing activity. The nano antibody can be used for preparing a detection reagent or kit for feline parvovirus infection, and rapid and accurate diagnosis is realized; the compound can also be used as an active component to prepare a therapeutic drug, and provides a special therapeutic scheme for FPV infection. The nano antibody provides an important material basis for developing a novel diagnostic tool and a specific therapeutic drug aiming at the feline parvovirus.

This invention discloses nanobodies against rabies virus G protein and their applications, belonging to the field of nanobody technology. The nanobodies are antibody 11G6, antibody 9F7, or antibody 9A3; the amino acid sequence of antibody 11G6 is shown in SEQ ID NO. 8; the amino acid sequence of antibody 9F7 is shown in SEQ ID NO. 13; and the amino acid sequence of antibody 9A3 is shown in SEQ ID NO. 18. This invention uses phage display technology to screen for nanobodies with high affinity and high neutralizing activity. Based on this, this invention utilizes the advantage of the small size of nanobodies and verifies their unique ability to cross the blood-brain barrier (BBB) ​​through Transwell experiments, overcoming the limitation that large molecules such as antibodies and drugs cannot cross the BBB to enter the brain. This invention provides a new drug option for the treatment of rabies virus and has significant clinical implications.

The invention discloses a screening method and application of a shark-derived anti-idiotypic nano antibody, and belongs to the technical field of biological pharmacy and vaccines. The screening method comprises the following steps: immunizing adult shark by using a target pathogen specific antigen, collecting peripheral blood, separating lymphocytes, extracting RNA (Ribonucleic Acid), carrying out reverse transcription to synthesize cDNA (Complementary Deoxyribonucleic Acid), amplifying a nano antibody variable region fragment of a shark IgNAR (Immunoglobulin Nucleic Acid Receptor) gene, and constructing a phage display gene bank of which the storage capacity is greater than or equal to 1 * 10 < 8 > CFU and the recombination rate is greater than or equal to 85%; a variable region of a target pathogen specific antibody is taken as a target, specific bacteriophage is enriched through 3-4 rounds of gradient washing and elutriation (Tween-20 concentration and washing time are gradually improved), and the shark source anti-idiotypic nano antibody with high affinity and high purity (greater than or equal to 95%) is obtained by combining ELISA screening positive clone, gene sequencing de-weighting and SPR detection (combining dissociation constant KDlt, 1 * 10 <-7 > mol / L).

The present invention relates to the technical field of molecular biology, and in particular, to an anti-CD40 nanobody, and a preparation method therefor and use thereof. The anti-CD40 nanobody provided by the present invention has three unique complementarity determining regions, namely CDR1, CDR2, and CDR3. The present invention further provides a sequence encoding the nanobody or its VHH chain, a corresponding expression vector, and a host cell capable of expressing the nanobody. The present invention includes immunizing an alpaca by constructing a CD40 antigen to obtain a PBMC of the alpaca and constructing a vector; screening an anti-CD40 antibody through phage display; and finally obtaining a highly sensitive and specifically binding antibody through functional assays and sequencing result analysis. The nanobody provided by the present invention can specifically recognize and bind to CD40.

The present application relates to the technical field of antibody, in particular to a recombinant dopamine rabbit monoclonal antibody and application. The present application utilizes phage display technology and alanine scanning mutagenesis technology, and screens to obtain a dopamine monoclonal antibody, compared with other antibodies and the antibody without alanine scanning mutagenesis, the affinity and specificity are strong, the detection sensitivity is high, and the consistency with the antigen detection concentration result in liquid quality is high. The antibody is used for the detection of dopamine in serum, and the test result shows that the detection sensitivity is high, the specificity is good, the repeatability is high, the stability is good, the precision is high, and the antibody has an important role for the clinical diagnosis of dopamine.

The invention discloses a nano antibody targeting human cardiac troponin I and application of the nano antibody. According to the invention, through construction of a nano-antibody phage library and a phage screening technology, four nano-antibodies targeting human cardiac troponin I and having a good pairing effect are obtained. Compared with the traditional monoclonal antibody, the bacteriophage display nano antibody has the advantages of small size, high stability, simplicity and convenience in preparation, low cost, large-scale production and the like; the probe can be used as a core detection element and is applied to the field of diagnosis of clinical rapid detection of human cardiac troponin I.

Single-domain monoclonal antibodies that specifically bind B7H3 (also known as CD276) are described. The single-domain antibodies include camel VHH and rabbit VH domain nanobodies selected from phage display libraries. Chimeric antigen receptors (CARs) and other antibody conjugates targeted to B7H3 are also described. The single-domain antibodies and conjugates thereof can be used for the diagnosis and treatment of B7H3 expressing solid tumors.

This invention relates to the field of biomedical technology, specifically to a snake-derived nanobody against KLH and its preparation and application. The invention involves immunizing the black-browed rat snake with KLH, extracting total RNA from its splenic lymphocytes, constructing a phage display VH gene library, and, after multiple rounds of screening, obtaining nanobody sequences that specifically bind to KLH, such as KLH-1 and KLH-2. This nanobody can be efficiently and solublely expressed and purified in *E. coli*, exhibiting characteristics of small molecular weight and high affinity. This invention further provides applications for this nanobody, particularly in the preparation of KLH-targeting detection reagents or drug delivery systems. This nanobody provides a core tool molecule for developing highly sensitive KLH-targeting detection reagents, efficient drug delivery systems, and novel vaccines.

The present invention relates to antibodies having specificity to HER4 and uses thereof, which are able to induce biased 4ICD routing / signaling. The inventors have isolated by antibody phage display three fully human anti-HER4 single-chain variable antibody fragment (scFv), selected on human HER4 extracellular domain, referred as C6 mAb, D5 mAb and F4 mAb and one fully human anti-HER4 scFv named H2 mAb, selected on NRG 1β1-stimulated EGFR / HER4 JMaCYT1-transfected NIH3T3 cells. In particular, the present invention relates to an isolated anti-HER4 antibody, wherein said antibody binds to an epitope of the HER4 protein.

Described herein are TIGIT binding peptides, nanoparticle systems such as dendrimer systems including the TIGIT binding peptides, pharmaceutical formulations, and methods of use. Also described are methods of identifying peptides that bind a target receptor, the method including phage display, chemical synthesis, determination of binding affinities, and computational modeling. Advantageously, adaptive evolution modeling can be used to optimize the peptides identified in the methods for improved binding affinities.

The present application relates to the technical field of biology, and particularly discloses a kind of tyrosine iodination modified PP2A protein monoclonal antibody, preparation method and application.The present application is prepared by tyrosine iodination modified PP2A protein antigen peptide, rabbit is immunized to prepare monoclonal antibody, and is selected by phage display technology, expression vector amplification and ELISA screening, finally obtains a strain of monoclonal antibody R004 that can effectively recognize target.The antibody shows good sensitivity and specificity in immunohistochemistry, cell immunofluorescence and protein immunoblotting.The monoclonal antibody screened in the present application can be used in the detection of tyrosine iodination modification of PP2A protein catalytic subunit 307, and provides support for tumor diagnosis, anti-tumor and neurological disease drug research and development.

The invention belongs to the technical field of immunity and molecular biology, and relates to a phage display shark source single-domain antibody targeting areca phytoplasma and application of the phage display shark source single-domain antibody. The amino acid sequence of the phage display shark source single-domain antibody is shown as any one of SEQ ID NO.1-SEQ ID NO.2. The phage display shark source single-domain antibody is small in molecular weight, easy to modify and capable of deeply recognizing hidden antigen sites, and the phage display shark source single-domain antibody can be applied to the field of areca phytoplasma. The areca phytoplasma immunodominant membrane protein has high stability, and has high affinity and specificity to the areca phytoplasma immunodominant membrane protein. The phage display shark source single domain antibody provided by the invention can be used for detecting areca phytoplasma, has the advantages of rapid detection, high sensitivity, low interference, high stability and quantitative detection, and can realize on-site rapid detection while realizing detection of trace level phytoplasma immune dominant membrane protein in areca.

The application belongs to the technical field of biotechnology, and particularly relates to an anti-TL1A nanobody and application thereof. The amino acid sequences of the complementarity determining regions CDR1, CDR2 and CDR3 of the nanobody are respectively shown as SEQ ID NO:3, SEQ ID NO:4 and SEQ ID NO:5, and the amino acid sequence of the heavy chain variable region is shown as SEQ ID NO:1. The application uses a llama natural nanobody library and combines phage display technology to successfully screen a high-affinity nanobody targeting TL1A. The antibody can specifically recognize human TL1A protein and a TL1A overexpression cell line, and has high affinity, high specificity and good physicochemical stability. Based on the characteristic of targeting TL1A, the nanobody has important application value in the precise diagnosis and targeted treatment of TL1A high-expression related diseases such as inflammatory bowel disease, rheumatoid arthritis, asthma and fibrosis, and is particularly suitable for developing a high-sensitivity in-vitro diagnostic kit and a novel biological therapeutic drug.

The application discloses a kind of magnetic capture material based on phage display, preparation method and application thereof, through the synergistic effect of specific capture and short-time proliferation, the detection limit of staphylococcus aureus is improved to 10 4 CFU / mL, reaches the detection limit of portable ATP bioluminescence instrument itself, ensures the reliability of detection result. At the same time, the whole detection process can be completed within 1 hour, only needs simple equipment such as magnetic separation frame and portable ATP detector, easy to operate, fast, suitable for food safety on-site detection, medical institution environment monitoring and various scenes. In addition, compared with traditional antibody, phage-derived binding polypeptide can be produced in large quantities by microbial fermentation, with lower cost and better batch consistency, and the directional display strategy based on T4 capsid avoids the activity loss caused by chemical coupling, further improves the stability of reagent, and has good application and promotion prospect.

The present invention provides nanobodies targeting cadherin‑17 and uses thereof. The amino acid sequences of the complementarity-determining regions (CDRs) of the nanobodies targeting cadherin‑17 comprise a CDR1 shown in any one of SEQ ID NOs: 21-32, a CDR2 shown in any one of SEQ ID NOs: 34-45, and a CDR3 shown in any one of SEQ ID NOs: 47-58. In the present invention, an alpaca immune phage display library was constructed, a series of nanobody molecules targeting cadherin‑17 were obtained by screening the library, and the functions and uses of the nanobodies were validated at multiple levels, including the CDH17 antigen protein level, the CDH17 target cell level, and the CDH17 CAR‑T cell level.

The invention discloses an amino acid sequence of adipose-derived stem cell affinity polypeptide, a screening method and application of the adipose-derived stem cell affinity polypeptide. The amino acid sequence of the adipose-derived stem cell affinity polypeptide provided by the invention is KMISTIS. In the invention, the inventor screens out the affinity peptide aiming at the human ADSC by utilizing a phage display technology, and aims to improve the implantation efficiency of the ADSC in tissue engineering. The peptide is capable of binding to the surface of an acellular fat matrix (DAM), thereby recruiting endogenous ADSC.

This invention discloses an anti-CD5 protein nanobody and its applications, relating to the field of nanobody biosynthesis technology. Utilizing a camel-derived nanobody library and targeting mouse CD5 protein, this invention employs phage display technology for in vitro enrichment and panning. Camel-derived nanobody sequences targeting CD5 protein are obtained through monoclonal high-throughput ELISA screening. These five nanobody sequences can be used to detect CD5 protein expression, for the diagnosis and screening of related tumors, and also for the preparation of drugs to treat related tumors.

The invention discloses a preparation method of an anti-LSDV (Link Solution Department Virus) neutralizing nano antibody. Experiments prove that the structure of the nano-antibody with neutralizing activity is obtained by constructing a nano-antibody phage display library and screening the anti-LSDV nano-antibody based on the nano-antibody phage display library, and the specific structure of the nano-antibody is as shown in SEQ.ID.NO.4, SEQ.ID.NO.9 or SEQ.ID.NO.14. The invention also discloses a preparation method of the nano-antibody with neutralizing activity.

The invention discloses a high-affinity HER2 targeting polycyclic peptide molecule and a preparation method and application thereof.The preparation method comprises the steps that affinity optimization is conducted on initial HER2 targeting polycyclic peptides obtained through phage display library screening by combining a yeast display technology with an error-prone PCR directed evolution system, and a series of high-affinity disulfide bond-rich polycyclic peptides (DDMP) are obtained; the polycyclic peptide is coupled with a conjugate (DOTA or FITC) and a linker, so that a monovalent or divalent molecular probe can be constructed; the molecular probe has high specificity, high stability and good biocompatibility, can be used for accurate imaging and quantitative evaluation of HER2 positive cells / tumors and diagnosis and targeted therapy of HER2 signal path related diseases through radionuclide labeling or fluorescence labeling, and provides a novel tool and a transformation basis for early diagnosis and accurate treatment of HER2 positive solid tumors.

The application belongs to the technical field of animal vaccine preparation, and discloses an African swine fever virus (ASFV) multi-epitope fusion protein, a ferritin nanoparticle vaccine of the ASFV multi-epitope fusion protein and application. The application obtains 16 dominant B cell epitopes by using an ASFV phage display library in combination with reverse screening of clinical positive serum, and constructs a nanoparticle vaccine by linking the 16 epitopes with ferritin self-assembly. The vaccine has excellent biosafety, can induce high-level and sustained specific antibodies and significant IFN-gamma cellular immune response in pigs, can effectively delay the clinical onset and death process of pigs in ASFV virulent challenge experiments, and can significantly reduce the virus load in whole-body organ tissues, thereby providing 25% survival protection rate. The application provides an effective new strategy for the development of a subunit vaccine for responding to various ASFV mutant strains.

The invention relates to an anti-BCMA nano antibody and application thereof, and belongs to the technical field of biology. The anti-BCMA nano antibody comprises a heavy chain variable region which comprises three complementary determining regions CDR1, CDR2 and CDR3, and the amino acid sequence of the heavy chain variable region is SEQ ID NO: 1. The nanometer antibody targeting BCMA is obtained through an alpaca nanometer antibody natural library and a phage display technology, the antibody can specifically recognize Human BCMA recombinant protein and HEK293 hBCMA overexpression cells, and the nanometer antibody can be used for treating or diagnosing various inflammatory diseases and autoimmune diseases which are characterized by abnormal activation of BCMA signals. In particular to BCMA high-expression related malignant tumors such as multiple myeloma, the BCMA high-expression related malignant tumors show good application prospects and development potential.

The invention belongs to the field of molecular biology and immunology, and particularly relates to an anti-CD3 nano antibody capable of activating the activity of T cells as well as a preparation method and application of the anti-CD3 nano antibody. The invention provides a preparation method of the anti-CD3 nano antibody. The preparation method comprises the following steps: constructing a CD3 plasmid and an overexpression cell line, and immunizing alpaca to obtain peripheral blood mononuclear cells (PBMC) of the alpaca; extracting RNA (Ribonucleic Acid) and carrying out reverse transcription to obtain cDNA; carrying out PCR amplification on the antibody gene segment and cloning the antibody gene segment to a phage display vector; and electrically transforming the vector into SS320 competent cells to obtain the nano antibody library. After two rounds of panning, detecting and screening an antibody clone capable of being combined with the CD3 protein through ELISA (Enzyme-Linked Immunosorbent Assay); an antibody sequence is selected through sequencing, and an antibody protein is expressed by using a mammalian cell high-throughput expression system; and then detecting and screening the antibody which is only specifically combined with the CD3. The method disclosed by the invention is simple, convenient and rapid to operate, and can be used for preparing active antibodies for treating potential tumors and proliferative diseases.

The application discloses a fluorescent protein probe for noninvasive detection of myocardial cells and application thereof, and belongs to the field of protein and gene engineering. The application obtains an affinity peptide for myocardial cells by using a phage display dodecapeptide library, combines the affinity peptide with EGFP, and then is transferred into an expression vector, so that the expression is realized by using an E. coli expression system to obtain the fluorescent protein probe. The fluorescent protein probe can be used for detecting myocardial cells, real-time myocardial cell level detection is realized, and the defects and barriers existing in traditional detection methods are broken.