39 results about "Phage Display Techniques" patented technology

The invention belongs to the technical field of immunodetection, and discloses a preparation and characterization method of a rabbit-derived single-chain antibody for detecting a liver cancer marker GPC3. The rabbit-derived single-chain antibody has the characteristics of small volume, high specificity, high stability and good sensitivity, and can be used in an immunoassay method for detecting a liver cancer marker GPC3; according to the method, a specific rabbit single-chain antibody is obtained through screening, expression and purification by using a phage display technology, a GPC3 antigen is coated on a solid-phase carrier, the rabbit single-chain antibody is used as a detection carrier, the binding force of the single-chain antibody and the antigen is identified, and the method is high in specificity, good in sensitivity and high in specificity. A novel single-chain antibody with high specificity and high sensitivity is provided for detection of GPC3 in serum.

This invention belongs to the field of microcystin-LR detection technology, providing anti-microcystin-LR nanobodies and their applications. The anti-microcystin-LR nanobodies have amino acid sequences as shown in SEQ ID NO.1, SEQ ID NO.2, or SEQ ID NO.3. This invention uses phage display technology to screen for nanobodies with high affinity and high specificity for recognizing microcystin-LR, exhibiting advantages such as strong stability and ease of large-scale expression. Various detection tools can be designed based on anti-microcystin-LR, including test strips, immunoassay kits, immunoaffinity columns, biosensor detection chips, or detection probes. This provides novel antibody resources for rapid monitoring of microcystin-LR and lays a material foundation for developing low-cost, high-performance immunoassay technologies, which is of great significance for promoting the monitoring and control of microcystin-LR pollution.

The invention discloses a human-derived hysteromyoma targeting peptide and application thereof, the sequence of the targeting peptide is selected from SEQ ID NO: 1 to SEQ ID NO: 5, and the SEQ ID NO: 1 (VN12) is the most preferable. The fusion protein is obtained by screening through a phage display technology, and has high hysteromyoma targeting specificity and low immunogenicity. The targeting peptide can be coupled with nuclide or fluorescent dye, and is used for accurate PET imaging, fluorescent diagnosis and intraoperative navigation of hysteromyoma. Experiments prove that the molecular marker is specifically enriched in tumor tissues (the tumor / muscle ratio is 60), the biological safety is good, the problems of insufficient diagnosis sensitivity and large treatment wound in the prior art are solved, and the molecular marker has a great application prospect in diagnosis and treatment of hysteromyoma.

The application belongs to the technical field of biological medicine, and discloses a cyclic peptide molecule specifically targeting CD5 and purposes thereof. The surface receptor CD5 of immune cells (T cells, B cells) has been proved to be a potential tumor treatment target, the present application uses the phage display technology widely applied to the development of polypeptide or antibody drugs to carry out multiple rounds of in vitro screening on human CD5 protein, and obtains a cyclic peptide molecule with drug potential and capable of specifically combining with CD5 through second-generation sequencing. The cyclic peptide molecule contains two cysteines, is modified into a ring through a specific chemical crosslinking agent, and the affinity of the cyclic peptide molecule to CD5 is determined to be in the low micromolar level through surface plasmon resonance technology, thereby laying a foundation for the development of a CD5-targeting inhibitor.

The present invention discloses an intestinal microbiota Bacteroides fragilis toxin-neutralizing nanobody and its application. By deeply studying the enterotoxigenic Bacteroides fragilis and the toxin BFT secreted by it in the bodies of patients with colorectal cancer and breast cancer, nanobodies against BFT are expressed by phage display technology; nanobodies with high binding affinity to the antigen are screened out through biopanning technology; a nanobody with the ability to neutralize the toxicity of BFT, also known as Nb2.43, is obtained. The present invention expresses and optimizes to obtain a BFT nanobody protein with high affinity, stability and uniformity, opening up a new field for the treatment of colorectal cancer and breast cancer with nanobodies targeting BFT, and having good research value and application prospects.

The application relates to the technical field of biological medicine, and provides an anti-GPC3 full humanization single-domain antibody and application thereof. The application uses phage display technology to obtain one anti-human GPC3 specificity full humanization monoclonal single-domain antibody through antibody screening by targeting human GPC3 protein. The obtained single-domain antibody can be specifically combined with human GPC3, and can effectively inhibit the nuclear translocation of YAP, provides an effective alternative antibody drug for GPC3-targeted HCC treatment, and has a potential clinical application prospect.

The application belongs to the field of biological medicine, and provides an antibody combined with a specific antigen peptide of common pemphigus and application thereof, and the application uses the principle of phage display technology to perform in-vitro affinity screening on a constructed library, combines phages with target antigen Dsg3, elutes non-specific binders, retains phages combined with the antigen closely, and then amplifies the phages and performs multiple rounds of affinity enrichment; multiple rounds of panning are performed, and after 3-5 rounds of screening, phage clones with strong Dsg3 binding capacity and high specificity can be obtained.

The invention belongs to the technical field of biological medicines, and particularly relates to an anti-CD22 nano antibody as well as a preparation method and application thereof. The anti-CD22 nano antibody comprises a framework region and a complementarity determining region, wherein the complementarity determining region comprises CDR1 (SEQ ID NO: 1), CDR2 (SEQ ID NO: 2) and CDR3 (SEQ ID NO: 3). The preparation method comprises the following steps: immunizing alpaca by using Human CD22 / His protein, extracting RNA (Ribonucleic Acid) from PBMC (Peripheral Blood Mononuclear Cell) and reversely transcribing into cDNA (Complementary Deoxyribose Nucleic Acid), constructing a phage display library, then performing CD22 antigen protein elutriation to obtain positive clone, and after sequencing analysis, expressing the antibody by using a mammalian cell expression system. The optimized phage display technology is adopted, the screening period is short, and the obtained nano antibody is small in molecular weight, stable in structure and high in affinity to CD22. The antibody can be efficiently expressed through mammalian cells, and natural modification activity is reserved.

This invention provides an anti-trimethoprim single-chain antibody for detecting trimethoprim-like drug residues, its preparation method, and its application. The amino acid sequences of the single-chain antibody are shown in SEQ ID3, SEQ ID4, and SEQ ID6. Compared with traditional monoclonal antibodies, the single-chain antibody has lower production costs, is simpler to prepare, and is easier to manipulate at the gene level. This invention utilizes trimethoprim-specific monoclonal hybridoma cells and employs phage display technology to screen for high-affinity single-chain antibodies. A single-chain antibody mutant with even higher affinity was successfully obtained through computer simulation combined with site-directed mutagenesis. Based on this mutant, an ic-ELISA was established for the detection of trimethoprim residues in animal-derived foods, meeting the needs of practical applications.

The present application relates to the field of biotechnology, in particular to a kind of hyaluronidase binding cyclic peptide, the cyclic peptide is obtained by screening phage display technology, its structure includes X 1(n) CX3X4X5X6X7X8X9X 10 CX 12(m) It has the efficacy of inhibiting hyaluronidase activity, higher transdermal absorption capacity and / or anti-inflammatory, can be used as hyaluronidase (especially PH20) inhibitor, applied in the fields of medicine, food and cosmetics.

The invention belongs to the field of biological medicine, and provides an antibody combined with pemphigus vulgaris specific antigen peptide and application of the antibody. According to the principle of a phage display technology, a constructed library is subjected to in-vitro affinity screening, phages are combined with a target antigen Dsg3, non-specific binders are eluted, the phages tightly combined with the antigen are reserved, and the pemphigus vulgaris specific antigen peptide is obtained. Then, amplifying and carrying out affinity enrichment for multiple rounds; and carrying out multiple rounds of panning, and after 3-5 rounds of screening, obtaining phage clones with strong binding capacity with Dsg3 and high specificity.

The application belongs to the technical field of bioengineering, and relates to a fluorescent probe for detecting neuron-specific enolase and application. The application screens a specific binding short peptide E for neuron-specific enolase by using phage display technology, inserts a circular fluorescent protein R-GECO1 into the short peptide E, divides the E peptide chain into two parts E1 and E2, and forms a probe structure in the form of E1-R-GECO1-E2. The fluorescent probe protein provided by the application has relatively small molecular weight and is easy to mature, has large fluorescence dynamic change, has good specificity, and can detect neuron-specific enolase in and outside cells.

The invention belongs to the technical field of nano-antibodies, and particularly relates to a nano-antibody for resisting H1N1 influenza virus NA protein as well as a preparation method and application of the nano-antibody. The method comprises the following steps: by taking A / Puerto Rick / 8 / 34 (H1N1) influenza virus as a research object, purifying and inactivating the influenza virus through sucrose density gradient centrifugation, immunizing alpaca by taking the influenza virus as an immunogen, and screening by utilizing a phage display technology to obtain a high-affinity spectral anti-avian influenza virus NA protein nano antibody. Animal experiments show that the nano antibody has a good prevention effect when acting on A / Puerto Radio / 8 / 34 (H1N1) influenza virus infected C57 mice. Through preparation of the anti-influenza virus NA protein nano antibody, not only is a material provided for development of an H1N1 influenza virus diagnostic reagent, but also a thought is provided for identification of H1N1 subtype influenza virus epitope and vaccine design.

The invention relates to the technical field of biology, and discloses a nano antibody targeting a porcine deltacoronavirus (RBD) and application of the nano antibody. Two high-specificity nano antibodies VHH1 and VHH2 for resisting the porcine deltacoronavirus S protein RBD are obtained by screening through a phage display technology and have good reaction activity and neutralizing activity, and a sandwich ELISA detection method based on the nano antibodies is established. The method is high in sensitivity, strong in specificity and good in repeatability, the lowest detection limit is 25 ng / mL, the PDCoV S protein RBD antigen can be rapidly and accurately detected, and the method is suitable for rapid detection and epidemiological monitoring of PDCoV. The invention provides a new technical means for prevention and control of the PDCoV.

The present application relates to the technical field of medicine, and specifically, a peptide capable of specifically binding to ovary-specific protein-inhibin alpha protein (INHA, alpha-inhibin) is obtained through phage display technology, the peptide is anchored on the surface of human umbilical cord mesenchymal stem cells through the method of click chemistry, and then a preparation of umbilical cord mesenchymal stem cells is prepared. The peptide in the preparation of umbilical cord mesenchymal stem cells of the present application serves as a bridge and is applied to the targeted treatment of ovary-related diseases by anchoring the ovary organ.

The application belongs to the technical field of biological medicine, and particularly relates to an anti-CD22 nanobody and a preparation method and application thereof. The anti-CD22 nanobody comprises a framework region and a complementarity determining region, wherein the complementarity determining region comprises CDR1 (SEQ ID NO: 1), CDR2 (SEQ ID NO: 2) and CDR3 (SEQ ID NO: 3). The preparation method comprises the following steps: immunizing a llama with a Human CD22 / His protein, extracting RNA from PBMC cells and reverse transcribing the RNA into cDNA, constructing a phage display library, obtaining a positive clone through CD22 antigen protein panning after sequencing analysis, and expressing the antibody through a mammalian cell expression system. The application adopts an optimized phage display technology, has a short screening cycle, and the obtained nanobody has a small molecular weight, a stable structure and high affinity to CD22. The antibody can be efficiently expressed through a mammalian cell, and retains natural modification activity.

The invention relates to an anti-CD30 nano antibody as well as a preparation method and application thereof. The anti-CD30 nano antibody is obtained through a phage display technology. The method disclosed by the invention is simple and quick to operate; and a mammalian cell expression system induces high-efficiency expression of the antibody, and the activity of the antibody is closer to that of a natural antibody. The anti-CD30 nano antibody which is specifically combined with the Human CD30 is obtained through enzyme-linked immuno sorbent assay (ELISA) and FACS detection.

The invention relates to the technical field of biological medicine, in particular to a lung targeting peptide and application thereof in preparation of an extracellular vesicle drug delivery system. The amino acid sequence of the lung targeting peptide provided by the invention is as shown in SEQ ID NO. 2. The lung targeting peptide with alveolar epithelium targeting property is obtained through a phage display technology, the lung targeting peptide is combined to the surface of mesenchymal stem cell-derived extracellular vesicles (EVs), and the prepared targeting delivery system can act on lung epithelial cells more accurately and more long-acting, so that effective repair and protection of a lung barrier are realized. The invention provides an effective targeted delivery strategy for precise treatment of lung diseases, and has a good application prospect.

The invention belongs to the field of biological pharmacy, and particularly relates to a polypeptide G9 specifically targeting human ovarian cancer cells and application of the polypeptide G9. Aiming at the problems that the existing polypeptide targeting ovarian cancer is insufficient in targeting in in-vivo tumor cells and polypeptide with better in-vivo targeting needs to be developed, the invention provides the polypeptide G9 specifically targeting human ovarian cancer cells, which is obtained by screening through a phage display technology, and the amino acid sequence is shown as SEQ ID NO: 1. The polypeptide G9 disclosed by the invention can realize a targeted affinity effect on SKOV3 human ovarian cancer cells, and in a SKOV3 human ovarian cancer tumor-bearing mouse body, the polypeptide disclosed by the invention can realize specific affinity on ovarian cancer tumor tissues so as to achieve a targeted delivery effect. The targeting polypeptide provided by the invention has strong specificity and high targeting property, and has good application potential in the fields of early diagnosis and treatment of tumors and targeted therapy.

The invention discloses a method for targeted blocking of antibiotic resistance gene horizontal transfer based on replication-defective engineering bacteriophage and application, and belongs to the technical field of environmental microbiology and gene engineering. In order to solve the problems of ARGs release caused by a splitting strategy and biosafety risk of the engineering bacteriophage, the replication-defective engineering bacteriophage obtained by packaging a CRISPR-Cas9 system with a targeted cleavage resistance gene through a packaging system related to a bacteriophage display technology can reduce the risk of drug-resistant gene diffusion in an environment and a medical scene. The method has the main advantages that: 1) dual specificity: the method has the recognition capability of phage on specific host phenotype and the specific recognition of CRISPR-Cas9 on ARGs sequence, and dual precise targeting is realized; 2) the biosafety is high: after the element is delivered, the element cannot be copied in a host, the exogenous DNA is easily degraded by the host, and the residue and unexpected evolution of the engineering bacteriophage in the environment are avoided;

The present disclosure relates to a peptide binding to Trop 2 and a use thereof, wherein, in an attempt to find a peptide having an ability of specifically binding to Trop 2, a peptide (amino acid sequence: CSTLNVESC (SEQ ID NO: 1)) that selectively binds to Trop 2 was discovered using a phage display technique. Targeting cancers that are highly resistant to anticancer drugs in breast cancer (in particular, triple-negative breast cancer), pancreatic cancer, and cholangiocarcinoma while having no effective treatments, an effective anticancer drug may be prepared by delivering cancer-specific drugs or developing targeted therapeutic agents using the peptide of the present disclosure.

The invention relates to the technical field of biological medicine, in particular to a lysosome targeting chimeric molecule based on IGF2R-D11 structural domain targeting polypeptide and application of the lysosome targeting chimeric molecule. A novel polypeptide capable of being specifically combined with an insulin-like growth factor 2 receptor is obtained by screening through a phage display technology, the polypeptide is used as a key component and is fused with a targeting antibody through a genetic engineering method, and a bifunctional chimeric molecule capable of efficiently internalizing and mediating target protein targeting lysosome is constructed. A new technical platform is provided for the field of targeted protein degradation, and the method has important application value in the fields of tumor immunotherapy, autoimmune diseases and the like.

The invention provides an anti-MERS nano antibody, a nano antibody fusion protein and application thereof, and belongs to the technical field of antibody drugs, the anti-MERS nano antibody comprises amino acid sequences of CDR1, CDR2 and CDR3 regions: CDR1: GSIFSRYT, CDR2: GSIFSRYT, CDR3: GSIFSRYT, GSIFSRYT: GSIFSRYT: GSIFSRYT: GSIFSRYT: CDR2 is an ITSEGNT (Intermediate Transcription Enhanced And CDR3 is NAGGGGAYFYHGAS. The nano antibody is obtained by screening through a phage display technology and has a unique CDR partition, and an antigen recognition epitope of the nano antibody is located in an RBD region of S1 protein. The anti-MERS nano antibody fusion protein provided by the invention has the characteristics of high expression, high stability, high specificity, high affinity, low immunogenicity and low-cost large-scale production, is suitable for industrial production, is expected to be used for coping with MERS pandemic potential crisis, and has great application value.

According to the CGRP and SP antibodies and the application thereof in virus infection resistance, CGRP polypeptide and SP polypeptide are optimized and combined respectively, the expression quantity and immunogenicity are greatly improved, the optimal CGRP and SP monoclonal antibodies are screened out through a phage display technology, the optimal antibodies are high in affinity and specificity, and the monoclonal antibodies can be used for resisting virus infection. When the polypeptide is used in combination, the polypeptide shows extremely high capability of resisting DNA / RNA virus infection in a synergistic manner, the expression of macrophage interferon and the expression of inflammatory factors are remarkably improved, and the polypeptide has important clinical application value.

Provided is a use of an antibody having nuclear RNA export factor 2 in the preparation of drugs for treating hepatocellular carcinoma. For nuclear RNA export factor 2, a single-chain antibody having high affinity and specificity for the nuclear RNA export factor 2 is prepared by using phage display technology, and the single-chain antibody can be used for preparing a detection reagent for the nuclear RNA export factor 2. In addition, treatment of a hepatocellular carcinoma mouse model using the single-chain antibody has shown that the single-chain antibody can effectively enhance the activity of immune cells in the tumor microenvironment, significantly increase the number of CD8+ T cells inside the tumor, and significantly inhibit the growth of the tumor.

Neuroendocrine tumors (NETs) are a class of highly heterogeneous tumors derived from neuroendocrine cells. Synaptic vesicle 2 (SV2) protein is a novel marker of NETs, and there are three subtypes of SV2A, SV2B and SV2C, wherein the structure of SV2C is more stable than the other two, and the largest cavity ring L4 thereof is the most important binding area with toxins. The present application obtains a nanobody of the extracellular soluble part L4 of SV2 by screening through phage display technology, and the nanobody labeled with a fluorescein, a small molecule of a chemical toxin or a nuclide is used to prepare a probe molecule, and the result can be specifically combined with neuroendocrine tumor cells. The present application provides a nanobody of the extracellular soluble part L4 of SV2, and the nanobody can be applied in the preparation of diagnostic and therapeutic preparations for neuroendocrine tumors.

The application belongs to the technical field of protein, and discloses a short peptide specifically combined with carcinoembryonic antigen and application. The carcinoembryonic antigen is a broad-spectrum tumor marker, and has important clinical value in tumor screening, monitoring, diagnosis and efficacy evaluation. The application relates to a method for obtaining a short peptide C2 of the carcinoembryonic antigen by phage display technology. The amino acid sequence of the short peptide C2 is shown as SEQ ID NO. 1. The specific short peptide screened by the application has the characteristics of small relative molecular mass, good stability and high affinity, and plays an important role in tumor molecular diagnosis and early screening. The specific short peptide can be used for designing a probe for detecting the carcinoembryonic antigen, and can also be used for developing a targeted therapeutic drug.

The invention belongs to the technical field of polypeptide library construction, and particularly relates to a method for constructing a thiazole polypeptide library based on a phage display technology. The method comprises the following steps: firstly, introducing a thiazole group on a polypeptide chain by using thiazole synthetase, and determining the sequence preference of the enzyme through a model peptide so as to guide library design; and integrating a gene for coding the enzyme into a host bacterium genome by utilizing CRISPR-Cas9, and constructing a stably expressed chassis cell. Carrying out PCR (Polymerase Chain Reaction) amplification on a phage vector, carrying out NotI enzyme digestion and T4 connection to construct a DNA (Deoxyribose Nucleic Acid) library, and electrically transforming the DNA library to a chassis cell to obtain a phage library for displaying the thiazole modified polypeptide. The phage display of the skeleton modified polypeptide is realized for the first time, the structural diversity of the phage display polypeptide is obviously expanded by introducing the thiazole group with unique physicochemical properties, the polypeptide stability and membrane permeability are improved, and a new technical platform is provided for screening of high-affinity polypeptide and development of druggability lead compounds.

This invention belongs to the field of biomedical technology and discloses a fully human antibody against human INHBA, a method for developing such an antibody, and its applications. The amino acid sequence of the light chain of the fully human antibody against human INHBA is shown in SEQ ID No. 1, and the amino acid sequence of its heavy chain is shown in SEQ ID No. 2. All antibodies obtained in this invention are fully human INHBA antibodies. The final screened antibody #6 can inhibit tumor proliferation and improve the therapeutic effect of gemcitabine on pancreatic cancer. This invention uses phage display technology to develop a fully human antibody that can target INHBA, avoiding immune responses caused by immunogenicity, providing a new method for the treatment of pancreatic cancer. Targeting INHBA enhances the chemotherapeutic effect of gemcitabine on pancreatic cancer tumors.

The application belongs to the technical field of biological medicine, and particularly relates to an anti-B7H3 nanobody and application thereof. The existing antibody against B7H3 is mainly a mouse monoclonal antibody, which has the problems of large molecular weight, poor tissue penetration, and difficulty in engineering modification, and the application provides an anti-B7H3 nanobody and application thereof. The application takes a human B7H3 target as an antigen, and 15 anti-B7H3 specific nanobodies are screened through phage display technology, which can specifically bind to the B7H3 antigen, have high specificity and high affinity, and have the advantages of small molecular weight, high stability, easy modification, and strong solubility. Meanwhile, the anti-B7H3 nanobody is connected with an anti-CD3 antibody OKT3 scFv to prepare a B7H3 / CD3 bispecific antibody, and in-vivo and in-vitro experiments show that the B7H3 / CD3 bispecific antibody has good antitumor effect, and the B7H3 / CD3 bispecific antibody can be applied to the preparation of an antitumor drug and has a wide antitumor effect.