840 results about "Single chain" patented technology

The invention relates to the field of gene therapy, in particular to an RBM25 gene epigenetics activation technology based on a CRISPR / dCas9-SunTag system and application of the RBM25 gene epigenetics activation technology in ischemic heart failure treatment, the RBM25 gene epigenetics activation technology comprises the following steps: (a) protein containing inactivated Cas9 (dCas9) fused with a plurality of GCN4 peptide repetitive sequences, the number of the GCN4 peptide repetitive sequences is 8-12, and the dCas9 contains D10A and H840A double mutations; (b) a protein containing fusion of an anti-GCN4 single-chain antibody fragment (scFv) and a TET1 catalytic structural domain; (c) at least one gRNA of a target RBM25 gene promoter region, wherein a target sequence of the gRNA is selected from a sequence as shown in SEQ ID NO: 1-3; and (d) a lipid nanoparticle (LNP) system for delivery of said (a), (b), and (c).

The invention relates to a biological preparation for improving quality of weever, the biological preparation comprises an injection and an edible agent, the injection comprises chemically modified chemically synthesized single-stranded small RNA, Rev-erbalpha protein and Per1 protein, and the edible agent comprises Clock core peptide 1, Clock core peptide 2 and taurine. Skeletal muscle development, liver lipid metabolism and generation of cell inflammatory factors of the weever are influenced by adding and injecting the feed, so that the quality of the weever is improved, intramuscular fat deposition is promoted, the taste and flavor of fish meat are improved, the energy reserve of the weever can be improved, and the culture cycle is shortened. The improvement of cell inflammatory factors shows that the disease resistance of the weever is improved, the survival rate in the breeding process is further improved, and the use amount of antibiotics is reduced. The method provides an important theoretical basis for improving fish meat quality in China and promoting high-quality, efficient and healthy development of aquaculture, and has a wide market prospect.

The invention discloses preparation of a human CD56 immune phage display antibody library, which comprises the following steps: S1, animal immunization: expressing recombinant hCD56 protein in escherichia coli, then immunizing a Balb / c mouse, and detecting immune titer; s2, splenocyte preparation: extracting RNA (Ribonucleic Acid) of immune mouse spleen cells, and performing reverse transcription to obtain cDNA (Complementary Deoxyribonucleic Acid); s3, preparation of an initial bacteriophage display library: amplifying a heavy chain variable region and a light chain variable region by using a PCR technology, and then assembling to form scFv; constructing scFv phagocytids, electrically transforming the scFv phagocytids into TG1 competent cells, and constructing a bacterial library; s4, constructing a phage single-chain library of the hCD56: infecting the bacterial library by using a helper phage M13K07, and constructing a phage single-chain antibody library; and S5, elutriation and screening of a phage library: specifically enriching a phage single-chain antibody library, screening positive clones from the phage single-chain antibody library, and determining a sequence. According to the invention, the human hCD56 antibody scFv sequence fragment can be screened out, and the research and development period is shortened.

The invention discloses a recombinant fusion protein of a human lambda light-chain single-chain antibody, a DNA (deoxyribonucleic acid) molecule, a library building method and application, and the recombinant fusion protein of the human lambda light-chain single-chain antibody is the recombinant fusion protein formed by connecting the human lambda light-chain single-chain antibody, phage Piii protein and luciferase, the amino acid sequence of the recombinant fusion protein of the human lambda light-chain single-chain antibody is shown as SEQ ID NO: 5, the recombinant fusion protein library of the human lambda light-chain single-chain antibody has large capacity, the established single-chain antibody TG1 library is more than 1 * 10 < 9 > cfu / mL, positive clones capable of being combined with ligands can be screened and enriched for multiple rounds, and the recombinant fusion protein library has the characteristics of high sensitivity, high signal-to-noise ratio and the like.

The invention discloses a double-target chimeric antigen receptor for co-expression of CD47 and IL-15, a CAR-T cell and application of the CAR-T cell, and belongs to the technical field of genetic engineering, the double-target chimeric antigen receptor comprises a single-chain antibody scFv-EGFRv III, a single-chain antibody scFv-VEGF, CD47 and IL-15; the nucleotide artificial sequence of the single-chain antibody scFv-EGFRv III is as shown in SEQ ID NO. 6; the nucleotide artificial sequence of the single-chain antibody scFv-VEGF is as shown in SEQ ID NO. 9. According to the application disclosed by the invention, by performing sequence optimization on targets EGFRvIII and VEGF, the anti-tumor effect of CAR-T cells in glioblastoma can be improved, and by integrating immune checkpoint molecules CD47 and interleukin-15, the immunosuppression function of a CD47-SIRP alpha signal channel can be locally exerted.

The invention belongs to the technical field of biological medicine and molecular biology, and particularly relates to a single-chain antibody targeting NRP1, a CAR-T cell and application of the single-chain antibody and the CAR-T cell in fibrosis treatment. Four types of high-affinity single-chain antibodies targeting mouse NRP1 antigens are obtained by immunizing mice, the single-chain antibodies are applied to second-generation CAR, T cells of mouse spleen sources are infected after virus packaging, and CAR-T cells are constructed. The CAR-T cells of the targeted NRP1 can be used for effectively killing NRP1 positive cells. In-vivo experiments show that the CAR-T cells can inhibit the growth of NRP1 positive tumor cells. The CAR-T cell can improve the mouse liver fibrosis condition, collagen in the mouse liver is reduced through treatment, and the molecular level of fibrosis markers SMA and NRP1 is reduced, it is indicated that the CAR-T cell recognizes and eliminates activated HSCs through targeting NRP1, and the fibrosis degree is reduced.

Provided herein are chimeric receptors, including chimeric antigen receptors (CARs), comprising BCMA-binding molecules, including anti-BCMA antibodies and antigen-binding fragments thereof, including heavy chain variable (VH) regions and single-chain antibody fragments, and encoding polynucleotides. In some embodiments, the anti-BCMA chimeric receptors specifically bind to BCMA. Among the anti-BCMA-binding molecules are human antibodies, including those that compete for binding to BCMA with reference antibodies, including a non-human reference antibody. Also provided are genetically engineered cells expressing the CARs and uses thereof including in adoptive cell therapy.

Disclosed are a preparation method and application of a single-chain antibody fragment targeting SARS-COV-2 nucleocapsid protein, aiming to provide a single-chain antibody fragment with high affinity and strong specificity. The present disclosure obtains three single-chain antibody fragments targeting SARS-COV-2 nucleocapsid protein through construction of a nanobody phage library and phage screening technology. The single-chain antibody fragment consists of a heavy chain variable region, a 15aa connecting peptide, and a light chain variable region connected in sequence, and has an amino acid sequence shown in SEQ ID NO: 1-SEQ ID NO: 3. The single-chain antibody fragment in the present disclosure has excellent binding performance and specificity with the SARS-COV-2 nucleocapsid protein, can be applied to a variety of immunoassay platforms of the SARS-COV-2, and has broad application prospects in the field of SARS-COV-2 detection.

The invention provides a reagent for detecting avian leukosis virus, a nano-enzyme immunochromatography test strip and application of the nano-enzyme immunochromatography test strip, and belongs to the technical field of immunology. Aiming at the problems that the existing avian leukosis virus detection method is complicated in operation, time-consuming or strong in equipment dependence, the reagent comprises a capture antibody and a detection antibody; a heavy chain variable region of the monoclonal antibody A comprises an amino acid sequence as shown in SEQ ID NO: 1, and a light chain variable region of the monoclonal antibody A comprises an amino acid sequence as shown in SEQ ID NO: 2; a heavy chain variable region of the monoclonal antibody B comprises an amino acid sequence as shown in SEQ ID NO: 5, and a light chain variable region of the monoclonal antibody B comprises an amino acid sequence as shown in SEQ ID NO: 6; the antigen binding fragment is a Fab fragment, an F (ab) 2 fragment or a single-chain Fv fragment. The reagent is mainly used for detecting avian leukosis virus, and is suitable for detecting samples such as cloaca swab, meconium, egg white or serum of poultry.

Provided herein are antibodies and antibody fragments that bind to human TNFRSF25. The antibodies may be monoclonal and / or biparatopic antibodies and / or single- chain fragment variable (scFv) antibodies. Methods of treating or preventing diseases or disorders associated with inflammation and / or autoimmunity are provided, comprising administering to a patient in need thereof an effective amount of a human TNFRSF25- binding antibody.

This disclosure relates methods for expanding γδ T cells. More specifically, the disclosure relates to methods of expanding γδ T cells that have an eliminated or reduced expression of endogenous MHC Class I molecules, by expressing a single-chain fusion HLA Class I protein. In some embodiments, the endogenous B2M gene of the γδ T cells is disrupted. In some embodiments, the single-chain fusion HLA Class I protein includes at least a portion of B2M protein and at least a portion of HLA-E heavy chain.

The preparation and evaluation method comprises the following steps: 1, extracting a heavy-chain DNA fragment and a light-chain DNA fragment, carrying out recombinant transformation by using an overlapping PCR method to construct an scFv gene, 2, constructing an expression vector, culturing the expression vector, carrying out sequencing identification to obtain an scFv bacterial solution, recombining the scFv bacterial solution with a mouse Fc fragment, and identifying a sequence to obtain an MN8 bacterial solution, the method comprises the following steps: 1, preparing an MN8 bacterial liquid, 2, extracting the MN8 bacterial liquid, 3, carrying out inoculated culture on the MN8 bacterial liquid to obtain an MN8 genetically engineered antibody bacterial liquid, 4, extracting MN8 genetically engineered antibody bacterial liquid plasmids and carrying out transfection expression purification, and 5, carrying out antibody titer and thermal stability determination on the MN8 genetically engineered antibody. The scFv single-chain antibody obtained by recombination according to the method has the advantages of small molecular weight, high penetrability and the like, the stability and the sensitivity of an immunoassay method of the scolosporins can be improved, and a certain basis is provided for rapid determination of the scolosporins.

The invention belongs to the technical field of biomedical detection, and discloses a nucleic acid aptamer, a nucleic acid aptamer derivative and application thereof. An aptamer DNA long single chain targeting DLL3 is screened through an exponential enrichment systematic evolution (SELEX) technology, sequence optimization is performed on the aptamer DNA long single chain to obtain another two short chains, the aptamer can specifically target tumor cell surface DLL3, and the aptamer and small cell lung cancer cells SHP77, H69 and the like with high expression of the DLL3 have a specific targeting recognition effect. The invention also discloses screening and optimization of the nucleic acid aptamer. The nucleic acid aptamer has the advantages of being high in affinity and specificity, free of immunogenicity, simple and stable in chemical synthesis, easy to store and mark and the like.

The invention provides a compound for releasing a urine fluorescent biomarker under induction of mitochondrial DNA mutation as well as a preparation method and application of the compound, and belongs to the technical field of medicines. The compound disclosed by the invention is prepared by the following steps: complementarily pairing a hybrid nucleic acid nano-carrier containing single-stranded DNA (Deoxyribose Nucleic Acid), an annular fluorescent reporter molecule and a Cas12a / crRNA compound through bases of DNA or RNA, and then coating polyethyleneimine and hyaluronic acid. A CRISPR / Cas12a system is selected as a converter of tumor specific mitochondrial DNA mutation information and urine fluorescence signals, a nano delivery system which responds to mtDNA single base mutation and is used for tumor progress monitoring and early metastasis warning is designed and synthesized, and the nano delivery system has a good application prospect in tumor progress monitoring and early metastasis sensitive detection.

The invention relates to the technical field of gene engineering, in particular to application of wheat TaLNUE protein in regulation and control of low nitrogen stress tolerance of plants. According to the invention, a single-chain guide RNA of a target wheat TaLNUE gene is designed, an expression vector of the TaLNUE gene is knocked out, and the expression vector is transformed into wild type wheat, so that transgenic wheat with the function inhibited by the TaLNUE gene is obtained. Researches find that the spike length and the spikelet number of wheat under low nitrogen stress can be increased by inhibiting the expression of the wheat TaLNUE protein, so that the single plant yield and the total yield of the wheat under low nitrogen stress are increased, and the nitrogen absorption efficiency and the nitrogen utilization efficiency of the wheat under low nitrogen stress are improved. According to the technical scheme, a feasible method is provided for improving the wheat yield under low nitrogen stress by utilizing a genetic engineering technology.

The present invention is directed to a monoclonal anti-human CS1 clone 7A8D5 antibody or a single-chain variable fragment (scFv), comprising VH having the amino acid of SEQ ID NO: 4 and VL having the amino acid of SEQ ID NO: 5. The present invention is also directed to a chimeric antigen receptor fusion protein comprising from N-terminus to C-terminus: (i) CS1 scFv of the present invention, (ii) a transmembrane domain, (iii) at least one co-stimulatory domains, and (iv) an activating domain.

The present invention provides a combined chimeric antigen receptor targeting CD19 and CD20 and application thereof. Specifically, the present invention provides a combined chimeric antigen receptor targeting CD19 and CD20, which comprises a scFv targeting CD19 and CD20, a hinge region, a transmembrane region, and an intracellular signaling domain. The present invention provides a nucleic acid molecule encoding the chimeric antigen receptor and a corresponding expression vector, a CAR-T cell, and applications thereof. The experimental results show that the chimeric antigen receptor provided by the present invention shows extremely high killing ability against tumor cells. The chimeric antigen receptor of the present invention targets CD19 and / or CD20 positive cells and can be used to treat CD19 and / or CD20 positive B-cell lymphoma, leukemia and other diseases.

The invention belongs to the technical field of immunodetection, and discloses an avian single-chain antibody for detecting a liver cancer marker GPC3, a kit and a detection method. The poultry-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 chicken-derived single-chain antibody is coated on a solid-phase carrier, a rabbit-derived polyclonal antibody is taken as a detection carrier, the antibodies are combined with a GPC3 antigen to form a sandwich structure, and the double-antibody sandwich immunoassay method of the GPC3 is established by using the method, and has the advantages of high specificity, good sensitivity, high sensitivity and high sensitivity. The invention provides a rapid, accurate and reliable detection method for detecting GPC3 in serum.

The present disclosure relates to methods of detecting and / or quantifying one or more target nucleic acid molecules in a sample, comprising: a) contacting the sample with a reaction mix comprising: i) reagents for amplifying the target nucleic acid molecules; ii) an Argonaute (Ago) enzyme, one or more guide single stranded uncleic acid molecules, and one or more reporter nucleic acid molecules; and iii) a pyrophosphatase (PPase) for regenerating Mg2+ in the reaction mix; b) partitioning the mixture of the sample and the reaction mix into a plurality of compartments; c) amplifying the one or more target uncleic acid molecules in each compartment to obtain amplified target nucleic acid molecules; and d) detecting a signal in each compartment based on cleavage of the reporter nucleic acid molecules by the Ago enzyme in the presence of the amplified target nucleic acid molecules and guide single stranded nucleic acid molecules.

The invention discloses a chimeric antigen receptor modified cell drug as well as a preparation method and application thereof, and belongs to the technical field of cell drugs. A cell drug is obtained by introducing a chimeric antigen receptor targeting B cells and / or plasma cells into in-vitro or in-vivo immune cells through a gene delivery system, and target spots of the targeted B cells and / or plasma cells comprise CD19, BCMA, CD20, CD22, CD38, CD138, GPRC5D and SLAMF7. The chimeric antigen receptor modified cell drug can realize specific recognition of B cells and / or plasma cells and activate immune cells through a specific single-chain antibody fragment (scFv), and can specifically remove the B cells in vitro and in vivo, thereby preventing the generation of autoimmune antibodies and the formation of immune complexes, achieving the purpose of thoroughly treating diseases, and having good application prospects. The life quality of a patient is improved, the disease is finally cured, and the application potential and the commercial value are huge.

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.

The invention provides a glass nanopore probe based on an aptamer and application of the glass nanopore probe in dopamine detection, and belongs to the technical field of electrochemical sensing and scanning probe microscopy. The sensor comprises: a glass nanopore probe, the inner wall of which is modified with a gold layer; a cDNA (complementary deoxyribonucleic acid) single chain is fixed on the gold layer through a gold-sulfur bond; a part of the sequence of the dopamine aptamer is hybridized and combined with the cDNA single chain; wherein the combination of the dopamine and the dopamine aptamer causes the change of an ion current rectification signal of the glass nanopore probe, so that the detection of the dopamine is realized based on the change of the ion current rectification signal of the glass nanopore probe. The invention provides a valuable scheme for developing an aptamer nanopore scanning electrochemical sensor for single cell analysis and researching neurotransmitter-related diseases.

A protein cryoelectron microscope structure assembling method based on point cloud registration belongs to the field of bioinformatics, and comprises the following steps: firstly, obtaining a cryoelectron microscope experimental density map after redundancy elimination and a corresponding protein structure, generating a simulation density map, carrying out uniform sampling and density vector calculation, and converting into point cloud data; training and evaluating a registration network based on the point cloud data; secondly, predicting a single-chain structure of a to-be-assembled protein compound by utilizing AlphaFold3, processing in the same way according to the training data, firstly registering the longest chain, performing local optimization by using an LBFGS optimization algorithm, and if a correlation coefficient is lower than a threshold value and the chain comprises a plurality of structural domains, improving the precision by splitting the structural domains and performing independent registration; finally, the remaining chains are gradually fitted to the density map according to the chain length sequence. According to the method, point cloud registration and local optimization are combined, and the protein structure assembling precision and speed under the low-resolution density map condition are remarkably improved.

The invention provides an anti-PD-1 antibody, a CAR-T cell, and a preparation method and application thereof. The anti-PD-1 antibody comprises LCDR-1-3 as shown in SEQ ID NO: 1-3 and HCDR-1-3 as shown in SEQ ID NO: 4-6, respectively. The CAR-T cell expresses a novel element for efficiently blocking the PD-1, and the element is a single-chain antibody for targeting the PD-1 in a cell membrane anchoring manner. And the chimeric antigen receptor and the cell membrane anchored anti-PD-1 scFv are connected by a 2A cleavage protein. The membrane anchor type anti-PD-1 scFv expressed by the CAR-T cell can almost completely block the expression of PD-1 on the surface of a T cell membrane, and further block a signal channel combined with PD-1 / PD-L1, so that the capability of T cell depletion caused by antagonism tumor of the CAR-T cell is enhanced, and the purpose of enhancing the anti-tumor effect of the CAR-T cell is achieved.

The invention provides a single-chain and double-protein-expressed circular RNA construct and a preparation method and application thereof, and the single-chain and double-protein-expressed circular RNA construct comprises 5'and 3 'introns used for realizing RNA self-splicing and cyclization as a first kind of introns; the 5'and 3 'homologous arms are used as pairing sites in RNA molecules; the exon 1 and the exon 2, which are connected after being spliced, can be spliced and connected together under the action of the first type of introns to form a complete and continuous open reading frame; an interval sequence for providing spatial and adjustment sequence structures; the IRES is used for starting translation; a glycine-serine linker as a flexible linker; a green fluorescent protein for gene expression monitoring; a luciferase for producing light by a catalytic chemical reaction. All the advantages of the double-IRES system for generating natural complete protein are reserved, and the core defect of low efficiency can be thoroughly overcome.

The present invention is directed to a humanized BCMA single-chain variable fragment (scFv), comprising VH having the amino acid sequence of SEQ ID NO: 4 and VL having the amino acid sequence of SEQ ID NO: 5. The present invention is also directed to a BCMA chimeric antigen receptor fusion protein comprising from N-terminus to C-terminus: (i) a single-chain variable fragment (scFv) of the present invention, (ii) a transmembrane domain, (iii) at least one co-stimulatory domains, and (iv) an activating domain. This humanized BCMA-CAR-T cells have specific killing activity with secretion of cytokine IFN-gamma in CAR-T cells in vitro and in vivo.

The present invention provides novel antibodies and antigen binding fragments thereof that bind to human CD30. Also presented are single chain variable antibodies, chimeric antigen receptors and uses thereof. Methods of treating cancer are also disclosed.

The present application relates to siRNA and oligonucleotide agents for use in the prevention or treatment of SOD1-related neurodegenerative diseases or conditions, such as amyotrophic lateral sclerosis, ALS. The oligonucleotide agent comprises a double-stranded targeting oligonucleotide (siRNA) and a non-targeting single-stranded oligonucleotide (ACO), wherein the siRNA targets the mRNA region of the target gene SOD1.

The invention relates to screening methods. In particular, it relates to a method of identifying a functional TCR from a library of particles, which displays a plurality of different T cell receptors (TCRs). The method may comprise a) exposing the library of particles to a target antigen to identify TCRs that bind to the target antigen, b) transfecting a plurality of T cells with nucleic acid encoding TCRs identified in step (a), c) exposing the plurality of transfected cells to the target antigen, and d) selecting cells having TCR activity in the presence of the target antigen. Transfection of the T cells is such that each T cell comprises a nucleic acid encoding a single TCR from the library of particles, the nucleic acid is integrated into the genome of the T cell at a single identical pre-defined locus, and the TCR is in a single chain format and comprises an alpha chain variable domain, a beta cain variable domain and a constant domain. The T cells do not express endogenous TCR. A T-cell comprising a recombinase mediated landing pad, wherein the T cell constitutively expresses TCR constant domain and does not express endogenous TCR, is also claimed.

The invention discloses a single-chain antibody for recognizing an extracellular domain of a PPRV H protein and application of the single-chain antibody, and belongs to the technical field of genetic engineering. The amino acid sequence of a heavy chain variable region of the single-chain antibody is as shown in SEQ ID NO.5, and the amino acid sequence of a light chain variable region of the single-chain antibody is as shown in SEQ ID NO.9. The invention provides a single-chain antibody for recognizing a PPRV H protein extracellular region (185-609aa), a mouse is immunized through a PPRV H protein extracellular region protein, and VH and VL genes of the immunized monoclonal antibody are connected in series by using a monoclonal antibody preparation technology and a DNA molecular technology to prepare the single-chain antibody. A neutralization test verifies that the single-chain antibody can neutralize PPRV viruses and can be used for clinical detection of peste des petits ruminants.