451 results about "Single-Chain Antibodies" patented technology

Provided herein are methods, compositions, and kits including single-chain antibody nucleic acid libraries and methods of displaying single-chain antibodies and screening single-chain antibodies on a spatial array.

The present disclosure provides bispecific chimeric antigen receptors targeting CD20 and BCMA. The CAR may comprise an scFv targeting CD20 and an scFv targeting BCMA, a hinge region, a transmembrane domain, a co-stimulatory region, and a cytoplasmic signaling domain. The chimeric antigen receptors can be used to treat autoimmune disorders or cancer.

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 discloses an artificial antigen presenting cell for efficiently preparing a chimeric antigen receptor T cell (CAR-T) and a construction method of the artificial antigen presenting cell, and belongs to the field of cell therapy and immunotherapy, the artificial antigen presenting cell takes a K562 cell as a platform, an anti-CD3 single-chain antibody, an anti-CD28 single-chain antibody, a membrane binding type cell factor and a costimulatory ligand are stably expressed through genetic engineering, and the chimeric antigen receptor T cell (CAR-T) is obtained. And the local concentration of the anti-CD3 antibody is improved by adopting an HOTag3 tool. The multi-signal integration strategy obviously enhances the activation and proliferation capacity of the T cells, promotes the CAR-T cells to maintain a low differentiation state, and endows the CAR-T cells with excellent anti-tumor activity and durability. The artificial antigen presenting cell provides a novel efficient tool for the field of cellular immunotherapy, and is expected to promote development of more efficient and safer CAR-T therapy to cope with challenges of various malignant tumors.

The invention provides a CAR-NK cell for knocking out KIR2DL5 targeting HER2 as well as a preparation method and application of the CAR-NK cell, and belongs to the technical field of genetic engineering.The CAR-NK cell is obtained by adopting a chimeric antigen receptor with HER2 as a target spot to infect an NK cell and then knocking out a KIR2DL5 gene; the chimeric antigen receptor taking the HER2 as the target spot comprises an HER2 single-chain antibody; the nucleic acid artificial sequence of the HER2 single-chain antibody is as shown in SEQ ID NO. 2. According to the application disclosed by the invention, the interaction of KIR2DL5-PVR is blocked by knocking out NK cell immune checkpoints, so that tumor immune escape is avoided, and the activity of killing tumor cells by CAR-NK cells is remarkably enhanced; according to the invention, by optimizing the nucleic acid artificial sequence of HER2, the secretion ability of CAR-NK cell factors, the tumor killing efficiency and the in-vivo inhibition effect on tumors can be improved.

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.

The invention provides nano-particles for generating CAR-T in vivo and application of the nano-particles, and belongs to the technical field of medical preparations. The nanoparticles are nanoparticles which are coupled with a CD7 antibody and entrapped with mRNA (messenger Ribonucleic Acid); the mRNA is obtained by transcription of a target gene; the target gene comprises a TROP2 single-chain antibody; the nucleotide sequence of the TROP2 single-chain antibody is as shown in SEQ ID NO: 1. The nucleotide sequence of the TROP2 single-chain antibody is optimized, the CAR containing the TROP2 single-chain antibody is constructed, then the CAR is transcribed to obtain mRNA, LNP entrapped with mRNA is prepared, then the CD7 antibody subjected to amino acid sequence optimization is adopted to be coupled with the LNP entrapped with mRNA, the transfection efficiency of the CD7 antibody in T cells is high, the CD7 antibody is injected into a mouse tumor model, and the lifetime of mice can be prolonged; t cells transfected by the T cell transfecting agent have high killing efficiency on HELA cells and LOVO cells.

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 CD8 antibody modified anti-TIM-3 lipid nanoparticle as well as a preparation method and application thereof, and belongs to the technical field of medical preparations. The lipid nanoparticle contains a chimeric antigen receptor; the chimeric antigen receptor comprises a single-chain antibody TIM-3; the nucleic acid artificial sequence of the single-chain antibody TIM-3 is as shown in SEQ ID NO. 5. According to the application, sequence optimization is carried out on a TIM-3 target spot, a CAR structure connected with a double-stimulating factor and a suicide gene is prepared, and anti-TIM-3 nano-lipid particles modified by a CD8 antibody are constructed and delivered into cells, so that CD8 + T cells can be effectively captured in a body, CAR-T cells can be generated, a complex process of in-vitro preparation is omitted, and the application has the advantages of simplicity, convenience in operation and high efficiency. The activation degree of T cells is improved while the antigen is efficiently recognized, the efficient anti-tumor effect is achieved, the survival time of breast cancer mice is obviously prolonged, and the growth of tumors is inhibited.

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 relates to an application of a macrophage expressing an anti-uPAR chimeric antigen receptor in preparation of an anti-aging drug, and discloses a new application of the macrophage (CAR-M) expressing the anti-uPAR chimeric antigen receptor in senescence diseases, and the mechanism is that uPAR positive cells are specifically recognized and apoptosis of the uPAR positive cells is induced by targeting senescence cell surface antigen uPAR. According to the uPAR-CAR-M, a humanized anti-uPAR single-chain antibody is used as a chimeric antigen receptor recognition region, so that the chimeric antigen receptor has high specificity, and the chimeric antigen receptor is used for promoting the functions of macrophages by using a CD8 alpha transmembrane structural domain, a CD28 costimulatory molecule and a Megf10 sequence, so that a better killing effect is given to the CAR-M. The problems of inflammatory microenvironment caused by abnormal aggregation of senescence cells, chronic tissue damage and senescence-related disease treatment disorder are solved, and the application value for treating senescence-related diseases (such as osteoarthritis and the like) expressing uPAR is important.

Provided are a CAR library used to screen scFvs that can be functional in CAR-T cells, and an scFv manufacturing method in which the CAR library is used. A chimeric antigen receptor (CAR) library of the present invention includes nucleic acids coding for first CARs. Each of the first CARs includes a first antigen-binding domain, a first transmembrane domain, and a first intracellular signaling domain. The first antigen-binding domain includes a first single-chain antibody (scFv) to be screened for the ability to bind to a target antigen. The first scFv includes a first heavy-chain variable region and a first light-chain variable region. The first heavy-chain variable region and the first light-chain variable region meet a predetermined condition.

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 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.

Disclosed herein are multi-valent, multi-specific, single-chain antibodies with specificities for four antigens selected from EGFR, PD-L1, HSA, CD28, CD3E, OX-40, CD40, 4-1BB, LAG3, and CD16A.

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 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.

The invention relates to the technical field of biological medicine, in particular to a medicine for improving thyroid-related eye diseases and application of the medicine. The single-chain antibody provided by the invention has small molecular weight and good physiological activity, and can effectively inhibit the activity and function of IGF1R mediated by IGF1, thereby inhibiting cell proliferation. According to the medicine prepared from the recombinant adeno-associated virus, the treatment cost can be remarkably reduced, side effects caused by repeated injection of antibody medicines are avoided, the safety is very high, and a new clinical treatment method and strategy are provided for inhibiting pathological phenotypes of thyroid-associated ophthalmopathy.