23 results about "Protein s antigen" patented technology

The invention discloses a surface antigen gene StSAG1 of Sarcocystis tenella, the nucleotide sequence of the surface antigen gene StSAG1 is as shown in SEQ ID NO: 1, and according to the analysis result of protein antigenicity and antigen epitope, the 686 bp-1175 bp segment of the StSAG1 gene is selected to construct a recombinant protein expression vector and engineering bacteria; the antigen disclosed by the invention has very strong antigenicity and specificity, and can be subjected to effective antigen-antibody reaction with an antibody generated in serum after sheep (Ovis aries) is infected with sarcosporidium tenella, so that diagnosis is realized; low-titer antibodies can be detected two weeks after infection, and the detection window period is obviously advanced; by adopting the ELISA detection method, a visual result can be directly obtained. The method breaks through the limitation of an infection window period, has the advantages of low cost, high sensitivity, simplicity and convenience in operation, no need of expensive instruments and analysis and the like, is suitable for field detection in primary laboratories and pastures, and is beneficial to industrial production and market popularization and application.

The invention discloses a nano antibody targeting GPRC5D as well as a preparation method and application thereof, and belongs to the technical field of biological medicines. The nano antibody is generated by mixed immunization of a GPRC5D polypeptide antigen with a sequence shown as SEQ ID NO: 1 and a GPRC5D protein antigen with a sequence shown as SEQ ID NO: 2. The preparation method comprises the following steps: mixing the GPRC5D polypeptide antigen and the GPRC5D protein antigen to immunize alpaca, sampling blood, constructing an antibody library, screening a phage display antibody library, expressing protein, and selecting the nano antibody with the highest affinity. The invention further provides a radionuclide labeled molecular probe, the nano antibody is small in molecular weight and can recognize a large number of epitopes, and the molecular probe prepared from the nano antibody can obtain high-quality images, is used for preparing products for developing multiple myeloma or detecting GPRC5D expression level and has wide application prospects.

The application discloses a vaccine and a preparation method thereof, and the preparation method comprises the following steps: mixing an acidic protein antigen solution containing a phosphate buffer solution with an aluminum adjuvant to make the molar ratio of phosphorus and aluminum below 0.9, so as to obtain an acidic protein vaccine; or mixing the aluminum adjuvant with a solution containing phosphate ions to make the molar ratio of phosphorus and aluminum above 0.2, and then mixing the aluminum adjuvant with an alkaline protein antigen solution containing a phosphate buffer solution, so as to obtain an alkaline protein vaccine; wherein the acidic protein antigen is any kind of protein antigen with a net negative charge; and the alkaline protein antigen is any kind of protein antigen with a net positive charge. According to the preparation method, the molar ratio of phosphorus and aluminum is adjusted to a specific range according to the net charge of the protein antigen, so that the isoelectric point of the aluminum adjuvant can be effectively changed, the charge carried by the aluminum adjuvant is opposite to the charge carried by the protein antigen, and then the aluminum adjuvant and the protein antigen are attracted to each other through electrostatic interaction. The vaccine antigen prepared by the method has high antigen adsorption rate and good stability, the preparation method is simple, and the method is suitable for industrial application.

The invention provides a preparation method and application of a nitrogen-containing heterocyclic micromolecule modified polyethyleneimine polymer derivative. Compared with a polyethyleneimine polymer, the nitrogen heterocyclic ring micromolecule modified polyethyleneimine polymer derivative provided by the invention has immunostimulatory activity. Besides, the polymer derivative material provided by the invention can be simply mixed with a protein antigen to form nanoparticles, so that efficient loading of the protein antigen is realized, the delivery efficiency of the protein antigen to lymph nodes is improved, and the polymer derivative material can be used for preparing a novel nano vaccine preparation.

The invention relates to preparation, epitope identification and application of a PRV TK protein monoclonal antibody. The amino acid sequence of a light chain variable region of the monoclonal antibody is as shown in SEQ ID NO.2, and the amino acid sequence of a heavy chain variable region of the monoclonal antibody is as shown in SEQ ID NO.3. Meanwhile, the invention provides the PRV TK protein antigen epitope peptide, and the specific amino acid sequence of the PRV TK protein antigen epitope peptide is as shown in SEQ ID NO. 4. According to the research, on the basis that the PRV strain TK protein is successfully expressed, the PRV strain TK protein is purified to serve as an antigen to immunize a mouse, the specific monoclonal antibody aiming at the PRV strain TK protein is prepared by utilizing a hybridoma technology, and an important tool is provided for PRV epidemic strain TK protein structure and function research and subsequent establishment of a PRV specific diagnosis method and related research.

The invention provides a GP4 protein antigen epitope peptide of PRRSV (Porcine Reproductive and Respiratory Syndrome Virus) and a monoclonal antibody, and provides a hybridoma cell strain for generating the monoclonal antibody, and the preservation number of the hybridoma cell strain is CCTCC (China Center for Type Culture Collection) NO.C2025259. The monoclonal antibody provided by the invention does not react with various other swine viruses such as PCV2, PEDV, GETV and the like, and has good specificity; the polypeptide has good affinity with PRRSV structural protein GP4 at the molecular level and the cellular level, and epitope information is clear. The antibody can significantly inhibit the infection efficiency of a PRRSV-2 JXwn06 strain in MARC-145 cells and alveolar macrophages, has a good PRRSV in-vitro neutralization effect, can be used for developing a high-specificity PRRSV-2 GP4 detection reagent, and is expected to be used as a candidate drug for passive immune prevention and treatment of PRRS.

The present application belongs to the technical field of nanobody, and particularly relates to an anti-CHI3L1 nanobody, a construction method and application of a phage display library thereof. The present application discloses an anti-CHI3L1 nanobody, which is a nanobody aiming at an epitope of a CHI3L1 protein antigen, and has a VHH chain with an amino acid sequence shown as SEQ ID NO:1. The present application takes CHI3L1 as a research object, immunizes a llama after expression and purification of CHI3L1, and screens an anti-CHI3L1 nanobody by using phage display technology. The nanobody has the ability of high sensitivity and specificity in binding CHI3L1. The anti-CHI3L1 nanobody of the present application provides materials for establishing a diagnostic method and product of CHI3L1, and also provides a research direction for developing a drug for treating a disease related to CHI3L1.

The invention provides a complement protein C3C3b antigen epitope peptide as well as a related antibody and application thereof. The anti-complement protein C3 / C3b single structural domain antibody provided by the invention is combined with an MG6alpha-MG7-C345C structural domain and / or an MG6beta-MG6alpha-MG7-TED structural domain of the complement protein C3 / C3b, and can be competitively combined with a factor B to inhibit formation of C3 invertase, and the anti-complement protein C3 / C3b antibody or an antigen binding fragment thereof is small in molecular weight, high in affinity with the complement protein C3 / C3b and strong in complement inhibition activity, so that the anti-complement protein C3 / C3b single structural domain antibody or the antigen binding fragment thereof can be used for preparing the anti-complement protein C3 / C3b single structural domain antibody. Cracking of C3 and activation of a complement cascade reaction can be effectively blocked, and the compound can be potentially applied to treatment of diseases related to complement activation.

Provided are a complement protein C3C3b antigenic epitope peptide, and a related antibody thereof and the use thereof. The provided anti-complement protein C3 / C3b single-domain antibody binds to the MG6α-MG7-C345C domain and / or MG6β-MG6α-MG7-TED domain of complement protein C3 / C3b, and can compete with factor B for binding to C3b, thereby inhibiting the formation of a C3 convertase. Moreover, the anti-complement protein C3 / C3b antibody or an antigen-binding fragment thereof has a small molecular weight, exhibits a high affinity for complement protein C3 / C3b and a potent complement inhibitory activity, can effectively block the cleavage of C3 and the activation of complement cascade, and can be potentially used in the treatment of diseases associated with complement activation.

The application relates to preparation, epitope identification and application of a PRV TK protein monoclonal antibody, the amino acid sequence of the light chain variable region of the monoclonal antibody is shown as SEQ ID NO. 2, and the amino acid sequence of the amino acid sequence of the heavy chain variable region is shown as SEQ ID NO. 3. Meanwhile, the application provides a PRV TK protein antigen epitope peptide, and the specific amino acid sequence of the PRV TK protein antigen epitope peptide is shown as SEQ ID NO. 4. On the basis of successfully expressing a PRV strain TK protein, the PRV strain TK protein is purified and used as an antigen to immunize mice, and a hybridoma technology is used to prepare a specific monoclonal antibody for the PRV strain TK protein, so as to provide an important tool for TK protein structure and function research of a PRV epidemic strain, and subsequent establishment of a PRV specific diagnosis method and related research.

The invention relates to the technical field of biology, and particularly discloses a method for removing H3K27me3 in a plant by using a SunTag system. The method provided by the invention comprises the following steps: based on a SunTag system, the system comprises dcas9 protein-antigen protein GCN4 started by UBQ10; antibody protein scFv-sfGFP and guide RNA (Ribonucleic Acid). According to the system, through the guiding effect of gRNA, effect protein recruitment can be carried out on a specific site in an antigen-antibody binding mode. The editing method has a certain activation effect on genes which are modified by H3K27me3 and are expressed silently, a new thought and a new means are provided for plant gene function research and crop genetic improvement, deep understanding of a plant gene expression regulation mechanism is facilitated, and progress of plant breeding and agricultural production is promoted.

The present invention is inter alia directed to a combination comprising at least one nucleic acid molecule that encodes a combination of antigens that comprise an amino acid sequence encoded by ZC3H8-6:1, WDR72-2:4, KCNMB2-AS1:4, and NTF3-5:5. The combination of antigens optionally comprises at least one additional antigen that comprises an amino acid sequence from MAGEA3, MAGEA4, MAGEA11, and / or MAGEA9. The invention further relates to a composition comprising at least one nucleic acid molecule suitably formulated in lipid-based earners. The invention also provides a peptide or protein antigen combination, as well as a kit or kit of parts comprising the combination, the composition, and / or the peptide or protein antigen combination. Also provided herein is the combination, the composition, the peptide or protein antigen combination, or the kit or kit of parts, for use as a medicament, preferably for use in the treatment or prevention of a tumour or cancer disease, more preferably for use in the treatment or prevention of squamous cell carcinoma such as squamous non-small-cell lung cancer or head and neck squamous cell carcinoma.

The present disclosure belongs to the field of biological detection, and particularly relates to a protein antigen combination for detection of Alzheimer's disease (AD) and application thereof. The specific technical solution is as follows: An antigen combination is provided, wherein the antigen combination at least simultaneously includes the following proteins: DOC2A, LGALS1, KDM4D, and ADARB1. The present disclosure provides several new protein antigens and the combination thereof, which can be used for early-screening detection or diagnosis of AD, and are particularly suitable for risk assessment and prediction prior to the onset of AD. Meanwhile, the protein antigens and the combination thereof can distinguish AD from other types of dementia, and can be further prepared into related reagents or kits according to needs.

Disclosed herein are polypeptide constructs that engage a complement factor (such as C1q) and a target of interest. Various configurations of the polypeptide constructs and amino acid modifications for improved efficacy are discussed. The polypeptide constructs can be used in the treatment of a disease, for example, cancer, autoimmune diseases, obesity, neurodegenerative diseases, cardiovascular diseases, and metabolic diseases, among others.

The present invention belongs to the field of biological detection, and specifically relates to a protein antigen combination for aortic dissection detection and the use thereof. The specific technical solution comprises an antigen composition comprising an FBN2 protein fragment and an SPEG protein, wherein the FBN2 protein fragment has an amino acid sequence as shown in SEQ ID NO: 1, and the SPEG protein has an amino acid sequence as shown in SEQ ID NO: 5. Provided are a protein antigen and a specific combination of antigens, which, by means of detecting autoantibodies corresponding thereto, can be used for the detection or diagnosis of aortic dissection, are particularly suitable for risk assessment and prediction prior to the onset of aortic dissection, and can be further prepared into a related reagent or kit on the basis of requirements.

Provided are a virus peptide-protein subunit combination vaccine based on DNA nanotechnology, and a preparation method therefor and use thereof, which belong to the technical field of biological products. Provided is a virus peptide-protein subunit combination vaccine based on DNA nanotechnology, in which a tetrahedral framework nucleic acid formed by assembly of DNA strands is used as a vector, a protein antigen triggering virus-specific T cell activation is coupled to one edge of the tetrahedral framework nucleic acid, and B cell epitope peptides of a virus are coupled to four vertices of the tetrahedral framework nucleic acid.

Provided are a protein antigen combination for acute myocardial infarction detection, and the use thereof. The antigen combination at least comprises a cTnI (31-164) protein fragment having an amino acid sequence as shown in SEQ ID NO: 1. The antigen combination can be used in an antigen composition for detecting acute myocardial infarction, and can be further prepared into a related reagent or kit on the basis of need.

The application provides a novel HPV fusion protein antigen, a preparation method and application in preparation of polyclonal yolk antibody, which first connects core antigen peptides of human papilloma virus 16 subtype and HPV 18 subtype capsid protein L1 with Fc of immunoglobulin IgY and tail peptides of immunoglobulin IgM in series, and the above-mentioned recombinant fusion protein antigen is prepared by means of E. coli expression and inclusion body renaturation technology, which is beneficial to improving antigen peptide stability and presentation capacity, and the novel HPV fusion protein antigen is directly used for immunizing laying hens, after antibody production, the antibody is purified through steps such as salting-out and dialysis, and verification shows that the obtained yolk antibody can combine with L1 proteins of HPV16 and HPV18, and has the ability of preventing or treating HPV16 and HPV18 infection.

The disclosure relates to HSV glycoprotein E antigenic peptide constructs and HSV protein vaccines, as well as methods of using the vaccines and compositions comprising the vaccines. The present invention directed to immunogenic polypeptides of use for a vaccine against Herpes Simplex Virus (HSV). The polypeptides are glycoprotein E peptides that are mutated to reduce their binding to antibody Fc domain.

The invention provides an SARS-CoV-2 spike protein antigen epitope mixed polypeptide and application thereof, particularly relates to an SARS-CoV-2 related mixed polypeptide, a nucleic acid for encoding the mixed polypeptide, a carrier containing the nucleic acid, a cell containing the nucleic acid or the carrier, and also provides a vaccine. The mixed polypeptide provided by the invention comprises epitopes aiming at CD4 + T cells, CD8 + T cells and B cells, which are obtained by screening through various bioinformatics tools, can induce strong body fluid, cell and mucous membrane immune responses, and provides cross protection for a plurality of SARS-CoV-2 variants. Through reasonable design and matching of a specific type of polypeptide combination for intranasal delivery, broad-spectrum immune response can be induced, and a powerful basis is provided for future development of mucous membrane polypeptide vaccines of other respiratory viruses.

Disclosed is a method for improving the immunogenicity of a protein / peptide antigen, the method comprising conjugating a protein / peptide antigen with a sugar to form a sugar-protein / peptide antigen conjugate, which has improved immunogenicity compared to an unconjugated protein / peptide antigen. In particular, the method involves conjugating a pathogen, such as a viral surface protein antigen or a fragment thereof, with a polysaccharide, in particular a capsular polysaccharide of Streptococcus pneumonia. The conjugate with improved immunogenicity can be used to prevent or treat diseases caused by pathogens, in particular diseases caused by coronaviruses.

The present application relates to the field of immunological examination, in particular to a kind of capture microbead and preparation method and its use, the present application provides a kind of preparation method of capture microbead, comprising: (1), aldehyde / sulfate latex microspheres stock solution is diluted using zwitterionic buffer, then first centrifugation is discarded supernatant, and then resuspended and washed with zwitterionic buffer, then second centrifugation is discarded supernatant, and then resuspended with zwitterionic buffer, obtain aldehyde / sulfate latex microspheres resuspension;(2), restore protein antigen is added to aldehyde / sulfate latex microspheres resuspension, incubation, then centrifugation is discarded supernatant, obtain the aldehyde / sulfate latex microspheres coated with restore protein antigen, then blocking, washing, preservation is carried out;The capture microbead obtained by the above preparation method has high specificity, accuracy and precision when detecting anti-retinal antibody.

The application discloses a method based on solid-phase glycoprotein T antigen glycopeptide enrichment and enzyme cutting analysis, which comprises the following steps: extracting protein from a sample; obtaining polypeptide through proteolysis; oxidizing galactose and N-acetyl galactose; fixing with hydrazide resin and cutting with PNGase F enzyme; treating with galactoside enzyme and performing mass spectrometry analysis. The method obtains three structures, T antigen glycopeptide of core 1, core 2 glycopeptide and core 8 glycopeptide. The T antigen glycopeptide and the core 2 glycopeptide are distinguished through mass spectrometry analysis, and the T antigen glycopeptide and the core 8 are distinguished through different glycosidases. The method can enrich and distinguish glycopeptides containing T antigens, core 2 and core 8, and has important significance for finding specific markers with T antigen modification in tumor tissues and body fluids, research on early diagnosis and prognosis markers of diseases and the like.