305 results about "Antigenicity" patented technology

The invention belongs to the technical field of biology, and discloses a stable protective agent, a cell antigen dry sheet and a preparation method and application of the dry sheet, the stable protective agent comprises glycerin with the volume fraction being 0.4%, gelatin with the mass volume fraction being 0.1%, EDTA with the mass volume fraction being 0.1 mM, trehalose with the mass volume fraction being 0.03% and resveratrol with the mass volume fraction being 100 [mu] M. The stable protective agent is adopted for preparing the cell antigen dry sheet, and the cell antigen dry sheet is applied to CBA detection. The stable protective agent has good permeability, can penetrate through cell membranes to enter cells, provides a protection effect inside and outside the cells, has moisture retention and oxidation resistance, can prevent cell deformation and cell fixing layer shedding, and can well maintain the stability and reliability of antigen proteins, and the prepared cell antigen dry sheet can be stored for a long time, and has a good application prospect. The antigenicity of a membrane signal index is not damaged. When a positive sample is detected, obvious green fluorescence cells can be seen, red fluorescence quenching is avoided, and co-localization of red fluorescence and green fluorescence can be observed conveniently.

The invention provides a specific monoclonal antibody for detecting rotavirus and application of the specific monoclonal antibody, aiming at an epidemic strain of porcine rotavirus, reference to a gene sequence of VP6 protein published by GenBank, antigen epitopes are further optimized, and purified recombinant VP6 protein with antigenicity is obtained for animal immunization. The monoclonal antibody capable of specifically recognizing the porcine rotavirus is successfully screened out. The monoclonal antibody obtained through screening can effectively recognize epidemic strains, has broad-spectrum recognition, is superior to commercially available antibodies, and has high antigen recognition target performance and low non-specificity. And the sequence background is clear, large-scale amplification and production can be carried out, and the method has good commercial value.

The invention provides a respiratory syncytial virus antigenic polypeptide, nucleic acid and a vaccine. Compared with the respiratory syncytial virus wild type Pre-F protein, the respiratory syncytial virus antigenic polypeptide or the immunogenic fragment of the respiratory syncytial virus antigenic polypeptide has the following changes: the 104th to 144th regions of the Pre-F protein are replaced with GS linker; two groups of disulfide bonds are introduced into S155C, S290C, A149C and Y458C; the S190F and the V207L are used for realizing cavity filling; and P102A, L373R, I379V, M447V, P102A, L373R, the C terminal of the respiratory syncytial virus antigenic polypeptide or the immunogenic fragment thereof comprises a cytoplasm tail region fragment, and the cytoplasm tail region fragment is a fragment derived from 3-10 continuous amino acid residues of a PreF protein cytoplasm tail region. According to the present invention, the pre-F immunogenicity and / or stability can be improved, and the protein expression level can be easily improved.

This disclosure relates to fusion proteins comprising one or more EBV polypeptides and a ferritin protein, and their use in eliciting antibodies against EBV.

The invention provides an antigen epitope peptide related to connexin and application of the antigen epitope peptide. The connexin antigen epitope peptide disclosed by the invention is selected from (1) a polypeptide with an amino acid sequence as shown in SEQ ID NO: 14; and (2) a polypeptide which is derived from (1) by substituting, deleting or adding 1-2 amino acids in the amino acid sequence of SEQ ID NO: 14 and retains the binding capacity with a connexin antibody. According to the present invention, the new connexin antigenic peptide fragment sequence is identified for the first time, such that the existing autoantigen epitope map is expanded, and more importantly, the molecular basis is provided for the development of the clinical detection method with high diagnosis sensitivity and high specificity, such that the pathological mechanism of MG can be further improved, and the application prospect is broad. And new auxiliary diagnosis means and treatment targets are provided for antibody negative MG patients.

The present disclosure provides lipid nanoparticle compositions comprising a nucleic acid encoding an RSV antigenic polypeptide. The invention also provides novel antigenic RSV-F polypeptides as well as nucleic acids encoding the antigenic RSV-F polypeptides.

The invention relates to a vaccine for preventing and treating sheep echinococcosis infection and a preparation method thereof.The preparation method comprises the steps that echinococcosis Eg95 full-length gene antigen epitopes are screened through bioinformatics software, screened fragments with high antigenicity are optimized and then subjected to double-copy connection through a flexible linker, His tag sequences are added to the two ends of a tandem sequence, the sequence is as shown in SEQ ID NO.2, and the vaccine for preventing and treating sheep echinococcosis infection is obtained; and the pEE12.4-double Eg95 plasmid is connected with a CHO eukaryotic cell expression vector, so that the pEE12.4-double Eg95 plasmid is obtained. The plasmid is integrated into a CHO eukaryotic cell expression system, the expression quantity of the purified Eg95 protein reaches 10g / L, and a stable and high-yield veterinary vaccine is provided for large-scale production.

The invention discloses an H9N2 subtype avian influenza virus, the H9N2 subtype avian influenza virus is A / chick / Guangxi / C1228 / 2015 (H9N2), and the preservation number of the H9N2 subtype avian influenza virus is CGMCC (China General Microbiological Culture Collection Center) No.45222; or the H9N2 subtype avian influenza virus is A / quil / Guangxi / 210Q33 / 2015 (H9N2), and the preservation number is CGMCC (China General Microbiological Culture Collection Center) No. 46091. The bivalent inactivated vaccine of CK / GX / C1228 / 15 with better antigenicity and the strain QL / GX / 210Q33 / 15 which has better antigenicity and is separated from quails in the live poultry market has a better protection effect on two different branches of H9N2 subtype avian influenza viruses, the lowest immune dose (0.3 mL) can reach the protection rate of 80% or above, and the generated effective protection antibody can last to 24W.

The invention discloses lactobacillus paracasei capable of reducing casein antigenicity and application of the lactobacillus paracasei capable of reducing casein antigenicity, the strain is Lacticasei paracasei DPU-MWFLp-47 and preserved in the China General Microbiological Culture Collection Center, the preservation number is CCTCC M 20232093, the preservation number is CCTCC M 20232093, and the lactobacillus paracasei capable of reducing casein antigenicity and application of the lactobacillus paracasei capable of reducing casein antigenicity are applied to lactobacillus paracasei DPU-MWFLp-47. The strain can effectively reduce the antigenicity and potential sensitization of alpha-casein by cutting IgE binding epitopes.

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 fixing reagent and method for double-color fluorescence detection of an anti-NMDAR antibody and application, the fixing reagent comprises paraformaldehyde and a mixture of methanol and acetone, and the mixture comprises 10-25% by volume of methanol, 75-90% by volume of acetone, 10-25% by volume of paraformaldehyde, 10-25% by volume of paraformaldehyde and 10-25% by volume of paraformaldehyde. The fixing effect is better by adopting paraformaldehyde with the mass-volume ratio concentration of 4% and a mixture of methanol with the volume fraction of 15% and acetone with the volume fraction of 85% in two steps. By adopting the fixing liquid and the fixing method, the antigenicity of NMDAR cannot be damaged, obvious green fluorescence cells can be seen in a positive sample, red fluorescence quenching is avoided, and co-localization of red fluorescence and green fluorescence can be observed by using a fluorescence microscope.

The invention belongs to the technical field of cell engineering and biochemical detection, and particularly relates to an erythrocyte membrane with a complete structure and a preparation method and application thereof. The red blood cells are split by limiting the components of the release liquid, the conditions are mild, protein components such as hemoglobin in the red blood cells can be released, the cell attributes are removed, the integrity of the internal skeleton structure and the activity of the membrane surface antigen are reserved, the complete structure of the red cell membrane is kept, meanwhile, the key blood group antigen on the surface is reserved, and the effect is good. The problem of antigenicity reduction caused by erythrocyte membrane fragmentation is avoided. After the erythrocytes are lysed, the nanoparticles are coupled to the surface of the erythrocyte membrane, so that the agglutination reaction of the erythrocyte membrane under the induction of the antibody can be visualized. The engineering red blood cell biological membrane is preserved by adopting a fixed program, so that the damage of ice crystals to the engineering red blood cell biological membrane can be effectively avoided, the antigenicity of the membrane is not influenced, the membrane can be preserved for a long time at normal temperature, and the shelf life can be prolonged to two years or more.

The invention is applicable to the technical field of biology, and provides an L7 / L12-PADRE sequence-multi-linked B cell epitope recombinant protein and a kit for detecting an anti-Brucella antibody. The recombinant protein is a multi-epitope tandem recombinant protein composed of Brucella ribosome L7 / L12 protein, a PADRE polypeptide sequence and multiple B cell epitopes, the amino acid sequence of the recombinant protein is as shown in SEQ ID No.1, and the recombinant protein is good in antigenicity. The anti-brucella antibody indirect ELISA (iELISA) detection method and kit established by taking the recombinant protein as the coating antigen have the characteristics of high sensitivity, strong specificity and good repeatability, are suitable for detecting the condition of generating the anti-brucella antibody by an organism, can clarify the immune background of brucella infection or brucellosis vaccine, and can be used for detecting the brucella infection or brucellosis vaccine. Basic data is provided for prevention and control of the Brucella disease of humans and animals, and meanwhile, the kit is conveniently applied to large-scale sample detection and epidemiological monitoring.

The growth factor profile, connective tissue matrix constituents, and immunoprivileged status of urodele extracellular matrix (ECM) and accompanying cutaneous tissue, plus the presence of antimicrobial peptides there, render urodele-derived tissue an ideal source for biological scaffolds for xenotransplantation. In particular, a biological scaffold biomaterial can be obtained by a process that entails (A) obtaining a tissue sample from a urodele, where the tissue comprises ECM, inclusive of the basement membrane, and (B) subjecting the tissue sample to a decellularization process that maintains the structural and functional integrity of the extracellular matrix, by virtue of retaining its fibrous and on-fibrous proteins, glycoaminoglycans (GAGs) and proteoglycans, while removing sufficient cellular components of the sample to reduce or eliminate antigenicity and immunogenicity for xenograft purposes. The resultant urodele-derived biomaterial can be used to enhance restoration of skin homeostasis, to reduce the severity, durations and associated damage caused by post-surgical inflammation, and to promote progression of natural healing and regeneration processes. In addition, the biomaterial promotes the formation of remodeled tissue that is comparable in quality, function, and compliance to undamaged human tissue.

The invention discloses a method for removing antigen protein from soybean meal, which comprises the following steps: putting a soybean meal raw material into a digester, and carrying out two-stage temperature-controlled cooking: in an initial heating stage, raising the temperature in the digester from normal temperature to 80 DEG C at a heating rate of 5-10 DEG C / min for about 10-15 minutes; and a high-temperature cooking stage: continuously raising the temperature to 110-121 DEG C, and keeping the temperature for 20-30 minutes. In the high-temperature cooking process, the temperature fluctuation range should be controlled within + / -1 DEG C, and the pressure in the cooking pot is maintained at 0.1-0.15 MPa. According to the method for removing the antigen protein from the soybean meal provided by the invention, the structure of the antigen protein is denatured and inactivated by controlling conditions such as specific temperature, time, pressure and the like, so that the antigenicity of the antigen protein is reduced, and subsequent production or application requirements are met.

The present invention relates to a recombinant chimeric antigen targeting poxvirus (particularly monkeypox virus), a subunit vaccine thereof, and its application. The recombinant chimeric antigen of the present invention comprises two immunogens arranged in a specific manner: monkeypox virus A35 protein or its antigenic fragment (or its derivative peptide segment) and monkeypox virus M1 protein or its antigenic fragment (or its derivative peptide segment), which can stimulate immune responses against two infectious virus particles: intracellular mature virus particles (IMV) and extracellular enveloped virus particles (EEV), thereby efficiently stimulating specific immune protection against monkeypox virus. In addition, the poxvirus vaccine of the present invention also has good safety, rapid responsiveness and production capacity support, and has excellent clinical application prospects.

The invention relates to a colloidal gold test strip for detecting a sheep pox virus antibody as well as a preparation method and application of the colloidal gold test strip. According to the invention, firstly, a recombinant 122 protein is prepared, and the recombinant 122 protein has remarkable antigenicity and immunogenicity and can be used as a good target for diagnosing the sheep pox virus; secondly, the colloidal gold test strip for detecting the sheep pox virus antibody is prepared, a sample pad, a gold-labeled pad, a nitrocellulose membrane and a water absorption pad are sequentially arranged on a PVC base plate of the test strip, and the gold-labeled pad is coated with gold-labeled recombinant 122 protein; the test strip can simultaneously detect antibodies of the sheep pox virus, the bovine nodular skin disease virus and the goat pox virus, the sensitivity can reach 1: 128, 1: 128 and 1: 64 respectively, the test strip has no cross reaction with bovine viral diarrhea virus, foot-and-mouth disease O-type virus, foot-and-mouth disease A-type virus, orf virus, brucellosis and colibacillosis, the specificity is good, and the diagnosis coincidence rate reaches 93%.

The invention discloses a multi-epitope peptide of novel coronavirus, a vaccine as well as a preparation method and application of the multi-epitope peptide, and belongs to the technical field of preparation of polypeptide vaccines. The multi-epitope peptide of the novel coronavirus not only contains T cell epitopes, but also contains B cell epitopes, and can induce humoral immunity and cellular immunity responses of an organism at the same time; the vaccine comprises epitopes from four antigenic proteins of novel coronavirus, and can induce comprehensive immune response. According to the multi-epitope peptide vaccine based on the novel coronavirus, the nano-carrier KFE8 serves as a delivery carrier, different antigen epitopes of the same pathogen or antigen epitopes of different pathogens can be presented in a mixed mode, safety is good, large-scale rapid preparation is achieved in an emergency state, and the vaccine is suitable for large-scale popularization and application. The coronavirus vaccine is a novel coronavirus universal vaccine which can cover various pathogen subtypes and induce broad-spectrum and long-term immune effects.

The invention provides a respiratory syncytial virus antigenic polypeptide, nucleic acid, a vaccine and application thereof. The invention firstly provides a respiratory syncytial virus antigenic polypeptide or an immunogenic fragment thereof, and the respiratory syncytial virus antigenic polypeptide has at least 26th-470th or full-length amino acid sequence as shown in SEQ ID NO: 1, or a derivative amino acid sequence which is formed by replacing, deleting or adding one or more amino acids on the basis of the amino acid sequences and has the same function. According to the invention, the pre-F immunogenicity can be improved and / or the protein expression level can be improved.

The invention discloses an enzyme-labeled secondary antibody polymer for immunohistochemical staining. The enzyme-labeled secondary antibody polymer is formed by combining a secondary antibody and a polymer skeleton, the polymer is labeled by a labeling enzyme, the polymer skeleton is polymethylacrylic acid-2-hydroxyethyl ester, and the labeling enzyme is connected to the polymethylacrylic acid-2-hydroxyethyl ester through a coupling agent. According to the invention, polymethylacrylic acid-2-hydroxyethyl ester is used for modifying protein, so that the immunogenicity and antigenicity are reduced, the hydrolysis of protease can be weakened, and the solubility of protein molecules is improved. The enzyme-labeled secondary antibody polymer is applied to immunohistochemical staining and has high specificity and sensitivity.

The invention provides a recombinant III-type collagen, nucleic acid, an expression vector, a bacterial strain and application of the recombinant III-type collagen. The recombinant collagen has the advantages of high expression quantity, low toxicity, low antigenicity, low immunity and the like, can guide cell regeneration, and is relatively good in biocompatibility. And when being applied in a human body, the antibody is low in generated immune response and has a wide application prospect. The preparation method is simple, green and environment-friendly, and is suitable for the industries of biological medicine, cosmetics, skin care products, food and the like.

The invention belongs to the field of gene engineering, and provides a mycoplasma ovipneumoniae multi-epitope fusion protein and preparation and application thereof.The inventor firstly successfully predicts antigen epitopes of three virulence genes and performs tandem expression on the predicated antigen epitopes to prepare a fusion protein antigen, and the fusion protein antigen is used for preparing the mycoplasma ovipneumoniae multi-epitope fusion protein. A secondary structure, a tertiary structure, physicochemical properties (including hydrophilicity, stability, PI value and the like), antigenicity, sensitization and the like of the fusion protein are predicted through biological online software, and the success rate of a test is increased; meanwhile, the fusion protein connected in series with the three virulence genes of the mycoplasma ovipneumoniae is prepared into a subunit vaccine, and a good immune protection effect is also achieved. The recombinant mycoplasma ovipneumoniae multi-epitope fusion protein prokaryotic expression plasmid pET28a < + >-EHP is successfully constructed, tandem expression of mycoplasma ovipneumoniae on an escherichia coli prokaryotic system is achieved, and an expression product can obtain a good immune protection effect.

The invention discloses a method for establishing duck hepatitis virus antibody ELISA (enzyme-linked immuno sorbent assay) detection, which comprises the following steps: firstly, preparing experimental materials, and then cloning and antigenicity analysis of structural genes, inducible expression of positive recombinants in escherichia coli, expression and purification of recombinant proteins, antigenicity analysis of the recombinant proteins and establishment of a recombinant antigen VP3 indirect ELISA method. Finally, VP0, VP3 and VP1 recombinant proteins can react with duck anti-DHV-1 positive serum and have good antigenicity, indirect ELISA results show that under the same coating concentration, the P / N value of the fusion protein GST-VP3 serving as a coating antigen is higher than that of the fusion protein GST-VP3 serving as the coating antigen and that of the fusion protein GST-VP3 serving as the coating antigen, it is indicated that the antigenicity of the fusion protein GST-VP3 is better than that of the fusion protein GST-VP3 serving as the coating antigen and that of the fusion protein GST-VP3 serving as the coating antigen and that of the fusion protein GST-VP3 serving as the coating antigen and that of the fusion protein GST-VP3 serving as the coating antigen and that of the fusion protein and the result is consistent with the prediction result.

The invention relates to a multi-antigen monkey pox RNA vaccine and a preparation method thereof, and relates to the technical field of nucleic acid vaccines. The multi-antigen mRNA comprises a sequence encoding an antigenic polypeptide of the monkey pox virus or an antigenic fragment, variant or derivative thereof, the antigenic polypeptide or the antigenic fragment thereof comprising at least viral proteins of an intracellular mature virus and an extracellular envelope virus of the monkey pox virus. The invention provides a multi-antigen mRNA vaccine aiming at monkey pox viruses and a sequence, mRNA can express antigen protein in in-vitro cells, high-titer anti-monkey pox virus A29L, A33L, B6R, M1R and E8L protein IgG can be detected after a mouse is immunized, a high-titer anti-vaccinia Tian Tan strain live virus neutralizing antibody is generated, good immunogenicity is achieved, and the vaccine can be used for preparing the multi-antigen mRNA vaccine aiming at the monkey pox viruses. The important significance is realized on the prevention of the monkey pox virus.

The invention discloses a carrier protein with an adjuvant function and application thereof. The carrier protein with the adjuvant function has a sequence as shown in SEQ ID NO. 1. According to the carrier protein with the adjuvant function, a part of sequence is intercepted from the flagellin FliC of Burkholderia cepacia, so that the adjuvant activity of the flagellin is reserved, and the immunogenicity and antigenicity of the flagellin are reduced; when being applied to a fusion protein or a small-molecule drug, the fusion protein or the small-molecule drug can enhance the immunogenicity, so that the fusion protein or the small-molecule drug has important significance on subunit vaccines, polypeptide vaccines or small-molecule drug carriers.

The invention relates to a recombinant chimeric antigen aiming at bovine nodular skin disease virus, an immunogenic composition containing the recombinant chimeric antigen and application of the recombinant chimeric antigen. The bovine nodular skin disease virus recombinant chimeric antigen comprises two immunogens which are connected in series and fused according to a specific sequence: bovine nodular skin disease virus ORF122 and ORF060 proteins or antigenic fragments thereof, and can excite immune response aiming at two infectious virus particles, namely, intracellular mature virus particles (IMV) and cell outer enveloped virus particles (EEV); therefore, the specific immune protection effect on the bovine nodular skin disease virus is efficiently excited; in addition, the bovine nodular skin disease virus vaccine disclosed by the invention also has good safety, quick responsiveness and productivity support, and has an extremely good clinical application prospect.

The invention provides a double-layer collagen scaffold repair membrane as well as a preparation method and application thereof, and the preparation method comprises the following steps: extracting collagen from animal fur, and emulsifying to obtain a collagen emulsion; adding a cross-linking agent into the collagen emulsion, and emulsifying to obtain a cross-linked protein emulsion; pouring the cross-linked protein emulsion into a mold, and freeze-drying to obtain a cross-linked protein layer; and pouring the collagen emulsion on the cross-linked protein layer, and freeze-drying to obtain the double-layer collagen scaffold repair membrane. The repairing membrane is excellent in structure, the cross-linked protein layer provides mechanical strength and supporting performance, the collagen layer can be rapidly dissolved and attached to the contact surface, and oxygen exchange and metabolite discharge of the wound surface are facilitated; the collagen is high in purity, low in antigenicity and high in safety, any toxic and harmful chemical reagents and preservatives are not added, allergy or inflammatory reaction is avoided, and the collagen has good application prospects in the fields of medical treatment, medical beauty, beauty, skin care and the like.

The invention, in some aspects, relates to compositions comprising modified viral nucleocapsid (N) proteins and their encoding polynucleotides and methods of using such compositions and preparations to increase viral N protein dimerization and / or increase antigenicity of viral immunization preparations.

The invention provides a medical absorbable collagen antibacterial suture line and a preparation method thereof. The preparation method comprises the following steps: S1, sequentially carrying out pretreatment, homogenization, digestion, sterilization, salting-out and purification on animal skin to obtain collagen; s2, performing solution blending on collagen and a chitosan derivative to prepare a spinning solution; s3, performing wet spinning on the spinning solution to obtain a wire rod; and S4, crosslinking or weaving the wire rod to prepare the medical antibacterial suture line capable of absorbing collagen. The suture line is high in collagen purity, in a special fiber bundle shape, low in antigenicity, good in spinnability, smooth in surface, soft and smooth in line body and easy to knot, does not need to be soaked before being used, can reduce scar hyperplasia and avoid centipede-shaped suture traces during suture, has antibacterial and hemostatic functions, and is suitable for clinical application. A physical hemostasis barrier can be quickly generated in the suturing process, and an excellent suturing effect is achieved.

This disclosure relates to antigenic respiratory syncytial virus (RSV) polypeptides for use in eliciting antibodies against RSV. Also disclosed are antigenic polypeptides comprising an RSV polypeptide and a ferritin protein.