41 results about "Epidemic strain" patented technology

The invention belongs to the field of biology, and discloses an mRNA (messenger ribonucleic acid) with a nucleotide sequence as shown in SEQ ID NO.3. Antiserum of a strain (A / chick / Gansuu / 28 / 2024) corresponding to the mRNA has relatively good reactivity with other strains and poorer reaction with a current vaccine strain RE-13, the branched strain is a current epidemic strain, and the mRNA prepared from the HA gene of the strain has the advantage of strong protection; the invention also aims to provide the mRNA, application thereof and a vaccine.

The application discloses a novel trimeric recombinant protein vaccine. Specifically disclosed are a mutant protein RBD8M with an amino acid sequence of SEQ ID No. 1 and a fusion protein of positions 26-277, positions 1-277 and SEQ ID No. 4. The application also discloses a vaccine containing the fusion protein, and further develops a trimeric recombinant protein vaccine containing the fusion protein and a double adjuvant. Experiments show that the vaccine prepared in the application can effectively induce cellular immunity and humoral immunity of the body in animals, a trace amount of the protein can stimulate a very high immune response of mice, has a good protection effect, can simultaneously produce high-titer neutralizing antibodies against various epidemic strains of the novel coronavirus, is a broad-spectrum effective new coronavirus vaccine, and has important significance for preventing novel coronavirus infection and a wide clinical application prospect.

The invention discloses a porcine epidemic diarrhea and porcine rotavirus (G9 type) bigeminy attenuated vaccine and a preparation method thereof, and relates to the technical field of veterinary biological products. According to the present invention, dominant genotype strains such as PEDV G2 type KQ01 strain (the preservation number is CCTCC NO: V202005) and PoRV G9 type CH09 strain (the preservation number is CCTCC NO: V202191) are adopted as parent strains, a cell continuous passage method is adopted to carry out passage attenuation, and the virus content, the purity, the specificity, the hereditary stability, the safety and the immunogenicity are systematically inspected during the passage process; and then, carrying out proliferation process research on passage attenuated strains PEDV HB17-R and PoRV JS01-R in a bioreactor, harvesting a cell culture, mixing the two antigens according to a proper ratio, adding a proper amount of a stabilizer, and carrying out a freeze vacuum drying process to obtain the high-purity PoRV-HB17-R / PoRV-HB17-R / PoRV-HB17-R / PoRV-HB17-R / PoRV-JS01-R composite antigen. The bigeminy attenuated vaccine is highly matched with current dominant prevalent strains (PEDV G2 type and PoRV G9 type), is based on a suspension culture technology and has both safety and high efficiency.

The present disclosure provides a type A foot-and-mouth disease virus-like particle antigen assembled by VP2, VP3 and VP1 antigen proteins of an epidemic strain of type A foot-and-mouth disease virus. The type A foot-and-mouth disease virus VP2 antigen protein is encoded by a nucleotide sequence shown in SEQ ID No. 1 or its degenerate sequence, the type A foot-and-mouth disease virus VP3 antigen protein is encoded by a nucleotide sequence shown in SEQ ID No. 2 or its degenerate sequence, and the type A foot-and-mouth disease virus VP1 antigen protein is encoded by a nucleotide sequence shown in SEQ ID No. 3 or its degenerate sequence.

The invention discloses a porcine epidemic diarrhea virus G2c genotype strain as well as a separation method and application thereof. Aiming at the current epidemic PEDV variant strain, the genetic variation rule of the epidemic strain is clarified by carrying out virus separation, identification and pathogenicity analysis, and the method has important significance on epidemiology, vaccine development and the like of the PEDV. Specifically, an applicant successfully separates a PEDV strain capable of realizing stable passage propagation in Vero-CCL81 cells from intestinal contents of diarrhea piglets collected from a pig farm of Jiangpermanent Province in Hunan, the PEDV strain is identified and determined as a porcine epidemic diarrhea virus G2c subtype, the PEDV strain is named PEDV CH / HNJY / 2025, the PEDV strain is preserved in China General Microbiological Culture Collection Center on December 11, 2025, and the preservation number of the PEDV strain is CGMCC NO. The preservation number is CGMCC (China General Microbiological Culture Collection Center)

This invention belongs to the field of biomedical technology, specifically relating to a method for constructing a highly cell-adaptive PEDV GIIc recombinant chimeric virus. Specifically, this invention, based on the PEDV viral S protein determining PEDV's cell adaptability, innovatively elucidates that S2 is the key subunit determining its cell adaptability. On this basis, this invention proposes a scheme that can increase viral titer and thus reduce vaccine production costs when preparing candidate vaccine strains of circulating PEDV strains (especially GIIc). This involves retaining the S2 subunit of the highly cell-adaptive strain and replacing the S1 subunit of the highly cell-adaptive strain with the S1 subunit of the circulating strain, or replacing the S2 subunit of the circulating strain with the S2 subunit of the highly cell-adaptive strain. This scheme can both preserve the immunogenicity of the circulating strain and improve the efficiency of high-titer vaccine production.

The application provides a monoclonal antibody for specifically detecting rotavirus and an application thereof, and is directed to epidemic strains of porcine rotavirus, and refers to the gene sequence of VP6 protein published in GenBank, further optimizes an antigen epitope, obtains a purified recombinant VP6 protein with antigenicity, and performs animal immunization, and successfully screens the monoclonal antibody capable of specifically recognizing the porcine rotavirus. The monoclonal antibody screened can effectively recognize the epidemic strains, has the broad-spectrum recognition, is superior to the commercially available antibody, has high antigen recognition target specificity, is low in non-specificity, and has clear sequence background, can be scaled up and produced, and has good commercial value.

The application relates to the field of biological medicine, and provides a tetravalent antibody for neutralization of a novel coronavirus, which comprises an antibody monomer nAb and an scFv structure coupled at the Fc end of the heavy chain of the antibody monomer through a linker 1. Compared with the nAb antibody, the tetravalent antibody has higher antiviral capacity for various epidemic strains of the novel coronavirus, and has good application value.

The invention discloses a recombinant bacillus calmette-guerin vaccine for expressing O and A type multi-epitope fusion peptides of foot and mouth disease viruses and application of the recombinant bacillus calmette-guerin vaccine, and belongs to the field of biotechnology and veterinary vaccines. The amino acid sequence of the multi-epitope fusion peptide is shown as SEQ ID NO: 1, the multi-epitope fusion peptide comprises dominant immune T cell and B cell antigen epitopes from a plurality of O-type and A-type foot-and-mouth disease virus epidemic strains, and a mycobacterium signal peptide is fused at the N terminal. The recombinant strain rBCG-MIPGA is successfully constructed by carrying out codon optimization on the fusion gene, cloning the fusion gene to a pMV306 vector and carrying out electrotransfection on BCG. The recombinant BCG can simultaneously excite high-titer specific antibodies aiming at foot-and-mouth disease virus type O and type A and remarkable T cell immune response, shows lasting and broad-spectrum protection potential, and has great application value in the aspect of preparing safe, efficient and broad-spectrum foot-and-mouth disease vaccines.

The application provides a general avian infectious bronchitis virus whole genome deep sequencing method and application. The method realizes efficient amplification of long fragments of whole genomes of different genotype IBV epidemic strains by designing and applying a set of combinations containing 24 pairs of specific primers. The specific sequences of the primer combinations are shown in SEQ NO:1 to SEQ NO:48. Compared with a traditional sequencing method, the application significantly reduces the sequencing cost. Only two PCR reactions are needed, and more than 27 kb of IBV full-length genome sequence can be successfully obtained, which provides a more economical and efficient solution for IBV related scientific research and molecular epidemiology monitoring, and helps to promote the development of related field scientific research.

The application provides a pair of mouse monoclonal antibodies 4A5 and 2C12 with specific binding to canine rotavirus VP7 protein, and a colloidal gold detection kit prepared from the mouse monoclonal antibodies, which can detect various epidemic strains and standard strains of canine rotavirus with high sensitivity, has a high coincidence rate with an RT-PCR detection method, and can detect epidemic strains and target strains in different regions, has the advantages of rapidness, simplicity, accuracy, and can meet the urgent needs of the present clinical stage.

The application provides a primer probe combination for identifying the genotype of African swine fever virus, comprising a primer probe combination a for identifying a B646L gene, a primer probe combination b for identifying an MGF-110-5L gene and a primer probe combination c for identifying an I177L gene. The method for identifying the genotype of African swine fever virus by using the primer probe combination is as follows: extracting the genomic DNA of a sample to be detected, using the extracted genomic DNA of the sample to be detected as a template, performing a triple fluorescent quantitative PCR reaction by using the primer probe combination, and judging the genotype of African swine fever virus according to the fluorescent signal. The application also provides the application of the primer probe combination to the preparation of a kit for identifying the genotype of African swine fever virus. The concentration and reaction conditions of the primer probe combination are optimized, so that the designed primer probe combination has strong specificity, sensitivity and repeatability, not only solves the identification problem of African swine fever virus, but also simultaneously realizes the synchronous identification of three kinds of epidemic strain genotypes.

The invention relates to the technical field of biology, and particularly provides an influenza virus live vaccine as well as a preparation method and application thereof. The invention aims to solve the problems that influenza vaccines in the prior art generally face ineffective single immunization, cellular immune deficiency, insufficient broad-spectrum protection and high safety risk. Therefore, the invention provides an influenza virus live vaccine which comprises influenza virus which is not subjected to attenuation treatment. The influenza virus live vaccine disclosed by the invention breaks through the safety limitation of the traditional attenuated live vaccine, the fact that an unattenuated influenza epidemic strain (such as an H1N1 PR8 strain) can realize safe and efficient immune response through subcutaneous inoculation is proved for the first time, and a brand new technical path is provided for the development of influenza vaccines.

The invention relates to a multiplex fluorescent genotyping detection primer probe group and a kit aiming at a norovirus epidemic strain, and belongs to the technical field of biology. The primer probe group comprises a primer pair and a probe which are used for detecting the GII.17 type, the GII.3 type and the GII.4 type of the noroviruses; wherein the nucleotide sequences of the primer pair and the probe for detecting the GII.17 type are as shown in SEQ ID NO: 1-3; the nucleotide sequences of the primer pair and the probe for detecting the GII.3 type are as shown in SEQ ID NO: 4-6; the nucleotide sequences of the primer pair and the probe for detecting the GII.4 type are as shown in SEQ ID NO: 7-9. The method has the following technical effects: 1, the detection time is short, the operation is simple and convenient, and the total detection time is about 1.5 hours; 2, the sensitivity is high; 3, the detection limit is low, and the method can be applied to environmental specimen detection.

The invention relates to a duck infectious serositis pentavalent inactivated vaccine as well as a preparation method and application thereof. The vaccine is prepared from a duck infectious serositis type 1 antigen, a duck infectious serositis type 2 antigen, a duck infectious serositis type 6 antigen, a duck infectious serositis type 7 antigen and a duck infectious serositis type 10 antigen. The preparation method comprises the following steps: S1, strain screening; step S2, strain culture; step S3, carrying out inactivation treatment; step S4, bacterial liquid mixing; and S5, emulsifying the adjuvant. The duck infectious serositis pentavalent inactivated vaccine has the advantages of prominent broad spectrum, excellent immune effect and high industrial feasibility, can cover more than 90% of epidemic strains, solves the problem of incomplete prevention of the existing vaccine, has protection rates of more than or equal to 90% on the attack of five serotype virulent poison, adopts a fermentation tank for amplification culture in a culture process, has stable bacterial liquid proliferation efficiency, and is suitable for large-scale production. Emulsifying process parameters are clear and suitable for large-scale production.

The application provides a kind of construction and application of PRRSV live vector vaccine strain of recombination expression PEDV S protein receptor RBD domain, and the results show that the dominant antigen region of PEDV S protein RBD function domain can be expressed in the recombination virus rHuN4-F112-SRBD1 rescued, and the biological characteristics of recombination virus are similar to parent virus.The nucleotide sequence of SRBD1 gene introduced in each generation of recombination virus and the amino acid sequence encoded thereby are not deleted or mutated, and the IFA and Western Blot detection results show that the SRBD1 gene introduced in different generations of recombination virus rHuN4-F112-SRBD1 can be stably expressed, and does not affect the expression of parent virus itself protein, indicating that the recombination virus rHuN4-F112-SRBD1 strain has genetic stability.The immunogenicity analysis of recombination virus rHuN4-F112-SRBD1 shows that the recombination virus rHuN4-F112-SRBD1 strain can induce specific antibodies against PEDV S protein and PRRSV2 in piglets after immunization, and the antibodies induced have neutralizing effect on PEDV epidemic strain, and can be used for the development and development of PRRS and PED novel genetic engineering vaccine.

The invention discloses an avian leukosis tetravalent epitope mRNA vaccine and application, and belongs to the technical field of immunology and biology. According to epidemic strains of A, B, J and K subgroup avian leukosis viruses in recent 10 years, epitopes with relatively high antigenicity and conservative property in surface proteins (gp85 gene coding) are screened and connected in series, so that immune escape caused by self gene mutation of the avian leukosis viruses is avoided, the protection range is wider, and the kit has a good application prospect. And a molecular adjuvant is also added into an mRNA vaccine sequence to enhance the cellular immunity of the vaccine, so that the problem of low antigenicity of other vaccines is solved. Compared with purification investment, the vaccine has the advantages that the capital cost is saved by more than 50%, the consumption of time, manpower and material resources is greatly reduced, and the vaccine has a good application prospect.

The invention relates to the technical field of biology, and discloses an influenza A virus H5 protein mutant and application thereof. In order to solve the problems of weak cross immune response to epidemic strains, insufficient stability of wild type HA protein, low immunogenicity and the like of the existing H5N1 vaccine, a stable soluble H5 protein mutant is constructed through a sequence modification strategy. Specifically, the 332th to 380th amino acids in the HA protein of a wild type influenza A virus H5N1 are replaced by SPGCAT, and point mutations T386C, L418P and H456P are introduced to obtain the mutant. The mutant can significantly improve the structural stability of trimer protein, improve the expression level of recombinant protein, broaden the cross protection spectrum, enhance the level of immunogenic hemagglutination inhibition antibodies and improve immune response balance.

The invention belongs to the technical field of biology, and particularly relates to a PEDV (porcine epidemic diarrhea virus) reverse genetic operating system as well as a preparation method and application thereof. The construction method of the PEDV reverse genetic operating system comprises the following steps: constructing pBAC-M and pBAC-T; the method comprises the following steps: dividing a PEDV whole genome into 8 fragments, and amplifying and connecting the 8 fragments to a pcDNA3.1 vector by taking whole genome cDNA of a PEDV epidemic strain as a template; converting a connection product into escherichia coli, and culturing, so as to obtain pcDNA3.1-F1-F8; the method comprises the following steps: by taking pcDNA3.1-F1-F8 as a template, amplifying F1-F8 fragments, connecting the F1-F8 fragments to form a PEDV whole genome sequence, and inserting pBAC-M and pBAC-T to obtain pBAC-M-PEDV and pBAC-T-PEDV. The PEDV reverse genetic operating system provided by the invention provides support for research and development of PEDV vaccines.

The application discloses a general trimeric recombinant protein vaccine for preventing novel coronavirus infection. Specifically disclosed are a mutant protein RBD4M with an amino acid sequence of SEQ ID No. 1 and a fusion protein of positions 26-277, positions 1-277 and SEQ ID No. 4. The application also discloses a vaccine containing the fusion protein, and further develops a trimeric recombinant protein vaccine containing the fusion protein and a double adjuvant. Experiments show that the vaccine prepared in the application can effectively induce cellular immunity and humoral immunity of the body in animals, a trace amount of the protein can stimulate a very high immune response of mice, has a good protective effect, can produce high-titer neutralizing antibodies against various epidemic strains of the novel coronavirus, is a broad-spectrum effective novel coronavirus vaccine, and has important significance for preventing novel coronavirus infection and a wide clinical application prospect.

The invention relates to the field of veterinary biological products, and discloses a pigeon adenovirus type 1 and pigeon circovirus bivalent inactivated vaccine and a preparation method thereof. The virus strain which is good in immunogenicity, high in virus titer and good in virus purity and is screened from the separated and identified epidemic strains is used as the vaccine preparation strain of the pigeon adenovirus type 1 and pigeon circovirus bivalent inactivated vaccine. The pigeon adenovirus type 1 and pigeon circovirus bivalent inactivated vaccine has good immunogenicity, can well prevent diseases such as vomiting, diarrhea, weight loss, hepatosplenomegaly and the like caused by pigeon adenovirus and pigeon circovirus, and has 100% protection rate to local isolates. Research results of a production process, safety, immune evaluation and the like of the vaccine show that the vaccine is good in safety and stable in immune effect.

Provided are a polio vaccine and a method for preparing same. Immunization with vaccines made from poliovirus-like particles can induce high levels of neutralizing antibodies against poliovirus types I, II, and III, exhibiting broad-spectrum neutralizing activity against widely prevalent strains at present. The recombinant polio vaccine does not rely on live viruses. There are no live viruses involved in the vaccine production and testing processes, posing no biosafety risks or risks of inducing OPV vaccine-derived conditions. Also, the vaccine requires no high-grade facilities needed for the production and testing of IPV vaccines, which reduces the costs of production and quality control and improves the accessibility of the vaccine in mid- and low-income countries.

The invention belongs to the technical field of viruses and genetic engineering, and particularly relates to a respiratory syncytial virus (RSV) ON1 genotype epidemic strain, a fluorescent strain carrying enhanced green fluorescent protein (EGFP) and application of the respiratory syncytial virus ON1 genotype epidemic strain. According to the invention, a recombinant RSV ON1 epidemic strain based on an RSV ON1 genotype strain genome and a recombinant RSV ON1 fluorescent strain carrying an EGFP tag are constructed, and a key biological material and a genetic manipulation platform are provided for research on the virulence determinant of the RSV A subtype epidemic strain; the two recombinant RSV strains can be used for researching in-vitro virus replication mechanism and pathogenesis, neutralizing antibody immune escape, cell real-time fluorescence monitoring and the like, and a technical platform is provided for research, development and evaluation of RSV vaccines, antibodies, drug screening and the like.

An inactivated vaccine with the antigen content of 105.0 TCID50 / mL prepared by taking the separated FPV-BJ strain as an immunogen is used for immunization of kittens, a detectable antibody level appears in vivo and presents a rising trend on the 7 day after immunization, a high antibody titer is achieved for the first time on the 21 day, and a high antibody titer is achieved for the second time on the 28 day after secondary immunization. Compared with the prior art, the method has the advantages that the antibody level is greatly increased, the highest average antibody titer of an experimental group can reach 220.5, the complete protection on the existing prevalent strain, namely the FPV-BJ strain and other FPV strains separated by the method can be realized, and relatively, the traditional commercial vaccine cannot provide effective protection on the separated strains.

This invention relates to a primer and probe set and kit for multiplex fluorescent genotyping detection of norovirus strains, belonging to the field of biotechnology. The primer and probe set of this invention includes primer pairs and probes for detecting norovirus types GII.17, GII.3, and GII.4; wherein the nucleotide sequences of the primer pairs and probes for detecting GII.17 are shown in SEQ ID NO: 1-3; the nucleotide sequences of the primer pairs and probes for detecting GII.3 are shown in SEQ ID NO: 4-6; and the nucleotide sequences of the primer pairs and probes for detecting GII.4 are shown in SEQ ID NO: 7-9. This invention has the following technical advantages: 1. Short detection time and simple operation, with a total detection time of approximately 1.5 hours. 2. High sensitivity. 3. Low detection limit, applicable to environmental sample detection.

The invention discloses a disease-resistant cell strain, a section of amino acid sequence of M130 protein expressed in the cell strain is deleted to generate a new M130p.Ser1028Gly1041del protein type, the amino acid sequence of the M130p.Ser1028Gly1041del protein type is as shown in SEQ ID No: 28, and the cell strain has the capability of resisting PRRSV (Porcine Reproductive and Respiratory Syndrome Virus). The cell nucleus of the cell strain can be used as a donor to produce a disease-resistant cloned pig, and complete resistance to the current PRRSV epidemic strain is obtained. Through molecular design and a new editing method, natural mutation of animal endogenous genes is modified under the condition that the M130 endogenous protein space structure and the biological function are not affected, and the generated gene editing pig is better in health degree, high in cloning efficiency and higher in biological safety, and can be used for preparing the M130 endogenous protein. The method provided by the invention can be applied to the creation of novel materials for resisting the porcine reproductive and respiratory syndrome, such as large white pigs, landrace pigs, duroc pigs, Berkshire pigs, Hanpshire pigs and Pietrain pigs of different strains, and local pigs in China, and lays a foundation for breeding and popularization of porcine reproductive and respiratory syndrome resisting varieties.

The invention discloses an engineered exosome targeting delivery system (EMT-Cas12a) and application thereof in AIDS (acquired immune deficiency syndrome) treatment. The targeting delivery system is loaded with a functional component for cutting HIV (human immunodeficiency virus) previrus DNA (deoxyribonucleic acid) on the basis of CRISPR-Cas12a (clustered regularly interspaced short palindromic repeats). According to the targeting delivery system, a nano antibody Nb1 of targeting CD4 is expressed on the surface of EMT-Cas12a, so that the efficiency of targeting delivery of CRISPR-Cas12a to CD4 + cells is improved. According to the targeted delivery system, a multi-crRNA series strategy is designed, a conserved region shared by a targeted HIV-1 B subtype and Chinese epidemic strains (07BC, 08BC and B ') is conserved, the crRNA and Cas12a mRNA form a functional component for cutting HIV previrus DNA, the functional component and Cas12a mRNA are jointly packaged into EMT-Cas12a, and the risk of virus escape is reduced. According to the targeting delivery system, in cells cultured in vitro (cell lines infected with HIV-1 and PBMC derived from HIV-1 positive donors), and in vivo tests of intravenous injection of EMT-Cas12a in humanized mice infected with HIV-1, good biological safety characteristics and excellent antiviral efficacy are proved.

The invention discloses a preparation method and application of a GIIc type PEDV (Porcine Epidemic Diarrhea Virus) strain and a gastric acid resistant specific egg yolk antibody thereof, the PEDV strain is a GIIc type clinical predominant prevalent strain, and has good cell adaptability after plaque purification and domestication; the strain can be used for developing PEDV attenuated live vaccines, inactivated vaccines, novel genetic engineering vaccines, preventive and therapeutic antibodies and diagnostic reagents, and solves the technical problems that the existing vaccines are insufficient in protective power and the GIIc type PEDV clinical isolated strain is low in in-vitro culture titer; meanwhile, the invention discloses a core-shell nanoparticle antibody coating technology based on zein / carboxymethyl chitosan (Zein / CMCS), the PEDV egg yolk antibody IgY can be protected from being damaged by a strong acid environment and pepsase in the stomach of a pig, viruses in the intestinal tract are fully released and neutralized in the intestinal tract, PEDV infection is effectively prevented and treated, and the effect of preventing and treating porcine epidemic diarrhea is achieved. The problem that the neutralizing activity of the existing PEDV egg yolk antibody is sharply reduced after intragastric administration is solved.

The present application relates to the technical field of biology, and particularly provides an influenza virus live vaccine, a preparation method and application, aiming at solving the problems of single immunization invalidity, cell immunity loss, insufficient broad-spectrum protection and high safety risk of the influenza vaccine in the prior art. Therefore, the present application provides an influenza virus live vaccine, comprising an influenza virus without attenuation treatment. The influenza virus live vaccine of the present application breaks through the safety limit of the traditional attenuated live vaccine, and for the first time proves that the unattenuated influenza epidemic strain (such as H1N1 PR8 strain) can realize safe and efficient immune response through subcutaneous inoculation, thereby providing a brand-new technical path for the development of the influenza vaccine.

The invention discloses a multiple qPCR (quantitative polymerase chain reaction) detection kit for simultaneously detecting four fimbriae genes of swine pathogenic escherichia coli and application of the multiple qPCR detection kit. The kit comprises primers and a TaqMan probe, wherein the primers and the TaqMan probe are respectively used for detecting F4, F17, F18 and F41 fimbriae genes of swine pathogenic escherichia coli. Experiments prove that the kit has the advantages of low cost, high specificity, high sensitivity, rapidness and reliability in detection, simplicity in operation and the like when being used for detection. According to recent epidemiological investigation results, 951 pig anus swab samples are detected by using the method, 662 positive samples are detected, the positive rate is 69.61%, the sensitivity of the method is higher than that of conventional PCR, and the total coincidence rate of the two results is greater than 90%. The method is suitable for rapid molecular diagnosis of swine pathogenic Escherichia coli, is an effective technical means for screening the virulence gene of the swine pathogenic Escherichia coli epidemic strain, and fills the blank of multiple fluorescent PCR detection technology in the field.