80 results about "Viral type" patented technology

The invention provides a mutant of enterovirus 71 and virus-like particles thereof, and relates to the field of biological medicines. The enterovirus 71 type virus-like particle is obtained by modifying structural genes VP0, VP1 and VP3 of virus capsid protein by utilizing computational structure biology and completing self-assembly in vivo through a hansenula polymorpha expression system. Compared with the unmodified enterovirus 71 type mutant and the virus-like particles thereof, the enterovirus 71 type mutant and the virus-like particles thereof have the advantages that the immunogenicity can be obviously improved, and the clinical application prospect is relatively high.

The invention relates to the technical field of agricultural biology, and particularly provides a dsRNA nanocrystallization preparation for preventing and treating areca yellows as well as a preparation method and application of the dsRNA nanocrystallization preparation. Areca yellows are a destructive disease caused by areca symptomless virus type 1 (APV1), eight key target gene segments of an APV1 virus genome are screened, specific double-stranded RNA is designed, a nano-carrier is used for wrapping and delivering a dsRNA mixture obtained by transcription of the eight target gene segments, and the areca yellows are obtained by screening. And a nanocrystallization preparation for improving the environmental stability and RNA interference efficiency of the dsRNA is prepared. Experimental results show that the nanocrystallization preparation can effectively inhibit the key gene expression of APV1 virus, reduce the virus load and improve the resistance of areca catechu to yellows. The invention provides an accurate, efficient and environment-friendly biological prevention and control strategy, and has a wide agricultural application prospect.

The invention relates to a nucleic acid detection platform based on an SHERLOCK technology, which is used for diagnosing CAV-2. The SHERLOCK consisting of recombinase polymerase nucleic acid pre-amplification (RPA) and CRISPR-Cas13a is mainly used for specifically recognizing a conserved sequence of CAV-2RNA (Ribonucleic Acid) through crRNA (Complementary Ribonucleic Acid) so as to activate the non-specific'side cutting activity 'of lwCas13a, so that the report RNA is degraded. A real-time fluorescent quantitative PCR (qPCR) system or a lateral flow test strip is used for collecting fluorescent signals generated by cracking of the reporter molecules, and a visual result is displayed. In addition, through HUDSON treatment, RPA-CRISPR can be amplified at room temperature without viral nucleic acid extraction. The detection limit of the method is 1.1 * 10 < 2 > copies / [mu] L, and the method has no cross reaction with other canine infectious viruses. From sample collection to result output, the whole reaction of RPA-CRISPR can be completed within two hours, and the RPA-CRISPR kit is suitable for rapid test of clinical samples and can work well in the field or in primary laboratories. The method can get rid of the limitation of a detection instrument and complex operation, and is suitable for on-site rapid batch detection. The method is preliminarily verified and further optimized and applied.

The invention relates to the technical field of avian virus detection, and particularly discloses a primer probe combination, a kit and a method for simultaneously detecting chicken infectious anemia virus and chicken circle virus type 3 based on fluorescent RAA and application. The method can be used for simultaneously detecting the chicken infectious anemia virus and the chicken circle virus type 3, and has the advantages of simplicity in operation, short detection time, good specificity, high sensitivity, no need of expensive instruments and equipment, support of on-site rapid detection, suitability for large-scale popularization and application and the like; and effective technical support can be provided for rapid detection and screening of the chicken infectious anemia virus and the chicken circle virus type 3.

A CVB virus expression vector comprising a PIV5 W3A viral genome comprising a mutation at amino acid residue S157 or S156 of the P / V gene and a deletion of the small hydrophobic (SH) gene of the PIV5 W3A viral genome, wherein the amino acid substitution at amino acid residue S157 or S156 comprises a substitution of serine (S) with phenylalanine (F) or asparagine (N), and the SH gene has a deletion of the SH open reading frame or the entire SH gene transcription unit. The CVB virus expression vector expresses a heterologous polypeptide, including SARS-CoV-2 spike (S), and / or nucleocapsid (N) and / or membrane (M) proteins, RSV fusion protein (F), or other antigens.

The application provides a dengue virus protection and mosquito vector control antigen composition and application thereof. The antigen composition comprises a combination of dengue virus type 1-4 envelope protein domain III polypeptide and Aedes aegypti midgut mucin AaMuc1 antigen polypeptide; the amino acid sequences of the dengue virus type 1-4 envelope protein domain III polypeptide are respectively shown as SEQ ID NO. 1, SEQ ID NO. 2, SEQ ID NO. 3 and SEQ ID NO. 4; and the amino acid sequence of the Aedes aegypti midgut mucin AaMuc1 antigen polypeptide is shown as SEQ ID NO. 5. The prepared vaccine can induce the body to produce neutralizing antibodies against dengue virus type 1-4, achieve the protection of human body from dengue virus infection, induce the production of active antibodies targeting Aedes aegypti midgut mucin 1, inhibit and kill the dengue virus transmission vector Aedes aegypti, and achieve the dual prevention and control of dengue fever from two dimensions of infection prevention and transmission interruption.

The invention relates to the field of biological medicine, and provides a coxsackie virus A16 type mutant and a virus-like particle thereof, compared with a wild type coxsackie virus A16 type, the mutant has at least one amino acid mutation site in the following regions: (1) a canyon region of a virus capsid; (2) a channel area at a secondary axis; or (3) a channel region at a quasi-tertiary axis. The mutant and the virus-like particle are obtained by optimizing and modifying structural proteins VP0, VP1 and VP3 which form a virus capsid by using computational biology and structural biology methods, co-expressing and co-assembling the structural proteins in a hansenula polymorpha expression system to form the virus-like particle, and then carrying out series of chromatographic purification. Compared with a non-mutated coxsackie virus A16 type virus-like particle mutation scheme, the coxsackie virus A16 type virus-like particle mutation scheme disclosed by the invention has the advantages that the antigen immunogenicity can be obviously improved, and the clinical application value is realized.

The present invention relates to the field of biotechnology. The present invention provides a grass carp brain cell line sensitive to grass carp reovirus type II, which was deposited in the China Center for Type Culture Collection on October 19, 2024, with a deposit number of CCTCC NO: C2024101. The grass carp brain cell line constructed by the present invention shows remarkable stability and successfully achieved 60 stable passages. When inoculated with GCRV‑II, an atypical cytopathic effect can be exhibited. In addition, the grass carp brain cell line has the ability to efficiently replicate GCRV‑II, and even after three generations of blind transmission, the generated cytotoxin can still cause grass carp to become ill and die. Therefore, the present invention has laid a solid foundation for in-depth exploration of the pathogenic mechanism of GCRV‑II, vaccine development, and antiviral drug screening, which will help promote further progress in related research and provide a key cell model and research basis for the formulation of grass carp reovirus-related research and prevention and control strategies.

The present disclosure relates to a BCG based therapeutic agent using a BCG strain that overexpresses the STING agonist, c-di-AMP. This BCG strain, called BCG-disA-OE, enhances the elevated trained immunity of macrophages and promotes early anti-viral Type I interferon responses in a subject, providing protection against viral infections such as primary respiratory infections and SARS-CoV-2 infection.

The invention relates to key antigen epitope screening, in particular to an echovirus 18 type key antigen epitope peptide and application thereof. The result of an enzyme-linked immunosorbent assay shows that Epitope 1 (SEQ ID NO: 1) can be effectively combined with E18-VP1 antiserum, and the combining capacity is obviously higher than that of Epitope 2 in a blank control and a negative result, so that one antigen epitope peptide is screened based on the complete sequence of the echovirus 18-VP1, and the antigen epitope peptide has important guiding significance for research and development of echovirus 18 vaccines.

The invention discloses an application of alpha-lipoic acid in preparation of an anti-iridovirus drug. Related experiments show that alpha-lipoic acid can safely and effectively treat iridovirus such as frog virus type 3, not only can effectively reduce harm of iridovirus to frog and fish culture, but also can promote ecological high-quality development of aquaculture industry, and has obvious economic and social benefits.

The present application discloses a method for preventing and treating flue-cured tobacco virus disease, belonging to the field of plant protection. The method comprises (1) prevention: applying agents during the seedling stage, before transplanting, after transplanting, and during the field stage of tobacco growth; during the seedling stage: applying guanidine-copper acetate before thinning, replanting, and weeding; applying amino oligosaccharides and antiviral microbial agents before sealing the trays; applying cinclostrobin acetate solution after sealing the trays and before cutting the leaves; applying ningnanmycin and amino oligosaccharides before and after transplanting; applying insecticides mixed with plant resistance inducers, antiviral microbial agents, trace elements, and foliar fertilizers from one week after transplanting the seedlings to the stage of clustering; (2) treatment of the disease. The method prevents flue-cured tobacco virus disease by applying antiviral agents early in the whole growth stage of tobacco; and combining the antiviral agents with other specific agents to improve tobacco plant resistance, reduce the incidence of viral diseases, and improve the cure rate of viral diseases.

Described herein are systems and methods that may be used to differentially detect viral serotype specific nucleic acid. For example, these systems may comprise multiple DNA-nanostructures, capture oligonucleotides and protector oligonucleotides, wherein each DNA-nanostructure and its associated capture oligonucleotide and protector oligonucleotide are specific for a unique viral type or serotype.

The application provides a fusion protein, a rabbit hemorrhagic disease virus type 2 self-assembled nanoparticle vaccine and application, and belongs to the technical field of biological medicine. The application provides a fusion protein, which comprises a first polypeptide, a hinge region of a rabbit hemorrhagic disease virus type 2 capsid protein, a P region of a rabbit hemorrhagic disease virus capsid protein and a second polypeptide connected in sequence; the first polypeptide and the second polypeptide are polypeptides containing four cysteines respectively. The fusion protein RGD4C-HP-RGD4C of the application can self-assemble to form nanoparticles, and the particle size is 40-50 nm. The fusion protein of the application can induce domestic rabbits to produce specific antibodies against RHDV2, produce a strong humoral immune response, and provide complete protection for the domestic rabbits.

The invention discloses a grass carp reovirus type II mRNA (messenger Ribonucleic Acid) vaccine as well as a preparation method and application thereof, and belongs to the field of vaccines. According to the technical scheme, the grass carp reovirus type II mRNA vaccine comprises a modified mRNA chain, the modified mRNA chain sequence comprises a 5 'UTR sequence, a Kozak sequence, a grass carp immunoglobulin mu heavy chain signal peptide coding sequence, a GCRV II outer capsid protein VP35 coding sequence, three termination codons, a 3' UTR sequence and a polyA nucleotide sequence. The GCRV II mRNA vaccine is applied to enhancing the GCRV infection resistance of a fish body, the death rate is reduced, and the blank of the current grass carp reovirus II mRNA vaccine is filled.

The present invention provides an aminonitrothiazole derivative for use in the preparation of a drug for preventing and treating viral infections and related diseases caused thereto, and belongs to the field of pharmaceuticals. The structure of the aminonitrothiazole derivative is shown in Formula I. Experimental results show that the compound can effectively inhibit the activity of respiratory syncytial virus, enterovirus 71, and the new coronavirus, and the inhibitory effect is better than that of the positive controls nitazoxanide and lauric acid. The compound provided by the present invention can be used to prepare a drug for preventing and / or treating viral infections, and can be used to prepare a drug for preventing and / or treating related diseases caused by viruses, and has broad application prospects.

The invention belongs to the technical field of veterinary biology, and particularly relates to a swine foot and mouth disease virus O-type immune peptide fusion protein as well as a preparation method and application thereof. The invention provides a swine foot and mouth disease virus O-type immune peptide fusion protein. The swine foot and mouth disease virus O-type immune peptide fusion protein has an amino acid sequence as shown in SEQ ID NO: 1. The technical problems that in the prior art, antigen peptides adopted in FMDV-O immunization are insufficient in immunity and insufficient in protective efficacy are solved.

The invention belongs to the technical field of veterinary biology, and particularly relates to a swine foot and mouth disease virus type A immune peptide fusion protein as well as a preparation method and application thereof. The invention provides a swine foot-and-mouth disease virus type A immune peptide fusion protein. The swine foot-and-mouth disease virus type A immune peptide fusion protein has an amino acid sequence as shown in SEQ ID NO: 1. Compared with an epitope predicted in the prior art, the recombinant immune composite peptide provided by the invention has better immunogenicity, can obtain a neutralizing antibody with higher titer, and has better animal protection capacity.

The invention provides a fusion protein, a rabbit hemorrhagic disease virus type 2 self-assembled nanoparticle vaccine and application, and belongs to the technical field of biological medicine. The invention provides a fusion protein. The fusion protein comprises a first polypeptide, a hinge region of a rabbit hemorrhagic disease virus type 2 capsid protein, a P region of the rabbit hemorrhagic disease virus capsid protein and a second polypeptide which are connected in sequence, the first polypeptide and the second polypeptide are respectively polypeptide containing four cysteines. The fusion protein RGD4C-HP-RGD4C disclosed by the invention can be self-assembled to form nano particles, and the particle size is 40 to 50 nm. The fusion protein provided by the invention can induce a rabbit to generate a specific antibody aiming at RHDV2, generate a relatively strong humoral immune response and provide complete protection for the rabbit.

This invention relates to the field of biomedical technology, providing a rabbit hemorrhagic disease virus (RHDV) type 2 fusion antigen protein and its applications. The fusion antigen protein comprises the RHDV2 VP60 protein sequence and an immunomodulatory CRM197 protein functional fragment, fused together via a linker peptide, and expressed and purified in an insect cell expression system. This invention improves the immunogenicity of the antigen protein by fusing the major capsid protein VP60 of RHDV2 with the immunomodulatory fragment of CRM197. Rabbit immunization experiments verified that the fusion antigen protein can induce high-titer specific antibodies, with serum antibody titers reaching 1:12800 and above, demonstrating good immunization effects. The fusion antigen protein of this invention can be used to prepare a vaccine for the prevention of RHDV2 infection, providing a new technical solution for the prevention and control of RHDV2 disease.

The present disclosure relates to the field of biological medicine, and provides a mutant of coxsackievirus A16 and a virus-like particle thereof, wherein the mutant has at least one amino acid mutation site in the following regions compared with wild-type coxsackievirus A16: (1) a canyon region of a virus capsid; (2) a channel region at a dihedral axis; or (3) a channel region at a quasi-trihedral axis. The mutant and the virus-like particle are obtained by optimizing and modifying structural proteins VP0, VP1 and VP3 constituting the virus capsid by using computational biology and structural biology methods, co-expressing and co-assembling the structural proteins into the virus-like particle in vivo in a Hansenula yeast expression system, and then purifying the virus-like particle by serial chromatography. The mutation scheme of the coxsackievirus A16 virus-like particle in the present disclosure can significantly improve the antigen immunogenicity compared with the unmutated virus-like particle, and has clinical application value.

The invention relates to the technical field of viral vaccines, and particularly discloses a purification method of coxsackie virus 16. The invention discloses a method for purifying coxsackie virus 16, which comprises the following steps in sequence: pre-treating a virus ultrafiltration concentrated solution, and then carrying out ion exchange gel chromatography to obtain a virus purified solution; the pretreatment comprises the following specific steps: adding Triton-X100, trimethyl citrate and histidine into a virus ultrafiltration concentrated solution, and incubating for 2-4 hours at 10-18 DEG C; then adding glycerol, and incubating for 20-60 minutes at the temperature of 20-30 DEG C; the ion exchange gel chromatography adopts a flow-through process, and a Capto Q Impres gel medium is used for carrying out ion exchange gel chromatography. By means of the technical scheme, the separation efficiency of the coxsackie virus type 16 target product can be effectively improved, and the recovery rate of the coxsackie virus type 16 purified liquid product and the removal rate of impurity protein are guaranteed.

The application discloses a broad-spectrum neutralizing pig-derived monoclonal antibody of type A foot-and-mouth disease virus (FMDV) and application thereof. The antibody PAF56 has an amino acid sequence of a heavy chain variable region as shown in SEQ ID No. 12, a heavy chain CDR1 sequence of GFGFSNTY, a heavy chain CDR2 sequence of VFTGGGAT, and a heavy chain CDR3 sequence of VSNRDGFGGVGNV. The antibody PAF56 has an amino acid sequence of a light chain variable region as shown in SEQ ID No. 13, a light chain CDR1 sequence of SGSVTSLNY, a light chain CDR2 sequence of RTN, and a light chain CDR3 sequence of ALYKGSGTDTNI. The antibody PAF56 can simultaneously neutralize an AF72 strain of an A22 lineage and A / WH / CHA / 09 and A / GDMM / 2013 epidemic strains of a domestic SEA97 lineage, and has broad-spectrum neutralization activity of type A FMDV. The antibody PAF56 recognizes an antigen site 2 of a VP2 B-C loop, and a key amino acid is VP2 D72; the recognized site is highly conserved in type A FMDV. The application first obtains a broad-spectrum neutralizing antibody of type A specific FMDV from a natural host and identifies a key antigen site recognized by the antibody, thereby providing a powerful tool for antigen structure analysis of FMDV and establishment of a serological detection method.

The invention relates to the technical field of virus detection, in particular to a primer, a kit and a method for molecular traceability and variation analysis of dengue virus type I. The primer comprises an upstream primer and a downstream primer, the upstream primer and the downstream primer are both subjected to Tag and locked nucleic acid dual modification; the upstream primer has a nucleotide sequence as shown in SEQ ID NO 15; and the downstream primer has an amino acid sequence as shown in SEQ ID NO 16. The complete E gene sequence is obtained through sequencing after the complete E gene is subjected to RT-PCR amplification, time and labor are saved, the cost is low, and the complete E gene can be completely analyzed. The invention aims to establish an amplification primer capable of amplifying a complete E gene of the dengue virus type I (Den1) and a kit comprising the amplification primer, an amplification reagent and the like, sequencing an amplification product, and further performing molecular traceability and virus variation analysis on the virus.

The application discloses a dengue virus armored RNA standard substance and a preparation method and application thereof, and belongs to the technical field of virus detection. The dengue virus armored RNA standard substance comprises a virus-like particle shell formed by self-assembly of capsid proteins of phage MS2 and an internal encapsulated dengue virus 3' untranslated region partial sequence fragment; and the nucleotide sequence of the dengue virus 3' untranslated region partial sequence fragment is shown as SEQ ID NO: 2. The dengue virus armored RNA standard substance provided by the application can be used for nucleic acid detection of dengue virus with the dengue virus 3' untranslated region partial sequence as a target. The standard substance has the characteristics of stable property, no biological pollution, true simulation of virus particle structure and RNase resistance, and is suitable for quality control of nucleic acid detection methods with the dengue virus (type 1-4) 3' untranslated region as a target, and evaluation of detection reagents and laboratory capacity.

This invention provides an attenuated vaccine against Coxsackievirus A6 (CVA6), its preparation method, and its application. By comparing a highly pathogenic clinical isolate (CVA6-HeB) with an attenuated strain (CVA6-TW141), the genetic basis of CVA6 virulence was systematically studied. This invention located the core virulence determinant to the P1 capsid region and identified a key lethal amino acid residue (VP3-238) that significantly weakens viral replication in target tissues. Based on this discovery, this invention designed and validated a candidate attenuated live vaccine with significantly reduced lethality.

The application discloses a foot-and-mouth disease virus type A ELISA antibody detection kit and a preparation method and application thereof. The application determines a sequence of a foot-and-mouth disease virus type A GH loop epitope polypeptide and a non-specific combination of a foot-and-mouth disease virus type O, effectively solves the non-specific combination problem through sequence reduction, obviously reduces the detection sensitivity of the type A antibody after the reduction, further improves the detection sensitivity through a form of a multi-antigen peptide to display the polypeptide sequence. Finally, the polypeptide epitope combination, the antigen coated plate containing the polypeptide epitope combination and the ELISA antibody detection kit are determined. The total coincidence rate of the kit for detecting foot-and-mouth disease inactivated vaccine immune antibodies and negative serum is as high as 95% or more, but the positive detection rate of the kit for detecting foot-and-mouth disease synthetic peptide vaccine immune antibodies is obviously improved, and the cross reaction of the kit for detecting foot-and-mouth disease virus type O vaccine and pig foot-and-mouth disease virus type O inactivated vaccine immune antibodies is effectively reduced.

This invention discloses a primer and nucleic acid mass spectrometry method for detecting dengue virus genotypes 4 based on multiplex RT-PCR, belonging to the field of gene detection service technology. The primer set includes amplification primer pairs and extension primers. The amplification primer pairs include upstream and downstream primers specific to the poly genes of dengue virus types 1-4, with sequences shown in SEQ ID NO. 1-8, respectively. The extension primers include extension primers targeting specific sites of dengue virus types 1-4, with sequences shown in SEQ ID NO. 9-12, respectively. The nucleic acid mass spectrometry method of this invention includes: nucleic acid extraction, multiplex RT-PCR amplification and enrichment, SAP purification reaction, extension reaction, desalting treatment, and mass spectrometry detection. This invention not only utilizes the high throughput and high precision advantages of nucleic acid mass spectrometry technology, but also provides a new, efficient, accurate, and reliable dengue virus genotyping detection scheme through targeted primer design and systematic process integration, providing a powerful technical tool for the accurate diagnosis, epidemic monitoring, and prevention and control of dengue fever.

The invention belongs to the technical field of molecular detection, and particularly relates to an RPA primer, a probe, a kit and a method for rapidly detecting adenovirus type 4. The RPA primer comprises a forward primer and a reverse primer, the sequence of the forward primer is as shown in SEQ ID No.1, the sequence of the reverse primer is as shown in SEQ ID No.2, and the sequence of the RPA-LFD probe is as shown in SEQ ID No.3. According to the method, the primers and the probe are applied, so that the method has the characteristics of good specificity, high sensitivity, simplicity, rapidness, high efficiency and the like, the requirement of rapid detection in a farm can be met, the detection efficiency is improved, and a new technical support is provided for rapid detection of the chicken adenovirus.

The present invention provides a human enterovirus 71 VP1 protein-specific binding polypeptide, its preparation method and application, and belongs to the field of molecular biology technology. The amino acid sequence of the polypeptide is HNWMWYASLPDR. In response to the problem that existing hand, foot and mouth disease diagnostic and therapeutic drugs are not specific, the present invention uses the important capsid protein VP1 of human enterovirus 71 as the target molecule, and obtains a polypeptide by biopanning a phage display random 12-peptide library. The phage ELISA experiment shows that the polypeptide can specifically recognize and bind to the EV71 virus VP1 protein, has a small molecular weight, is easy to chemically synthesize, and has low immunogenicity. The successful preparation of this polypeptide has good application prospects in the research and development of products such as hand, foot and mouth disease diagnosis, treatment, and prevention.