68 results about "Infectious bursal disease virus IBDV" patented technology

The present invention belongs to molecular immunology field, mainly relating to chicken infectious bursal disease virus IBDV VP2 polypeptide fragment, more specificly relating to B cell antigen epitope polypeptide fragment in VP2 protein. The present invention also relates to IBDV VP2 protein neutrality and uses of B cell antigen epitope in preparing immunogen, immune animal, immune protection and uses for detecting antibody of resisting chicken infectious bursal disease virus IBDV or polypeptide of chicken infectious bursal disease virus IBDV. Animal is immunized by immunogen or vaccine designed according to B cell antigen epitope which can neutralize chicken IBDV VP2 protein and can produce antibody for neutralizing IBDV in vitro or vivo, so the immunogen can prevent virus infection to animal. Chicken IBDV VP2 protein neutralized B cell antigen epitope vaccine can prevent infection of chicken IBD classic toxic strain, superstrong toxic strain or/ and variant toxic strain.

The invention relates to virus-like particle recombinant protein of a virus variation strain VP2 gene of an infectious bursal disease, belonging to the field of biologic pharmacy. The IBDV variation strain (AH1) VP2 gene is cloned, converted and transfected to obtain a recombinant baculovirus vBac-VP2; an infected Sf9 insect cell has specific fluorescence, and the antigen valence of the infected Sf9 insect cell is above 1.6*10<3>; the molecular weight of a recombinant VP2 protein is 53kDa, and the recombinant VP2 protein is in the state of virus-like particles; an indirect ELISA detection method established for an envelope antigen by the purified recombinant VP2 protein has good specificity and sensibility; an immune chicken can resist IBDV virulent attack, and the protection ratio achieves 100 percent. The novel virus-like particle recombinant VP2 protein prepared by the IBDV variation strain VP2 gene has high pertinence on the immune prevention of a current prevalent IBDV virulent strain and good practical value and popularization prospects.

The invention provides an anti-chicken infectious bursal disease (IBD) recombinant protein subunit vaccine. The vaccine is a fusion protein having high immunogenicity of Salmonella typhimurium flagellin and an infectious bursal disease virus (VP2). The above flagellin + VP2 fusion protein is obtained through the expression of a recombinant baculovirus containing a flagellin + VP2 gene by utilizing a Bac-to-Bac baculovirus expression system. The recombinant baculovirus obtained through the system has a short period, and the expressed flagellin + VP2 fusion protein has high immune protection force.

The invention relates to a method for producing a quadruple inactivated vaccine for newcastle disease, infectious bronchitis, avian influenza (H9 subtype) and infectious bursal disease. In the method, the inactivated vaccine is prepared by adopting a newcastle disease virus La Sota strain, an infectious bronchitis virus M41 strain, an avian influenza virus (H9 subtype) YBF003 strain, and an Escherichia coli genetic engineering bacteria E. coil BL21/pET28a-VP2 strain which expresses an infectious bursal disease virus VP2 protein serving as production bacteria toxic species, a super concentration process and a high-quality adjuvant. After immunizing animals, antibodies are produced rapidly; the potency is high; the protection period is long; and the outbreak and the spreading of epidemic diseases are reduced.

The invention discloses a visual protein chip for detecting serum antibody of new-castle disease virus of chickens, infectious bronchitis virus of chickens, avian influenza virus and infectious bursal disease virus of chickens , which is prepared by the following steps: purifying and diluting whole proteins of the four virus respectively; pointing samples of the positive control serum, the negative control serum and the four virus proteins onto a chip carrier respectively; drying, fixing, sealing and washing the samples to obtain the visual protein chip. The visual protein chip uses the purified whole proteins as capturing antigens to detect the virus-specific antibodies in chicken serum so as to simplify the preparation technology and reduce the production cost, and the visual protein chip has better specificity but no cross, has high reliability of results and has the advantages of quickness, simplicity and convenience, high sensitivity, good specificity and the like. When the serum is diluted by 6,400 times, the visual protein chip still can detect the antibodies, the sensitivity is 400 times of that of the prior AGP detection method. According to the detection to serum samples in-place, the detection rate of the visual protein chip is higher than the proir AGP method remarkably.

The invention discloses an infectious bursal disease virus strain A11 and application thereof, and belongs to the field of the microbial technology. Infectious bursal disease viruses are separated from infectious bursal disease vaccine immunity failure chicken flocks appearing in recent years, biological characteristic analysis is carried out on obtained virus isolate strains, and the infectious bursal disease virus strain A11 with good biological characteristics is screened out from the obtained virus isolate strains and is a currently-popular infectious bursal disease virus with super-strong virulence. The virulence of the virus is attenuated with a chicken embryo and cell continuous passage method to culture the low-virulence strain A11, the low-virulence strain A11 has super-strong reproductivity in cells, the virus yield in cells reaches up to 10<11> TCID50/0.1 ml, immune protection resisting infectious bursal disease viruses can be rapidly generated by immunizing chicks with the strain A11, immune protection can be achieved after 1 week, and the strain A11 has huge application value in developing new specific infectious bursal disease vaccines.

The empty capsids of the infectious bursal disease virus (IBDV) are formed by the assembly of proteins derived from the pVP2 protein of IBDV, with a different size and with an application in producing vaccines and in preparing gene therapy vectors.

The invention discloses a recombinant yeast strain for expressing chicken IBDV (infectious bursal disease virus) VLPs (virus-like particles), a protein expressed by the recombinant yeast strain and an application. The recombinant yeast strain contains an optimized chicken IBDV VP2 gene sequence and can efficiently express a VP2 protein, and the expressed recombinant VP2 protein can be self-assembled into the VLPs. A vaccine is prepared from the chicken IBDV VLP protein expressed by the recombinant yeast strain to immunize chickens, and an experiment result indicates that the subunit peptide vaccine can effectively induce organisms to produce specific humoral immune response, so that the immunized chickens acquire 100% resistance to highly pathogenic vv IBDV fatal attack, residual viruses in the organisms can be cleared, and the purpose of sterilizing immunity is achieved. Therefore, one novel technical means is provided for prevention and control of chicken infectious bursal disease.

The invention relates to a production method of a newcastle disease (ND), infectious bronchitis (IB), infectious bursal disease virus (IBD) and viral arthritis (VA) four-joint inactivated vaccine. The production method is characterized by comprising the following steps: adopting ND La Sota strains, IB virus M41 strains, E.coli BL21/pET28a-VP2 strains expressing the IBD virus VP2 protein and VA AV2311 strains as bacterial and viral strains and adopting a superstrong concentration process and high-quality adjuvants to prepare the inactivated vaccine. After being used for immunizing animals, the inactivated vaccine has the characteristics of high antibody production speed, high titer and long period of protection, and can be used for reducing the epidemic disease occurrence and spreading.

The chimeric empty capsids of the infectious bursal disease virus (IBDV) are constituted by assembly of (i) IBDV pVP2 proteins and (ii) fusion proteins comprising a region A constituted by the IBDV VP3 protein bound to a region B constituted by a heterologous polypeptide comprising a polypeptide of interest, such as a polypeptide useful in vaccination, therapy or diagnosis.

The invention relates to the technical field of biology, and particularly provides a fusion protein of an infectious bursal disease virus, a preparation method, application, an expression system of the fusion protein and a vaccine comprising the fusion protein. The fusion protein comprises a VP2 section and a VP3 section, wherein the VP2 section is expressed by a nucleotide sequence shown in SEQ ID NO.1, the VP3 is expressed by a nucleotide sequence shown in SEQ ID NO.2. The fusion protein is obtained by tandem expression of the gene sequences of the VP2 and the VP3 of the infectious bursal disease virus. By analyzing the gene sequences of the VP2 and the VP3 and selecting zones high in antigenicity and easy for high expression to link tandemly, the obtained fusion protein has the advantages of high antigenicity and high expression amount. By adopting the fusion protein as an antigen to prepare the vaccine, the prepared vaccine has the advantages of good safety, stable potency and no toxic and side effects. The invention further provides the preparation method and application of the fusion protein, and the vaccine prepared from the fusion protein.

Methods of identifying animals infected with a vvIBDV are provided. The methods comprise contacting a nucleic acid sample obtained from the animal or a nucleic acid product obtained by amplifying RNA obtained from the animal with one or more probe pairs, each of which comprises a mutation probe and an anchor probe, and then determining the melting temperature of any hybridization complex that is formed when the one or more probe pairs hybridize with a nucleic acid in the sample. Such determination is made using FRET analysis. In one embodiment the mutation probe comprises a sequence identical to a first mutated target sequence of SEQ ID NO: 1 in which the cytosine at position 827 is substituted with a thymidine, the cytosine at position 830 is substituted with a thymidine, and the thymidine at position 833 is substituted with a cytosine, or the reverse complement thereof. In another embodiment, the mutation probe comprises a sequence identical to a second mutated target sequence of SEQ ID NO: 1 in which the guanine at position 897 is substituted with an adenine, the cytosine at position 905 is substituted with a thymidine, and the cytosine at position 908 is substituted with an thymidine. Also, provided herein are kits containing nucleotide probe pairs that can be used in the present methods.

The present invention relates to an infectious bursal disease live vaccine production method, which screens virulent strains with good immunogenicity, wider antigen spectrum and immune synergy from studies of characteristics of different infectious bursal disease virus such as immunogenicity, antigen spectrum, pathogenicity of bursa of Fabricius and capacity of breaking through maternal antibody, carries out development of the infectious bursal disease trivalent live vaccine, and develops a live vaccine--an infectious bursal disease trivalent live vaccine which has good immunogenicity, can break through higher level maternal antibody, has long immune duration more than 3 months, and has good protection to the various virulent strains.

The invention discloses an attenuated infectious bursal disease virus, which has a preservation name of: infectious bursal disease virus IBDV/1F, and is preserved in China Center for Type Culture Collection at Wuhan University in Wuhan, China. The preservation number is CCTCC NO: V201834, and the preservation date: July 3, 2018. The invention also provides the use of the attenuated infectious bursal disease virus in preparation of vaccines. The viral strain does not cause bursal damage in chickens and can induce high titer antibodies directed at infectious bursal disease virus. The vaccine canresist the attack of virulent strains and has no influence on the development of chickens.

The invention relates to a production method of a triple inactivated vaccine for newcastle disease, infectious bursal disease and viral arthritis. In the invention, the method adopts newcastle disease virus La Sota strain, escherichia coli genetically engineered bacteria E.coli BL21/pET28a-VP2 strain expressing chicken infectious bursal disease virus VP2 protein as well as viral arthritis AV2311 strain as the bacteria producing virus seeds; and the inactivated vaccine is prepared by use of super concentration technology and high-quality adjuvant. After animal immunization, the antibody is quickly produced; and the inactivated vaccine has high titer and long protection term, and reduces the occurrence and propagation of pestilence.

The present invention relates to a novel method to detect and differentiate different strains of infectious bursal disease virus (IBDV) in a chicken and other bird sample. RNA was obtained from said samples by using a pair of primer (Primer FVVC & RVVC) in a reverse transcriptase-polymerase chain reaction. Two different primer combinations (Primer IF & IVIR) and (Primer IF & RCLA) and real-time polymerase chain reaction conditions were designed and optimized for rapid differentiation of very virulent and vaccine strains of IBDV based on detection of signatory threshold cycle (Ct) and melting temperature (Tm) values.

The invention provides a visual gold-labeled silver staining gene chip. The chip can be used for simultaneously detecting at least one of avian leukosis virus, Marek's disease virus, infectious bursaldisease virus, newcastle disease virus, avian influenza virus and infectious laryngotracheitis virus. The invention also provides a detection method of the avian leukosis virus, the Marek's disease virus, the infectious bursal disease virus, the newcastle disease virus, the avian influenza virus or the infectious laryngotracheitis virus. The method is realized by utilizing the chip. The method has the advantages of low cost, simplicity in operation and high flux, and has a wide application prospect in the field of avian virus detection.

The invention discloses a bivalent subunit vaccine of Newcastle disease and infectious bursal disease, and belongs to the field of veterinary biological products. The subunit vaccine is prepared by taking Newcastle disease virus-like particles and infectious bursal disease virus-like particles as antigens, infecting insect cells by recombinant baculoviruses (rBV-NDV-HN+F+M and rBV-IBDV-doubleVP2),and performing purifying and inactivating. The subunit vaccine provided by the invention can rapidly generate specific antibodies, and can be used for preventing infection of Newcastle disease virusand infectious bursal disease virus. Experiments show that the subunit vaccine provided by the invention has better immune protection efficacy compared with commercial vaccines in preventing infectionof a Newcastle disease virus virulent strain and infection of infectious bursal disease virus.

The invention belongs to the field of genetic engineering in the biotechnological pharmaceutical industry, and particularly relates to infectious bursal disease virus VP2 protein as well as an encoding gene and application thereof. An amino acid sequence of the infectious bursal disease virus VP2 protein is as shown in SEQ ID NO:2. A base sequence of the encoding gene of the infectious bursal disease virus VP2 protein is as shown in SEQ ID NO:1. The infectious bursal disease virus VP2 protein disclosed by the invention well utilizes the advantages of VP2 and Pichia pastoris, and the encoding gene of the infectious bursal disease virus VP2 protein can be efficiently expressed in the Pichia pastoris, so that the production cost is reduced; and the application of the recombinant protein in preparation of infectious bursal disease vaccines has very high economic value and huge social benefit.

The invention provides chicken infectious bursal disease virus VP2 protein and a preparation method and application thereof and a kit. Particularly, a nucleotide sequence for coding the VP2 protein contains the sequence as shown in SEQ ID No.1. The method for preparing the VP2 protein comprises the following steps of chemically synthesizing the SEQ ID No.1 sequence, constructing an expression vector and transfecting sf9 cells. The VP2 protein can be used for preparing a vaccine for a chicken infectious bursal disease. The SEQ ID No.1 is obtained by conducting codon optimization on a chicken IBDV VP2 gene according to insect cell preference codon, and therefore compared with a general VP2 gene which is amplified from an IBDV virus, the SEQ ID No.1 is more suitable for being expressed in insect cells and can increase the protein expression quantity.

The present invention relates to the linear ligand epitope of Bursal bursal virus and its specific application. The polypeptide P22 on the IBDVVP2 protein is synthesized, and the CEF is used as the target cell. Through the infection and harvest of IBDV, the virulence and half tissue culture of IBDV are measured. Infection dose and infection ratio, the combination test of synthetic polypeptides and target cells, the virus blocking test and the test of polypeptide blocking IBDV infection target cells, the screened specific binding target cells can inhibit virus infection ligand epitope polypeptides, and The ligand epitope of IBDV was precisely mapped. The polypeptide P22 of the present invention can inhibit IBDV from infecting CEF, and with the increase of polypeptide concentration, the infection rate of CEF decreases in a dose-dependent manner. When the polypeptide concentration is 0.2 mmol/L, it can completely inhibit IBDV from infecting CEF target cells. The invention provides a theoretical basis for further research on the virus ligand epitope from the aspect of the interaction between the virus ligand and the virus receptor.

The present invention belongs to the field of molecular immunology, mainly relates to series polypeptide fragment of chicken infective Fabricius bursa disease virus IBDV VP2 protein, in particular, it relates to polypeptide fragment series formed into B cell antigen apitope in VP2 protein. After the animal body is immunized by immunogen or vaccine designed by utilizing the invented chicken infective Fabricius bursa disease virus IBDV VP2 protein neutrality B cell antigen epitope, the neutrality antibody for IBDV can be produced, and can neutralize IBDV in vivo or in vitro, and can prevent the virus from infecting animal body.

The invention discloses a super-high virulent chicken infectious bursal disease virus cell adapted strain, the preservation number thereof is CCTCC NO: V201316, and application of the super-high virulent chicken infectious bursal disease virus cell adapted strain in preparation of a chicken infectious bursal disease virus vaccine, an antigen reagent for diagnosis, a positive serum reagent for diagnosis, an egg yolk antibody for therapy, and antiserum. The chicken infectious bursal disease virus CL40 strain of the invention has super-high epidemic strain character, has good immunogenicity, and is suitable for cell scale cultivation. The TCID50 of the chicken infectious bursal disease virus CL40 strain is 10<-8.0>/0.1ml, and has a 100% protection rate to the fetal attack of the super-high strain IBDV-CL, and is stable in immunity effect, long in duration time, and has important value for preventing and controlling chicken infectious bursal disease super-high virus prevalence.

The invention discloses a chicken infectious bursal disease virus novel variant strain subunit vaccine and preparation method and application thereof. According to the vaccine and the preparation andthe application thereof, aiming at prevalence of an IBDV novel variant strain, a gene expression cassette of main protective protein VP2 of an IBDV novel variant strain representative strain SHG19 isdesigned, an element facilitating correct conformation formation of the gene expression cassette is introduced, recombinant prokaryotic expression plasmids are constructed, recombinant escherichia coli genetically engineered bacteria are prepared, through exploration of expression conditions and purification conditions, an IBDV novel variant strain virus-like particle is efficiently prepared, thevirus-like particle and adjuvant are emulsified to prepare the vaccine, and the test results show that the vaccine provides 100% immune protection for the homologous novel variant strain, and providesgood immune protection for the lethal attack of heterologous vvIBDV. The invention provides an effective technical means for the prevention and treatment of the the IBDV novel variant stain and a supervirulent strain.

The invention discloses a preparation method and a product of a chicken infectious bursal disease virus antigen. A chicken infectious bursal disease virus VP2/4/3 polyprotein gene and a VP2 gene are optimized. The optimized chicken infectious bursal disease virus VP2/4/3 polyprotein gene or the VP2 gene is expressed in a silkworm bioreactor. The invention further discloses a preparation method of a chicken infectious bursal disease nucleic acid vaccine. The preparation method comprises the following steps: cloning the optimized chicken infectious bursal disease virus VP2/4/3 polyprotein gene or the VP2 gene into a baculovirus transfer vector controlled by a mammal promoter to be recombined with baculovirus to infect an insect host, presenting an exogenous gene in the insect host to obtain the nucleic acid vaccine. The expressed antigen is used for preparing a vaccine for immunizing animals or the nucleic acid vaccine is used for immunizing animals through injection or oral taking, so that effective immune protection is provided for the animals.