54 results about "Structural Protein Gene" patented technology

Chimeric flaviviruses that are avirulent and immunogenic are provided. The chimeric viruses are constructed to contain amino acid mutations in the nonstructural proteins of a flavivirus. Chimeric viruses containing the attenuation-mutated nonstructural genes of the virus are used as a backbone into which the structural protein genes of a second flavivirus strain are inserted. These chimeric viruses elicit pronounced immunogenicity yet lack the accompanying clinical symptoms of viral disease. The attenuated chimeric viruses are effective as immunogens or vaccines and may be combined in a pharmaceutical composition to confer simultaneous immunity against several strains of pathogenic flaviviruses.

The invention discloses a multi-epitope fusion diagnosis antigen for African swine fever virus as well as a preparation method and application thereof. An ASFV (African swine fever virus) important structural protein gene encoding amino acid sequence is analyzed, screened and recombined through bioinformatics software, a multi-epitope fusion antigen gene is built and synthesized and is expressed in bacillus coli; through screening, the recombinant multi-epitope fusion antigen ASFV-meAg6 is obtained, so that diagnosis antigen protein with strong specificity and high sensitivity is provided foran ASFV serological diagnosis method.

The invention provides a cDNA (complementary Deoxyribonucleic Acid) infectious clone of a porcine reproductive and respiratory syndrome virus vaccine strain and application thereof, and discloses a recombinant vector, which is an infectious clone of a porcine reproductive and respiratory syndrome virus vaccine strain CH1R constructed by adopting a reverse genetics approach. The infectious clone comprises a full-length gene cDNA sequence of the porcine reproductive and respiratory syndrome virus vaccine strain CH-1R. The invention further discloses an artificially cloned attenuated vaccine strain, which is a cloned strain of the porcine reproductive and respiratory syndrome virus vaccine strain CH-1R, wherein a marked restriction enzyme locus is introduced in a structural protein gene sequence. Through performing genetic engineering reconstruction of the infectious clone, a better vaccine can be researched, and the prevention and control of the porcine reproductive and respiratory syndrome are facilitated.

The invention relates to pichia pastoris for expressing rotavirus expression particles as well as a preparation method and application of the pichia pastoris, and discloses a human rotavirus structural protein expression cassette, comprising the following elements: (a) an initial signal element AOX; (b) a rotavirus structural protein gene; and (c) a termination signal element TT. The invention further discloses a yeast cell transfected by using the expression cassette, a method for preparing the rotavirus viroid particles by using the yeast cell, viroid particles prepared by using the method, and application of the viroid particles for preparing vaccine compositions for preventing or treating rotavirus infection. The invention also discloses a preparation method of the yeast cell.

This invention discloses a medicament carrier for targeted medicament delivery on diseases related to macrophage and a preparation method thereof, the medicament carrier is hollow virus-like particles formed by prokaryotic expression and self-assembly of rotavirus coat protein Vp6 with specific identification ability to the macrophage; the internal surface or the external surface of the medicament carrier is chemically modified with medicament molecules. The preparation method comprises the following steps: firstly, extracting genes of structural protein Vp6 of A group rotavirus; secondly, cloning the genes of the structural protein Vp6 to a prokaryotic expression carrier; thirdly, performing expression in colibacillus BL21; and finally, crosslinking the expressed protein with the medicament and performing assembly to obtain the virus-like particles. By using the specific identification ability of the virus-like particles to the macrophage, medicaments are delivered to the macrophage to realize the functions of the targeted medicament delivery and slow release. The medicament carrier of the invention can effectively reduce the dosage and toxicity of the medicaments, prevent the medicaments from being degraded by internal environment, improve treating effect, and realize mass production and reduce manufacture cost at the same time.

The invention discloses a screening method of a cell line capable of stably expressing a complete structural protein CHO-K1 of a hog cholera virus, which mainly comprises the following steps: amplifying a complete structural protein (ShmEs) gene of the hog cholera virus (a rock gate strain) by utilizing a PCR (Polymerase Chain Reaction) method, and inserting the gene into an eukaryotic expression vector pcDNA3.4 to construct a recombinant expression plasmid pcDNA3.4-ShmEs. A transient transfection method is used for transferring the recombinant plasmid into CHO-K1 cells, and antibiotic G418 is used for screening. Test results show that the ShmEs gene is expressed in CHO-K1 cells and can be stably transmitted, and antigen immunized rabbit bodies produced by the stable cell line can stimulate the rabbit bodies to generate swine fever specific antibodies, and the swine fever specific antibodies can be maintained for at least 42 days. The successful expression of the ShmEs gene and the establishment of a stable cell line of the ShmEs gene lay a foundation for the development of novel genetic recombinant vaccines for swine fever.

The invention discloses the cDNA sequences of the non-structural protein gene NS1 of avian influenza virus, its preparation process and use, wherein gene is employed for constructing prokaryotic expression vectors, the expression vectors are transformed into bacillus coli to obtain recombinant strains (Escherichia coli BL21 / pET-28a-NS1), the strains are utilized to express the non-structural protein NS1 of the avian influenza virus, the expression proteins are used to establish a differential diagnosis method through enzyme linked immunosorbent assay for differentiate vaccinum avian influenzae inactivatum immune chicken from infected chicken. The invention also relates to a differential diagnosis reagent kit and its application.

The invention discloses a recombinant vaccine with canine adenovirus type-2 as a live vector for displaying a protective antigen of rabies virus, which relates to recombinant vaccines displaying the protective antigen or an antigenic epitope of the rabies virus respectively by utilizing the characteristics of different structural proteins of the canine adenovirus type-2. The protective antigen ofthe rabies virus or a ribonucleotide sequence expressing the antigenic epitope are inserted at a hydrophobic locus of a structural protein gene to ensure that an exogenous antigen or an antigenic epitope is subject to fusion expression with structural protein of the exogenous antigen or the antigenic epitope on the surfaces of adenoviruses. After the recombinant vaccines challenge, test animals are subject to closed and isolated rearing, feeding and disease conditions of the test animals are observed and recorded; and the results show that dogs taking any kind of recombinant vaccine by oral administration and intramuscular injection all can resist the attack of strong viruses, and the survival rate is more than 90 percent.