CN117448355A - Recombinant DNA molecule for encoding coronavirus antigen, DNA vaccine and application - Google Patents

Recombinant DNA molecule for encoding coronavirus antigen, DNA vaccine and application Download PDF

Info

Publication number
CN117448355A
CN117448355A CN202210874769.0A CN202210874769A CN117448355A CN 117448355 A CN117448355 A CN 117448355A CN 202210874769 A CN202210874769 A CN 202210874769A CN 117448355 A CN117448355 A CN 117448355A
Authority
CN
China
Prior art keywords
cov
sars
mutant
nucleic acid
protein
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202210874769.0A
Other languages
Chinese (zh)
Inventor
赵干
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Advaccine Suzhou Biopharmaceutical Co ltd
Original Assignee
Advaccine Suzhou Biopharmaceutical Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Advaccine Suzhou Biopharmaceutical Co ltd filed Critical Advaccine Suzhou Biopharmaceutical Co ltd
Priority to CN202210874769.0A priority Critical patent/CN117448355A/en
Publication of CN117448355A publication Critical patent/CN117448355A/en
Pending legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K14/00Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof
    • C07K14/005Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof from viruses
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K39/00Medicinal preparations containing antigens or antibodies
    • A61K39/12Viral antigens
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61PSPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P31/00Antiinfectives, i.e. antibiotics, antiseptics, chemotherapeutics
    • A61P31/12Antivirals
    • A61P31/14Antivirals for RNA viruses
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N15/00Mutation or genetic engineering; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification; Use of hosts therefor
    • C12N15/09Recombinant DNA-technology
    • C12N15/63Introduction of foreign genetic material using vectors; Vectors; Use of hosts therefor; Regulation of expression
    • C12N15/79Vectors or expression systems specially adapted for eukaryotic hosts
    • C12N15/85Vectors or expression systems specially adapted for eukaryotic hosts for animal cells
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N5/00Undifferentiated human, animal or plant cells, e.g. cell lines; Tissues; Cultivation or maintenance thereof; Culture media therefor
    • C12N5/06Animal cells or tissues; Human cells or tissues
    • C12N5/0602Vertebrate cells
    • C12N5/0652Cells of skeletal and connective tissues; Mesenchyme
    • C12N5/0656Adult fibroblasts
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N5/00Undifferentiated human, animal or plant cells, e.g. cell lines; Tissues; Cultivation or maintenance thereof; Culture media therefor
    • C12N5/06Animal cells or tissues; Human cells or tissues
    • C12N5/0602Vertebrate cells
    • C12N5/0681Cells of the genital tract; Non-germinal cells from gonads
    • C12N5/0682Cells of the female genital tract, e.g. endometrium; Non-germinal cells from ovaries, e.g. ovarian follicle cells
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N5/00Undifferentiated human, animal or plant cells, e.g. cell lines; Tissues; Cultivation or maintenance thereof; Culture media therefor
    • C12N5/06Animal cells or tissues; Human cells or tissues
    • C12N5/0602Vertebrate cells
    • C12N5/0684Cells of the urinary tract or kidneys
    • C12N5/0686Kidney cells
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K39/00Medicinal preparations containing antigens or antibodies
    • A61K2039/51Medicinal preparations containing antigens or antibodies comprising whole cells, viruses or DNA/RNA
    • A61K2039/53DNA (RNA) vaccination
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K2317/00Immunoglobulins specific features
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07KPEPTIDES
    • C07K2319/00Fusion polypeptide
    • C07K2319/01Fusion polypeptide containing a localisation/targetting motif
    • C07K2319/02Fusion polypeptide containing a localisation/targetting motif containing a signal sequence
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N2510/00Genetically modified cells
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N2770/00MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA ssRNA viruses positive-sense
    • C12N2770/00011Details
    • C12N2770/20011Coronaviridae
    • C12N2770/20022New viral proteins or individual genes, new structural or functional aspects of known viral proteins or genes
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N2770/00MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA ssRNA viruses positive-sense
    • C12N2770/00011Details
    • C12N2770/20011Coronaviridae
    • C12N2770/20033Use of viral protein as therapeutic agent other than vaccine, e.g. apoptosis inducing or anti-inflammatory
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N2770/00MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA ssRNA viruses positive-sense
    • C12N2770/00011Details
    • C12N2770/20011Coronaviridae
    • C12N2770/20034Use of virus or viral component as vaccine, e.g. live-attenuated or inactivated virus, VLP, viral protein
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N2800/00Nucleic acids vectors
    • C12N2800/10Plasmid DNA
    • C12N2800/106Plasmid DNA for vertebrates
    • C12N2800/107Plasmid DNA for vertebrates for mammalian

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Genetics & Genomics (AREA)
  • Organic Chemistry (AREA)
  • Biomedical Technology (AREA)
  • Wood Science & Technology (AREA)
  • Biotechnology (AREA)
  • Zoology (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • General Health & Medical Sciences (AREA)
  • Biochemistry (AREA)
  • Microbiology (AREA)
  • General Engineering & Computer Science (AREA)
  • Virology (AREA)
  • Molecular Biology (AREA)
  • Medicinal Chemistry (AREA)
  • Cell Biology (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Animal Behavior & Ethology (AREA)
  • Veterinary Medicine (AREA)
  • Public Health (AREA)
  • Urology & Nephrology (AREA)
  • Biophysics (AREA)
  • Reproductive Health (AREA)
  • Gastroenterology & Hepatology (AREA)
  • Proteomics, Peptides & Aminoacids (AREA)
  • Mycology (AREA)
  • Medicines Containing Antibodies Or Antigens For Use As Internal Diagnostic Agents (AREA)
  • Plant Pathology (AREA)
  • Immunology (AREA)
  • Rheumatology (AREA)
  • Epidemiology (AREA)
  • Communicable Diseases (AREA)
  • Oncology (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Micro-Organisms Or Cultivation Processes Thereof (AREA)

Abstract

The invention relates to the field of biotechnology, in particular to a recombinant DNA molecule for encoding coronavirus antigen, a DNA vaccine and application thereof. The invention recombines nucleic acid molecule encoding SARS-CoV S protein RBD region and nucleic acid molecule encoding new SARS-CoV-2Omicron mutant S protein RBD region, the polypeptide encoded by the recombinant nucleic acid molecule has dual immunogenicity of SARS-CoV S protein RBD region and new SARS-CoV-2Omicron mutant S protein RBD region, when the polypeptide with dual immunogenicity is used as vaccine immune effect component, the induced neutralizing antibody can form immune reaction against SARS-CoV S protein RBD region and new SARS-CoV-2Omicron mutant S protein RBD region at the same time, and can induce specific humoral immunity and cell immune response.

Description

Recombinant DNA molecule for encoding coronavirus antigen, DNA vaccine and application
Technical Field
The invention relates to the field of biotechnology, in particular to a DNA molecule for encoding coronavirus antigen, a DNA vaccine and application thereof.
Background
Coronaviruses belong to the family Coronaviridae (Coronaviridae), including four genera of alpha-coronavirus, beta-coronavirus, gamma-coronavirus and delta-coronavirus, the novel coronavirus currently prevalent (Severe acute respiratory syndrome coronavirus, SARS-CoV-2) belongs to the coronavirus of the beta genus, and is mainly transmitted through respiratory droplets, and pneumonia (Novel Coronavirus-infected Pneumonia, NCP) can also be caused by contact transmission, so that the population is generally susceptible.
Currently, the world health organization is classified into two main categories in the classification of new coronavirus mutants, one category being a worrying mutant strain (VOC) and the other category being a mutant strain (VOI) of interest. Up to now there are 5 VOC mutants, alpha (Alpha, accession number b.1.1.7), beta (Beta, accession number b.1.351), gamma (Gamma, accession number p.1), delta (Delta, accession number b.1.617.2) and omicker (Omicron, accession number b.1.1.529) variants, respectively; the 8 VOI mutants were, respectively, epothilone (ep silon, accession No. b.1.427/429), zeta (Zeta, accession No. p.2), sita (Theta, accession No. P.3), eta (Eta, accession No. b.1.525), about tower (Iota, accession No. b.1.526), kappa (Kappa, accession No. b.1.617.1), lambda (Lambda, accession No. c.37), and muu (Mu, accession No. b.1.621). In particular, recent outbreaks of the omucon variant have 15 mutation sites in the Receptor Binding Domain (RBD) due to more than 30 mutations in the Spike segment of the major protective antigen, 11 of which are in the Receptor Binding Motif (RBM) region, including three mutations that were previously present in beta and gamma mutants: 417 484, and 501, wherein N501Y is also present in the alpha mutant. Most of the RBD antibodies bind to RBM regions, and when the RBM regions are mutated, the antibodies bound to these regions are easily affected and escape. It is worth mentioning that another 4 mutation sites not in the RBM region are distributed at the interaction interface of S monomers, which may affect the stability of trimer. In addition, of the 15 mutations, 9 sites were not conserved between SARS-CoV-2S and SARS-CoV S, and the mutation occurred in the non-conserved region. While the mutation sites of the amino-terminal domain (NTD) are concentrated around: A67V/Del69-70; T95I; G142D/Del143-145; del211/L212I, which is structurally concentrated on the NTD surface and is also a common recognition site for novel crown NTD antibodies; thus, simultaneous mutation of these sites also affects the affinity and neutralizing activity of the NTD antibodies. Based on the existing knowledge of mutation sites, the variant breaks through the protection of most of neutralizing antibodies, and part of previous data shows that the variant reduces the neutralizing antibodies of the novel crown vaccine by about 40 times compared with the wild type, and based on various frequent variants and the appearance of super transmissible Omikovia, the development of a broad-spectrum vaccine which is 'in a non-allergic manner' is an effective means for coping with the frequent variants.
In view of this, the present invention has been made.
Disclosure of Invention
It is an object of the present invention to provide a recombinant nucleic acid molecule encoding SARS-CoV and SARS-CoV-2 viral antigens, which is expected to achieve a broad-spectrum immune effect "in the absence of strain".
It is a second object of the present invention to provide a biological material comprising the recombinant nucleic acid molecule described above.
It is a further object of the present invention to provide the use of the above biological material.
It is a fourth object of the present invention to provide a DNA vaccine of SARS-CoV and/or SARS-CoV-2 virus comprising the above recombinant nucleic acid molecule and/or biological material.
The fifth object of the present invention is to provide a method for producing the DNA vaccine.
In order to solve the technical problems and achieve the purposes, the invention provides the following technical scheme:
in a first aspect, the present invention provides a recombinant nucleic acid molecule comprising any one of (a) to (c) as follows:
(a) The recombinant DNA molecules comprise a first DNA molecule encoding the RBD region of SARS-CoV S protein and a second DNA molecule encoding the RBD region of S protein of the novel SARS-CoV-2 Omicron mutant strain;
(b) A DNA molecule derived from (a) by substitution, deletion or addition of one or several nucleotides in the nucleotide sequence of the recombinant DNA molecule defined in (a) and having the function of encoding the RBD region of SARS-CoV S protein and encoding the RBD region of S protein of the novel SARS-CoV-2 Omicron mutant;
(c) Nucleic acid molecules which hybridize under stringent conditions with the nucleotide sequence of the recombinant DNA molecule defined in (a) or the DNA molecule defined in (b) and which encode the RBD region of the SARS-CoV S protein and the RBD region of the S protein of the novel SARS-CoV-2 Omicron mutant strain.
In an alternative embodiment, the amino acid sequence encoded by the first DNA molecule is shown in SEQ ID No. 1; the amino acid sequence of the second DNA molecule is shown as SEQ ID No. 2.
In an alternative embodiment, the nucleotide sequence of the first nucleic acid molecule is set forth in SEQ ID No. 3; the nucleotide sequence of the second nucleic acid molecule is shown as SEQ ID No. 4.
Preferably, the nucleotide sequence of the recombinant nucleic acid molecule is shown as SEQ ID No.5, or has at least 90% identity with the nucleotide sequence shown as SEQ ID No.5, and encodes the RBD region of SARS-CoV S protein and the RBD region of novel SARS-CoV-2 Omicron mutant S protein.
In a second aspect, the present invention provides a biomaterial comprising:
a construct comprising a recombinant nucleic acid molecule according to any one of the preceding embodiments; and, a third nucleic acid molecule encoding a signal peptide linked to the 5' end of the recombinant nucleic acid molecule;
(ii) recombinant expression vectors, including original expression vectors; and, inserting into the original expression vector a coding nucleic acid fragment selected from the recombinant nucleic acid molecule of any one of the preceding embodiments or the (i) construct; preferably, the original expression vector is a pVAX1 plasmid;
(iii) a transformant obtained by introducing the recombinant expression vector of (ii) into a host cell selected from the group consisting of insect cells, yeast, avian cells, and mammalian cells; preferably, the host cell is HEK293, CHO or COS-7;
(iv) a polypeptide comprising a polypeptide encoded by the recombinant nucleic acid molecule of any one of the preceding embodiments, a polypeptide encoded by the construct of (i), or a polypeptide obtained by expression of a transformant of (iii);
(V) an antibody that specifically binds to the (IV) polypeptide.
In an alternative embodiment, the signal peptide encoded by the third nucleic acid molecule comprises the following (c) or (d):
(c) A signal peptide with an amino acid sequence shown as SEQ ID No. 6;
(d) A signal peptide derived from (c) having a signal peptide function by substituting, deleting or adding one or more amino acids in the amino acid sequence of the signal peptide defined in (c).
In a third aspect, the invention provides the use of a recombinant nucleic acid molecule according to any one of the preceding embodiments or a biological material according to any one of the preceding embodiments in (a) or (B) as follows:
(A) Preparing vaccine for preventing and/or treating SARS-CoV and/or SARS-CoV-2 virus infection;
(B) Preparing medicine for preventing and/or treating SARS-CoV and/or SARS-CoV-2 virus-induced related diseases.
In alternative embodiments, the SARS-CoV-2 virus comprises a wild-type strain, a B.1.617.2 mutant, a B.1.1.7 mutant, a B.1.351 mutant, a P.1 mutant, a B.1.2 mutant, a B.1 mutant, a B.1.621 mutant, a B.1.525 mutant, a B.1.526 mutant, a C.37 mutant, a B.1.617.1 mutant or a B.1.1.529 mutant.
In a fourth aspect, the invention provides a DNA vaccine comprising the recombinant nucleic acid molecule of any one of the preceding embodiments or the recombinant expression vector of any one of the preceding embodiments.
In alternative embodiments, the DNA vaccine further comprises at least one of a pharmaceutically acceptable adjuvant, carrier, diluent, or excipient;
and/or at least one drug having a therapeutic effect on SARS-CoV and/or SARS-CoV-2 virus;
preferably, the adjuvant comprises at least one of an aluminium adjuvant, TLRs ligand, metal ion, cytokine or chemokine adjuvant;
further preferably, the metal ion comprises Mn 2+ And/or Zn 2+
In an alternative embodiment, the recombinant nucleic acid molecule of any one of the preceding embodiments or the recombinant expression vector of any one of the preceding embodiments is introduced into a host cell and cultured, and the recombinant nucleic acid molecule or the recombinant expression vector in the host cell is extracted to obtain a DNA vaccine.
In a fifth aspect, the present invention provides the use of a DNA vaccine according to the preceding embodiments in (i) to (iv) as follows:
(i) Regulating immunity of organism;
(ii) anti-SARS-CoV-2 virus infection;
(iii) anti-SARS-CoV virus infection;
(iv) Prevent immunopathogenic injury.
Preferably, the SARS-CoV-2 virus comprises a wild-type strain, a B.1.617.2 mutant, a B.1.1.7 mutant, a B.1.351 mutant, a P.1 mutant, a B.1.2 mutant, a B.1 mutant, a B.1.621 mutant, a B.1.525 mutant, a B.1.526 mutant, a C.37 mutant, a B.1.617.1 mutant or a B.1.1.529 mutant.
In a sixth aspect, the present invention provides a method for preventing and/or treating infection of a mammal with SARS-CoV and/or SARS-CoV-2 virus, said method comprising vaccinating said mammal with a DNA vaccine as described above.
Preferably, the SARS-CoV-2 virus comprises a wild-type strain, a B.1.617.2 mutant, a B.1.1.7 mutant, a B.1.351 mutant, a P.1 mutant, a B.1.2 mutant, a B.1 mutant, a B.1.621 mutant, a B.1.525 mutant, a B.1.526 mutant, a C.37 mutant, a B.1.617.1 mutant or a B.1.1.529 mutant.
Preferably, the mammal is a human.
The invention recombines the nucleic acid molecule encoding the RBD region of SARS-CoV S protein with the nucleic acid molecule encoding the RBD region of S protein of new SARS-CoV-2 Omicron mutant, the polypeptide encoded by the recombinant nucleic acid molecule has the double immunogenicity of the RBD region of SARS-CoV S protein and the RBD region of S protein of new SARS-CoV-2 Omicron mutant, when the polypeptide with double immunogenicity is used as the vaccine immune effect component, the synthesized neutralizing antibody can form immune reaction against the RBD region of S protein of SARS-CoV and the RBD region of S protein of new SARS-CoV-2 Omicron mutant. Meanwhile, by adopting the SARS-CoV and SARS-CoV-2 double antigen design with far relative relationship, the conservative epitope aiming at the beta-coronavirus is amplified as much as possible, thereby avoiding the antigen drift caused by continuous mutation in the relative of SARS-CoV-2, and realizing the broad-spectrum immune effect of' in non-allergic ten thousand. Meanwhile, compared with the serial sequence of the Omicron-SARS RBD, the serial sequence of the SARS-Omicron RBD selected on the protein domain serial strategy enables the two antigen domains of the SARS RBD and the Omicron RBD to be far away from each other, the corresponding domains can be fully exposed, and the more the exposure degree of the antigen domains is, the more complete the corresponding antibody response spectrum is excited, and the better the immune effect is.
Based on the beneficial effects of the recombinant nucleic acid molecules, the invention also provides a preparation method of the recombinant nucleic acid molecules, biological materials used for preparing the recombinant nucleic acid molecules, and polypeptides obtained by expressing the recombinant nucleic acid molecules, and also provides a DNA vaccine taking the biological materials as main immune components and a preparation method of the DNA vaccine, which is verified to be capable of effectively transcribing and expressing in mammalian cells, and also has good immunogenicity, can obviously excite experimental animals to generate antigen-specific antibodies for humoral immune responses, can generate antibodies against new crown Delta mutant antigens, beta mutant antigens, omicron mutant antigens and antibodies of SARS-CoV antigens, and has good neutralizing activity; for cellular immune responses, the DNA vaccine was able to induce the production of higher levels of antigen-specific CD4 ifnγ and CD4 TNF- α T cell subsets against the new crown wild type antigen as well as the Omicron mutant antigen; meanwhile, the DNA vaccine can effectively prevent or inhibit the replication of the novel crown Omicron mutant virus in vivo, and has a good vaccine protection effect. The experiments show that the DNA vaccine has good immunogenicity and broad spectrum.
Based on this, the DNA vaccine provided by the present invention can regulate the immune function of organism, effectively prevent SARS-CoV and/or SARS-CoV-2 virus and its mutant strain infection, and also can intervene in the treatment of diseases caused by SARS-CoV and/or SARS-CoV-2 virus and its mutant strain.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.
FIG. 1 is a graph showing the result of scoring the codon optimization index of the DNA sequence provided in example 1 of the present invention;
FIG. 2 is a graph showing GC content scoring results after DNA sequence optimization provided in example 1 of the present invention;
FIG. 3 is a graph showing the result of scoring the number of negative regulatory elements after optimizing the DNA sequence provided in example 1 of the present invention;
FIG. 4 is a graph showing the result of qPCR expression fold after optimizing the DNA sequence provided in example 1 of the present invention;
FIG. 5 is a structural analysis of the binding protein according to example 1 of the present invention;
FIG. 6 shows qPCR expression results of a novel coronavirus broad-spectrum candidate DNA vaccine provided in example 3 of the present invention;
FIG. 7 shows the results of antigen-specific antibodies on day 14 after primary immunization of a novel coronavirus broad-spectrum candidate DNA vaccine provided in example 4 of the present invention;
FIG. 8 shows the results of antigen-specific antibodies on day 14 after booster immunization with the novel coronavirus broad-spectrum candidate DNA vaccine provided in example 4 of the present invention;
FIG. 9 shows the result of neutralizing antibodies on day 14 after booster immunization with a broad-spectrum candidate DNA vaccine for coronaviruses according to example 4 of the present invention;
FIG. 10 is a comparison of neutralizing antibodies at day 14 after booster immunization for each vaccine provided in example 4 of the present invention;
FIG. 11 shows the results of antigen-specific CD4 IFN-gamma T cell subsets on day 14 after booster immunization with the novel coronal wild strain, coronavirus broad-spectrum candidate DNA vaccine provided in example 4 of the present invention;
FIG. 12 shows the results of antigen-specific CD4 TNF-. Alpha.T cell subset on day 14 after booster immunization with the novel coronal wild strain, coronavirus broad-spectrum candidate DNA vaccine provided in example 4 of the present invention;
FIG. 13 shows the results of antigen-specific antibodies on day 17 after booster immunization with a broad-spectrum candidate DNA vaccine of coronavirus provided in example 5 of the present invention;
FIG. 14 shows the result of neutralizing antibodies against novel coronavirus Omacron BA.1 type mutant strain virus on day 17 after booster immunization with coronavirus broad-spectrum candidate DNA vaccine provided in example 5 of the present invention;
FIG. 15 is a graph showing the result of neutralizing antibodies against a novel coronavirus Omacron BA.2 type mutant strain virus on day 17 after booster immunization with a coronavirus broad-spectrum candidate DNA vaccine according to example 5 of the present invention;
FIG. 16 shows the results of lung gRNA detection of mice challenged with the novel crown Omicron BA.1 type mutant virus provided in example 5 of the present invention;
FIG. 17 shows the results of lung sgRNA detection after challenge of mice with the novel crown Omicron BA.1 type mutant virus provided in example 5 of the present invention.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. Generally, the nomenclature used in connection with the cell and tissue culture, molecular biology, immunology, microbiology, genetics, and protein and nucleic acid chemistry and hybridization described herein and the techniques thereof are those well known and commonly employed in the art. Unless otherwise indicated, the methods and techniques of the present invention are generally well known in the art and are performed according to conventional methods as described in various general and more specific references cited and discussed throughout the present specification. Enzymatic reactions and purification techniques are performed according to manufacturer's instructions, as commonly accomplished in the art, or as described herein. Nomenclature used in connection with the analytical chemistry, synthetic organic chemistry, and medical and pharmaceutical chemistry described herein, and the laboratory procedures and techniques therefor, are those well known and commonly employed in the art.
Thus, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures. Furthermore, the terms "first," "second," "third," and the like are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.
In a first embodiment, the present invention provides a recombinant nucleic acid molecule comprising any one of the following (a) to (c):
(a) The recombinant DNA molecules comprise a first DNA molecule encoding the RBD region of SARS-CoV S protein and a second DNA molecule encoding the RBD region of S protein of the novel SARS-CoV-2 Omicron mutant strain;
(b) A DNA molecule derived from (a) by substitution, deletion or addition of one or several nucleotides in the nucleotide sequence of the recombinant DNA molecule defined in (a) and having the function of encoding the RBD region of SARS-CoV S protein and encoding the RBD region of S protein of the novel SARS-CoV-2 Omicron mutant;
(c) Nucleic acid molecules which hybridize under stringent conditions with the nucleotide sequence of the recombinant DNA molecule defined in (a) or the DNA molecule defined in (b) and which encode the RBD region of the SARS-CoV S protein and the RBD region of the S protein of the novel SARS-CoV-2 Omicron mutant strain.
It should be noted that the present invention is not limited to the above-described sequence of the first DNA molecule and the second DNA molecule, and in some embodiments the recombinant nucleic acid molecule comprises the first DNA molecule and the second DNA molecule sequentially connected from the 5 'end to the 3' end, and in other embodiments the recombinant nucleic acid molecule obtained by exchanging the sequence of the first DNA molecule and the second DNA molecule may still have a broad spectrum of immunogenicity. Those skilled in the art can choose the connection sequence of the first DNA molecule and the second DNA molecule according to specific experimental conditions and actual requirements, and the connection manner given in the embodiment of the present invention is only an example, and is not limited to the connection sequence.
It will be understood that the above-mentioned recombinant nucleic acid molecule (c) hybridizes with the recombinant DNA molecule (a) or the DNA molecule (b) under "stringent conditions" means a recombinant nucleic acid molecule (c) obtained by hybridization using the recombinant DNA molecule (a) or the DNA molecule (b) as a template in accordance with the base complementary pairing rules. Also, it will be appreciated by those skilled in the art that the recombinant nucleic acid molecule (c) includes both the DNA molecules obtained by replication and the various RNA molecules obtained by transcription.
In addition, the nucleotide sequence provided by the invention is obtained by optimizing an unique codon optimization system.
In an alternative embodiment, the amino acid sequence encoded by the first DNA molecule is shown in SEQ ID No. 1; the amino acid sequence of the second DNA molecule is shown as SEQ ID No. 2.
It should be noted that, in the polypeptide space conformation folding process, the SARS-CoV S protein RBD region fragment and the new SARS-CoV-2 Omicron mutant S protein RBD region fragment have mutual influence, and the serial sequence of the SARS-Omicron RBD is compared with the serial sequence of the Omicron-SARS RBD so that the two antigen domains of the SARS RBD and the Omicron RBD are far away from each other, the corresponding domains can be fully exposed, and the more sufficient the exposure degree of the antigen domains, the more complete the corresponding antibody response spectrum is stimulated, and the better the immune effect is. The SEQ ID No.1 and the SEQ ID No.2 are optimal combined sequences which have complete functions and small mutual interference of the RBD region of the selected SARS-CoV S protein and the RBD region of the novel SARS-CoV-2 Omicron mutant S protein, aiming at realizing the wide-spectrum long-acting immunogenicity of 'non-allergic ten-thousand'. From the foregoing, it will be appreciated that there are a variety of other derived polypeptides that can be used in the invention in which the SARS-CoV S protein RBD region encoded by the first DNA molecule of the invention, e.g., the 5 'and/or 3' ends of SEQ ID No.1, have been deleted or added with one or more amino acids. Similarly, the novel SARS-CoV-2 Omicron mutant S protein RBD region encoded by the second DNA molecule of the present invention also comprises derivative polypeptide obtained by deleting or adding one or more amino acids at the 5 'end and/or 3' end of SEQ ID No. 1.
In an alternative embodiment, the nucleotide sequence of the first nucleic acid molecule is set forth in SEQ ID No. 3; the nucleotide sequence of the second nucleic acid molecule is shown as SEQ ID No. 4.
Preferably, the nucleotide sequence of the recombinant nucleic acid molecule is shown as SEQ ID No.5, or has at least 90% identity with the nucleotide sequence shown as SEQ ID No.5, and encodes the RBD region of SARS-CoV S protein and the RBD region of novel SARS-CoV-2 Omicron mutant S protein.
It is understood that in the present invention, "identity" refers to similarity between nucleotide sequences, including nucleotide sequences having at least 90% (e.g., may be, but not limited to, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or more) identity to the nucleotide sequence set forth in SEQ ID No.5 of the present invention.
In a second aspect, the present invention provides a biomaterial comprising:
a construct comprising a recombinant nucleic acid molecule according to any one of the preceding embodiments; and, a third nucleic acid molecule encoding a signal peptide linked to the 5' end of the recombinant nucleic acid molecule;
(ii) recombinant expression vectors, including original expression vectors; and, inserting into the original expression vector a coding nucleic acid fragment selected from the recombinant nucleic acid molecule of any one of the preceding embodiments or the (i) construct; preferably, the original expression vector is a pVAX1 plasmid;
(iii) a transformant obtained by introducing the recombinant expression vector of (ii) into a host cell selected from the group consisting of insect cells, yeast, avian cells, and mammalian cells; preferably, the host cell is HEK293, CHO or COS-7;
(iv) a polypeptide comprising a polypeptide encoded by the recombinant nucleic acid molecule of any one of the preceding embodiments, a polypeptide encoded by the construct of (i), or a polypeptide obtained by expression of a transformant of (iii);
(V) antibodies, such as monoclonal or polyclonal antibodies, that specifically bind to the (IV) polypeptide.
It should be noted that the original expression vector may be a eukaryotic expression vector, and the protein encoded by the DNA molecule is produced by cellular transcription and translation mechanisms. Alternatively, the original expression vector may have expression signals such as a strong promoter, a strong stop codon, regulation of the distance between the promoter and the cloned gene, and transcription termination sequence insertion. Preferably, the eukaryotic expression vector includes pVAX1, but is not limited to any other expression vector capable of expressing DNA and enabling cells to translate sequences into antigens recognized by the immune system.
For the above-mentioned host cells, which are only typical preferred cells according to the present invention, those skilled in the art can select other suitable host cells according to the actual experimental conditions or actual requirements, and are not limited to eukaryotic cells or prokaryotic cells.
It can be appreciated that the biomaterial provided by the invention can be directly applied to production of different requirements and scenes as a biological module.
In an alternative embodiment, the signal peptide encoded by the third nucleic acid molecule comprises the following (c) or (d):
(c) A signal peptide with an amino acid sequence shown as SEQ ID No. 6;
(d) A signal peptide derived from (c) having a signal peptide function by substituting, deleting or adding one or more amino acids in the amino acid sequence of the signal peptide defined in (c).
The signal peptide is matched with the efficient expression of SARS-CoV and SARS-CoV-2 virus genes, and can raise the expression efficiency of the recombinant nucleic acid molecule in host obviously.
In a third aspect, the invention provides the use of a recombinant nucleic acid molecule according to any one of the preceding embodiments or a biological material according to any one of the preceding embodiments in (a) or (B) as follows:
(A) Preparing vaccine for preventing and/or treating SARS-CoV and/or SARS-CoV-2 virus infection;
(B) Preparing medicine for preventing and/or treating SARS-CoV and/or SARS-CoV-2 virus related diseases, including lung injury, brain injury, liver and kidney injury or heart injury.
In alternative embodiments, the SARS-CoV-2 virus comprises a wild-type strain, a B.1.617.2 mutant, a B.1.1.7 mutant, a B.1.351 mutant, a P.1 mutant, a B.1.2 mutant, a B.1 mutant, a B.1.621 mutant, a B.1.525 mutant, a B.1.526 mutant, a C.37 mutant, a B.1.617.1 mutant or a B.1.1.529 mutant.
In a fourth aspect, the invention provides a DNA vaccine comprising the recombinant nucleic acid molecule of any one of the preceding embodiments or the recombinant expression vector of any one of the preceding embodiments.
The DNA vaccine not only can be effectively transcribed and expressed in mammalian cells, but also has good immunogenicity, and can obviously excite experimental animals to generate antigen-specific antibodies for humoral immune response, so that the DNA vaccine not only can generate antibodies aiming at novel crown wild type antigens, but also can generate antibodies aiming at novel crown Delta mutant strain antigens, beta mutant strain antigens, omicron mutant strain antigens and SARS-CoV antigens, and has good neutralizing activity; for cellular immune responses, the DNA vaccine was able to induce the production of higher levels of antigen-specific CD4 ifnγ and CD4 TNF- α T cell subsets against the new crown wild type antigen as well as the Omicron mutant antigen; meanwhile, the DNA vaccine can effectively prevent or inhibit the replication of the novel crown Omicron mutant virus in vivo, and has a good vaccine protection effect. The experiments show that the DNA vaccine has good immunogenicity and broad spectrum.
In some embodiments, the DNA vaccine further comprises at least one of a pharmaceutically acceptable adjuvant, carrier, diluent, or excipient to increase the ability of its active ingredient DNA molecule to generate an immune response in a subject. The adjuvant comprises at least one of aluminum adjuvant, TLRs ligand, metal ion, cytokine or chemokine adjuvant; preferably, the metal ions include Mn 2+ And/or Zn 2+
In other embodiments, the DNA vaccine further comprises at least one agent that has a therapeutic effect on SARS-CoV and/or SARS-CoV-2 virus to enhance the therapeutic effect of the vaccine on SARS-COV and/or SARS-COV-2 virus-induced disease.
In still other embodiments, the DNA vaccine comprises at least one of the pharmaceutically acceptable adjuvants, carriers, diluents or excipients described above and at least one agent having therapeutic effect on SARS-CoV and/or SARS-CoV-2 virus.
In an alternative embodiment, a recombinant nucleic acid molecule according to any one of the preceding embodiments or a recombinant expression vector according to any one of the preceding embodiments is introduced into a host cell and cultured, and the recombinant nucleic acid molecule or recombinant expression vector in the host cell is extracted to prepare a DNA vaccine.
In a fifth aspect, the present invention provides a method for preventing and/or treating infection of a mammal with SARS-CoV and/or SARS-CoV-2 virus, said method comprising vaccinating said mammal with a DNA vaccine as described above.
In alternative embodiments, the SARS-CoV-2 virus comprises a wild-type strain, a B.1.617.2 mutant, a B.1.1.7 mutant, a B.1.351 mutant, a P.1 mutant, a B.1.2 mutant, a B.1 mutant, a B.1.621 mutant, a B.1.525 mutant, a B.1.526 mutant, a C.37 mutant, a B.1.617.1 mutant or a B.1.1.529 mutant.
In an alternative embodiment, the mammal is a human.
The DNA vaccine provided by the invention has the following action mechanism: the optimized nucleotide sequence of the RBD region of the SARS-CoV S protein is connected in series with the optimized nucleotide sequence of the RBD region of the S protein of the mutant strain S protein of the new SARS-CoV-2 Omicron, and the eukaryotic expression vector is inserted after the high-efficiency expression signal peptide is added, so that the eukaryotic expression vector is introduced into host cells to enable the eukaryotic expression vector to efficiently express virus antigens in the host cells, and antiviral humoral immune response and cellular immune response are systematically activated through an antigen presenting process. Antibodies raised by the activated humoral immune response may prevent viral entry, and the activated cellular immune response may further clear virus-infected cells and modulate adverse reactions due to potential side effects of ADE.
Based on the action mechanism, the invention also provides application of the DNA vaccine, which comprises the following steps:
(i) Regulating immunity of organism;
(ii) anti-SARS-COV-2 virus infection;
(iii) anti-SARS-COV virus infection;
(iv) Prevent immunopathogenic injury.
Some embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following embodiments and features of the embodiments may be combined with each other without conflict.
Example 1: optimized screening of nucleic acid encoding S protein RBD region protein
In order to increase the protein expression of a target protein in a host cell, the nucleic acid sequence of the target gene needs to be optimized, and the general principle of nucleic acid sequence optimization is as follows: (1) Optimizing degenerate codons according to the preference of the host cell for nucleic acid codons, so that the optimized sequence contains more nucleic acid codons which are favorable for the host cell to recognize; (2) Further optimizing the GC content in the nucleic acid sequence on the basis of codon preference optimization, so that the sequence with optimized GC content can express more target proteins; (3) Optimizing the nucleic acid sequence to enable the nucleic acid sequence to transcribe more stable mRNA, and facilitating translation of target protein; (4) Changing the codon frequency of host preference, and increasing CAI index (codon adaptation index). The GC content in the nucleotide sequence is regulated by optimizing the nucleotide sequence of the RBD region of the SARS-CoV S protein and the nucleotide sequence of the RBD region of the S protein of the novel SARS-CoV-2 Omicron mutant strain; simultaneously, the codon frequency of host preference is changed, and the CAI (codon adaptation index) index is improved; the free energy of the formed RNA secondary structure is reduced, the proportion of the Negative CIS element is reduced, the proportion of the repeated sequence in the sequence is reduced, in addition, the optimization of the signal peptide is carried out, and the specific algorithm of the company formed by the experiences of the inventor in the field for years is combined, so that the expression quantity of the RNA can be further improved, the optimized nucleotide sequence is obtained, and the RNA vaccine is prepared.
The optimization process comprises the following steps: the nucleotide sequence (AY 278488, genBank) of the wild SARS-CoV S protein RBD region before optimization is selected to obtain the nucleotide sequence shown as SEQ ID No.3 according to the optimization strategy of the invention, the nucleotide sequence (EPI_ISL_6640917, GISAID) of the wild SARS-CoV-2 Omicron mutant S protein RBD region before optimization is selected to obtain the nucleotide sequence shown as SEQ ID No.4 according to the optimization strategy of the invention, the nucleotide sequence of the coding signal peptide shown as SEQ ID No.7 is added at the front end N end of SEQ ID No.3 and the TGATAA stop codon is added at the end C end of SEQ ID No.4 after direct series connection is carried out, the nucleotide sequence shown as SEQ ID No.5 is finally obtained, and the nucleotide sequence shown as SEQ ID No.9 is finally obtained by adopting the conventional commercial database (Integrated DNA Technologies, IDT) optimization strategy. Scoring the nucleotide sequence of SEQ ID No.5 before optimization and SEQ ID No.9 after optimization and obtained by conventional commercial optimization in the invention; in terms of optimizing and increasing expression of DNA sequences, key indexes of optimizing effect and DNA optimization are as follows: codon optimisation is indexed positively, GC content positively, negatively with the number of negative regulatory elements. As shown in fig. 1-3, the optimization strategy adopted by the invention is found to have a remarkable improvement on key indexes compared with the conventional commercial optimization strategy, and can be predicted to increase the expression efficiency of the optimized genes.
The wild sequence before the optimization, SEQ ID No.5 after the optimization of the invention and 3 nucleotide sequences of SEQ ID No.9 obtained from a conventional commercial database are respectively transformed and constructed into a pVAX1 vector (ThermoFisher, cat# V26020) to obtain 3 plasmid DNAs, namely pSARS-Omicron Dimer-wild, pSARS-Omicron Dimer and pSARS-Omicron Dimer-conventional optimization. 3 plasmids are respectively transfected into HEK293T cells for 48 hours, RNA is extracted, and the transcription level of plasmid DNA obtained in different optimization modes is identified by adopting a qPCR method. As shown in FIG. 4, the optimized DNA sequence of the invention can be increased by more than 100 times compared with the wild sequence before the optimization in RNA transcription level, and can be increased by more than 2.5 times compared with the conventional optimized molecules in the commercial database in RNA transcription level, so that the optimized nucleic acid molecules of the invention are better than the conventional commercial database. The improvement of the transcription level of the DNA vaccine can improve the protein expression quantity, so that the immune effect of the DNA vaccine is improved, the sequence obtained by the design of the invention is obviously improved in the transcription level, and the protein expression quantity is obviously improved, so that the obvious and better immune effect is obtained.
When designing and optimizing nucleotide sequences, firstly, the serial design of nucleic acid sequences is considered by adopting the coronavirus of beta genus, including severe respiratory syndrome coronavirus (SARS-CoV), middle east respiratory syndrome coronavirus (MERS-CoV) and novel coronavirus (SARS-CoV-2), and the combined receptor when the MERS-CoV infects a host is CD26 (DPP 4), and the combined receptor of SARS-CoV and SARS-CoV-2 is ACE2, when the structural difference of the receptor is predicted from virology and immunology, the immune effect on the novel coronavirus is expected to be weaker, so that the RBD serial design of S proteins of the SARS-CoV and the SARS-CoV-2 is considered, and the serial strategy of different protein domains is considered to influence the exposure degree of antigen domains, and the more complete corresponding antibody response spectrum excited by the antigen domains is considered, and the immune effect is better. Therefore, the serial sequence of the SARS-CoV S protein RBD region (SARS RBD) and the new SARS-CoV-2 Omicron mutant strain S protein RBD region (Omicron RBD) is analyzed by biological informatics means such as artificial intelligent binding protein structure analysis; as shown in FIG. 5, the analysis results show that the tandem sequence of SARS-Omicron RBD (A diagram) makes the two antigen domains of SARS RBD and Omicron RBD far away from each other and the corresponding domains can be fully exposed compared with the tandem sequence of Omicron-SARS RBD (B diagram), thus also indicating that the tandem strategy of SARS-Omicron RBD has better immune effect in the invention.
Example 2: construction process of DNA vaccine
1. Preparation method of coronavirus broad-spectrum candidate DNA vaccine
1.1. Construction of plasmids
The nucleotide sequence (from AY278488, genBank) encoding the RBD region of SARS-CoV S protein is shown in SEQ ID No.3, and the nucleotide sequence (from EPI_ISL_6640917, GISAID) encoding the RBD region of S protein of the novel SARS-CoV-2 Omicron mutant strain is shown in SEQ ID No. 4. After SEQ ID No.3 and SEQ ID No.4 are directly connected in series, a nucleotide sequence of coding signal peptide shown as SEQ ID No.7 is added at the front end N end of SEQ ID No.3, and a TGATAA stop codon is added at the tail end C end of SEQ ID No.4, so that a nucleotide sequence shown as SEQ ID No.5 is finally obtained, and SEQ ID No.5 is inserted between BamHI and Xho I sites of the pVAX1 vector, so that a plasmid pSARS-Omicron Dimer is obtained.
The nucleotide sequence shown in SEQ ID No.8 was obtained by optimizing based on the wild-type sequence (MN 908947.3, NCBI) of the novel coronavirus SARS-CoV-2, and the nucleotide sequence shown in SEQ ID No.8 was inserted between BamHI and XhoI sites of the pVAX1 vector to obtain a novel coronavirus wild-type strain plasmid (pWT). The pWT wild strain vaccine is a product aiming at the wild strain in the early stage of the company, and currently enters phase III clinic, so that the vaccine has very excellent immune effect.
DNA vaccine sequence transformation
Mu.l of DH10B competent cell suspension was taken from a-80℃refrigerator and thawed on ice. Add plasmid DNA solution (volume no more than 10. Mu.l) and gently shake well and place on ice for 30min. The mixture was heat-shocked in a water bath at 42℃for 70 seconds and rapidly cooled on ice for 5min. 0.9ml of LB liquid medium (without antibiotics) is added into the tube, and after uniform mixing, the bacteria are cultured for 45min at 37 ℃ in a shaking way, so that the bacteria are recovered to a normal growth state. Shaking the bacterial liquid evenly, taking 100 mu L of the bacterial liquid, coating the bacterial liquid on a screening plate containing proper antibiotics, placing the bacterial liquid on the front surface upwards, inverting a culture dish after the bacterial liquid is completely absorbed by a culture medium, and culturing the bacterial liquid at 37 ℃ for 12-16h. The uniform shape of the monoclonal cells were selected, and the clones were pricked using a sterile pipette head and placed in 5mL of LB selection medium containing 50mg/mL kanamycin for overnight culture at 37 ℃.
DNA vaccine plasmid extraction
The bacterial liquid is added into 200-400 mL LB selection medium containing kanamycin (50 mg/mL mother liquor, 1:1000 is used) according to the ratio of 1:1000, and the bacterial liquid is cultured for 12-16h at 37 ℃ at 200 rpm. Plasmid extraction was performed with EndoFreen Plasmid Maxi kit (QIAGEN, germany): and (3) centrifuging the bacterial liquid cultured for 12-16h at the speed of 8000rpm at the temperature of 4 ℃ for 10min, collecting bacterial bodies by discarding the supernatant, adding 10ml of P1 Buffer to resuspension the bacterial liquid, adding 10ml of P2 Buffer, gently reversing for 4-6 times, uniformly mixing, and incubating at room temperature for 5min for full lysis. 10ml of P3 Buffer is added into the mixed solution, after 4-6 times of even mixing are gently reversed to terminate the cleavage, all the mixture is transferred into QIAfilter Cartridge, incubated for 10min at room temperature, and the embolic filtering supernatant is added. The filtrate was transferred to a clean endotoxin-free 50ml centrifuge tube, 2.5ml ER Buffer was added, gently inverted 10 times, mixed well and then placed on ice for incubation for 30min. QIAGEN-tip 500 was taken out, 10ml of QBT Buffer was added to the equilibrated column, the above liquid was transferred to the column, the plasmid was adsorbed by gravity flow, washed 2 times with 30ml of QC Buffer, and eluted with 15ml of QN Buffer. Each tube of sample was precipitated with 10.5ml of isopropanol and centrifuged at 4000g for 30min at 4 ℃. The supernatant was discarded, washed 1 time with 70% ethanol, and centrifuged at 4000g for 10min at 4 ℃. The supernatant was discarded, the pellet was dried, and 500. Mu.l of endotoxin-free water was added to each sample to resuspend the plasmid, thereby obtaining a recombinant expression plasmid for preparing DNA vaccine.
Example 3: mammalian cell transcriptional identification of coronavirus broad-spectrum candidate DNA vaccine
To verify whether the plasmid constructed in example 2 was able to be transcribed efficiently in mammalian cells, it was identified by methods of DNA transfection in vitro, RNA extraction, qPCR.
DNA vaccine in vitro transfection
Frozen HEK293T cell lines were removed from liquid nitrogen and centrifuged at 1000rpm for 5min after a 37 ℃ water bath to remove DMSO. Adding serum-free DMEM culture solution, washing once, adding into 5ml of DMEM culture solution containing 10% calf serum, 37deg.C and 5% CO 2 Culturing for 2-3 generations for standby. After digestion of cells with pancreatin (0.25% EDTA) at 37℃for 1min and termination with complete medium, the cells were incubated at 2-4X 10 6 Cell/well density was plated on 60mm dishes, 5ml of growth medium (without 1% diabody) was added at 37℃with 5% CO 2 Culturing in an incubator for 24 hours.
Mu.g of pSARS-Omicron Dimer and 4. Mu.g of pWT were added to 500. Mu.l of reduced serum OPTI-MEM medium, respectively, gently mixed, and simultaneously 24. Mu.l of cationic liposome (Shanghai Saint, 40802ES 03) was gently mixed in 500. Mu.l of reduced serum OPTI-MEM medium, and left at room temperature for 5min, and the above two plasmids were mixed with liposome 1:1, respectively, and left at room temperature for 20min, to give a plasmid DNA/liposome complex.
The plasmid DNA/liposome complex was added to the 60mm dish for 24 hours at 37℃in 1 ml/dish, 5% CO 2 The incubators were incubated to 48 hours each for subsequent experiments.
2. Post-transfection RNA extraction
The cells transfected to 48 hours above were collected by digestion, resuspended in 1ml of complete medium, 100. Mu.l were aspirated for RNA extraction, and the remaining resuspension was used for subsequent WB sample preparation.
100 μl of the aspirated cell suspension was centrifuged at 4000rpm for 5min, the supernatant was discarded, and 350 μ l TRK Lysis Solution (containing 20% β -mercaptoethanol) was added to each for lysis. Each was then quenched with 350. Mu.l of 70% ethanol (prepared with DEPC water) and mixed by gun blowing.
Transferring the above mixture into HiBind RNA Column column, centrifuging 10000g for 1min, and discarding the filtrate. 500 μl Wash Buffer I was added to each column, and 10000g was centrifuged for 1min, and the filtrate was discarded. Each column was washed 2 times with 500. Mu.l Wash Buffer II, centrifuged at 10000g each for 1min, and the filtrate was discarded. The centrifuge speed was adjusted to the highest speed (17000 g) and centrifuged for 2min to volatilize the ethanol in the column. The column was transferred to a clean 1.5ml centrifuge tube Free of DNA and RNase, left at room temperature for 3-5min, after complete evaporation of ethanol, 50. Mu.l of RNase-Free Water was added to each, incubated for 5min at room temperature, and centrifuged at 17000g for 1min. The filtrate was aspirated again into the column, incubated for 5min at room temperature, and RNA was collected by centrifugation at 17000g for 1min and stored at-80 ℃.
RNA reverse transcription, qPCR reaction
RNA concentration was quantified by using an enzyme-labeled instrument (reading was performed using OD 260/280), and a solution was prepared according to the number of PCR required to be n (n=number of samples+1 tube negative control+1 tube positive control), and 10. Mu.l of a reaction system (2. Mu.l of 5X gDNA digester Buffer, 1. Mu.l of gDNA digestre, 100ng of RNA was prepared per sample, and RNase free ddH was used) 2 O was adjusted to 10. Mu.l in volume, gently mixed by blowing with a gun and incubated at 42℃for 2min. To each sample, 10. Mu.l of 2X Hifair II SuperMix plus was added, and after mixing with gentle blowing by a gun, incubation was performed at 25℃for 5min,42℃for 30min, and 85℃for 5 min.The collected cDNA was placed at-20℃for use.
The cDNA product obtained by reverse transcription is reacted according to qPCR kit. The reaction system is as follows:qPCR SYBR Green Master Mix (No Rox) 10. Mu.l each of the desired forward and reverse primers (forward primer: 5 'AAGCTGAACGACCTGGTTGCTTCA 3', SEQ ID No.10; reverse primer: 5'GGCAGCTTGTAGTTGTAG3', SEQ ID No. 11), 1. Mu.l each of the cDNA templates, and sterile ultra pure water were used to make up a total volume of 20. Mu.l. PCR reaction conditions: the total of 40 cycles of 95 ℃, 5min,95 ℃, 10s,56 ℃, 30s,72 ℃ and 30 s. The expression level of the target gene is 2 compared with that of the reference -△△C And (5) calculating a method.
Conclusion: as shown in FIG. 6, both the novel coronavirus broad-spectrum candidate DNA vaccine pWT and the coronavirus broad-spectrum candidate DNA vaccine pSARS-Omicron Dimer promote transcription of antigen RNA at high levels compared to the empty vector (pVAX 1) after 48 hours of in vitro transfection, and the transcription level of coronavirus broad-spectrum candidate DNA vaccine pSARS-Omicon Dimer group RNA was significantly higher than that of pWT groups.
Example 4: broad-spectrum candidate DNA vaccine immunogenicity verification for coronavirus
To evaluate the immunogenicity of the vaccine prepared in example 2, as well as the effect of the immunization strategy on humoral and cellular immune responses, 6 week old C57BL/6 female mice without specific pathogens were purchased from Shanghai Laek and kept in Ai Diwei Xin Advaccine laboratories (Suzhou) animal facilities. Vaccination with DNA vaccine: the DNA vaccine described in example 1 was injected into the anterior femur muscle sequentially according to different divided injections, followed by Electrical Pulsing (EP). An Electrical Pulse (EP) device consists of two sets of pulses with a constant current of 0.2 Amp. The second pulse set is delayed by 3 seconds. In each group there are two 52ms pulses with a delay between the pulses of 198ms. The first priming was counted as 0 day and the second immunization (booster immunization) was performed on day 14. Experimental grouping: (1) control vector plasmid pVAX125 μg; (2) experimental group wild strain DNA vaccine pWT-25 μg; (3) The experimental group coronavirus broad-spectrum DNA vaccine pSARS-Omicron Dimer-25 mug; blood samples of mice were collected on days 14, 21, and 28, and specific antibodies in serum were measured. On day 28, immunized mice were sacrificed to analyze cellular immune responses.
1. Assessment of antigen-specific humoral immune responses elicited by DNA vaccines
ELISA detection of antibody concentration
ELISA-based methods were used to evaluate RBD protein binding antibodies against SARS-CoV-2 wild-type strain (WT), SARS-CoV-2Beta mutant RBD protein binding antibodies, SARS-CoV-2Delta mutant RBD protein binding antibodies, SARS-CoV-2 Omicron mutant RBD protein binding antibodies, 14 days after primary immunization and 14 days after booster immunization. Nunc 96-well ELISA plates were coated overnight at 4℃with 1. Mu.g/mL of SARS-CoV-2 wild-type strain RBD protein, 1. Mu.g/mL of SARS-CoV-2Beta mutant RBD protein, 1. Mu.g/mL of SARS-CoV-2Delta mutant RBD protein, 1. Mu.g/mL of SARS-CoV-2 Omicron BA.1-type mutant RBD protein (Acro Biosystems, DE, USA), respectively. Plates were washed 3 times and then blocked with 5% Bovine Serum Albumin (BSA) in PBS (0.05% tween 20, i.e. PBST buffer) for 1 hour at 37 ℃. Three times serial dilutions of mouse serum were added to each well and incubated for 1 hour at 37 ℃. The plates were washed five more times and then 1 was added at 37 ℃): after 8000-dilution goat anti-mouse IgG-HRP (GenScript, NJ, CN) incubation for 1 hour, the bound antibodies were subsequently detected. After the final wash, the plate was developed by using TMB substrate and washed with 50. Mu.l/well 2M H 2 SO 4 The reaction was terminated. The end point of the serum antibody titer was determined as the reciprocal of the highest dilution by reading at 450nm and 620nm, and the highest dilution of the sample was 2.1 times higher than the absorbance of the negative control (criterion: control (negative) OD450-620 value +.2.1, determination that the corresponding highest dilution at this OD value was serum antibody titer).
Conclusion: the results of the antibody detection are shown in fig. 7 and 8, and the coronavirus broad-spectrum candidate DNA vaccine pSARS-Omicron Dimer and the new coronavirus wild strain candidate DNA vaccine pWT can obviously excite the experimental animals to generate antigen-specific antibodies 14 days after the primary immunization and 14 days after the booster immunization. In the ELISA test, the SARS-CoV-2 wild strain (WT) RBD protein, the SARS-CoV-2Beta mutant RBD protein, the SARS-CoV-2Delta mutant RBD protein and the SARS-CoV-2 Omicron BA.1 type mutant RBD protein are respectively adopted as external coating antigens, and as can be seen from a result diagram, the novel crown wild strain candidate DNA vaccine pWT can generate antibodies aiming at the novel crown wild type antigen, antibodies aiming at the Beta mutant antigen, the Delta mutant antigen and the Omicron mutant antigen can be generated, however, the pSARS-Omicron Dimer DNA vaccine provided by the invention also has quite remarkable technical effects, and compared with the novel crown wild strain candidate DNA vaccine pWT, the pSARS-Omicron Dimer DNA vaccine provided by the invention has obviously better effects, and as previously mentioned, the novel crown wild strain candidate DNA vaccine pWT is a pre-product with excellent immune effect aiming at the novel wild strain, so that the pSARS-Omicron Dimer DNA vaccine provided by the invention has better immune effect, and has more broad spectrum and better immunity.
1.2. Pseudo virus neutralizing antibody detection
Huh-7 cells were seeded in 96-well plates in DMEM containing 10% FBS for culture. To detect neutralizing antibody titers, mouse serum was serially diluted 1:2 in DMEM medium. Subsequently, the diluted serum samples were incubated with SARS-CoV-2 variant pseudoviruses at 37℃for 30 minutes and the mixture was added to Huh-7 cells for infection. After a further 4 hours incubation, the supernatant was replaced with fresh DMEM medium (containing 10% fbs). After 48 hours of further incubation, the cell supernatant was removed, and the absolute luciferin luminescence values in the lysed cells were detected using a firefly luciferase assay kit (Promega) and a microplate reader and relative values were calculated by normalizing to the virus control wells in the same plate. Neutralizing antibody titers were calculated using GraphPad Prism 9 and defined as the reciprocal of serum dilution (50% reduction in RLU compared to RLU in virus control wells after subtraction of background RLU in cell control wells).
Conclusion: as shown in FIG. 9, the coronavirus broad-spectrum candidate DNA vaccine pSARS-Omicron Dimer can generate good neutralization activity on the viruses such as a novel coronavirus wild strain (WT), a Beta mutant strain, a Delta mutant strain, an Omicron BA.1 type mutant strain and the like on the 14 th day after the booster immunization, and further shows that the pSARS-Omicron Dimer DNA vaccine has good immunogenicity and broad spectrum.
1.3. Pseudo virus neutralizing antibody comparative experiments
Mice were immunized with 25. Mu.g of pSARS-Omicron Dimer DNA vaccine, 25. Mu.g of pWT DNA vaccine, 10. Mu. gZF2001 protein vaccine (recombinant protein vaccine from the market of the ZF2001DNA vaccine) and 25. Mu.g of ZF2001DNA vaccine (DNA vaccine corresponding to the recombinant protein vaccine from the market of the ZF 2001), respectively, and sera from 14 days after the booster immunization were taken for detection of pseudovirus neutralizing antibodies of Omicron mutant strains. The experimental method is consistent with the detection of the pseudo virus neutralizing antibody, and the data is counted in a geometric mean counting mode.
Conclusion: as shown in FIG. 10, against the novel crown Omicron BA.1 type mutant pseudovirus, the coronavirus broad-spectrum candidate DNA vaccine pSARS-Omicron Dimer has a better effect than the novel crown wild type candidate DNA vaccine pWT, the ZF2001 protein vaccine and the ZF2001DNA vaccine, as described above, pWT is a pre-product with excellent immune effect against the novel crown wild type strain, and ZF2001 is a recombinant protein vaccine which is currently marketed, ZF2001DNA is a DNA vaccine corresponding to the ZF2001 protein vaccine, and the above results show that the pSARS-Omicron Dimer DNA vaccine of the present invention has a significantly better immunogenicity against the novel crown Omicron mutant virus than that of pWT, ZF2001 and ZF2001DNA, so that the vaccine of the present invention can be expected to provide excellent preventive protection against the novel crown Omicron mutant strain widely spread in a plurality of regions worldwide.
2. Further evaluation of DNA vaccine-elicited antigen-specific cellular responses
2.1 specific T cell immune response
The effect of vaccine-induced antigen-specific cellular immune responses was further assessed, and splenocytes were isolated 14 days after boost and subjected to flow cytometry detection experiments.
Isolation of spleen cells: at 14 days post boost immunization, mice were euthanized in a sterile environment, spleens were removed and ground into a single cell suspension; cells were harvested by centrifugation, lysed after red blood cell lysate was resuspended, and PBS containing FBS stopped lysis; filtering, and counting the prepared single cell suspension; single cells were suspended in RPMI1640 medium supplemented with 10% fbs,1% penicillin/streptomycin.
Flow cytometry detection experiments: spleen cell suspension from each mouse obtained by the above method, 37 ℃,5% co 2 The following was stimulated with SARS-CoV-2 wild-type RBD peptide library (pool), SARS-CoV-2 Omicron BA.1 mutant RBD peptide library or PMA/Iono, respectively, while blocking (BD, CA, USA) with 1 μg/ml Brefeldin A for 6 hours. Spleen cells were stained for extracellular and intracellular cytokines, stimulated spleen cells were stained with FVD-eFluor780, then washed, and stained with anti-mouse CD4 antibodies in the dark at room temperature for 30 minutes, respectively. Cells were permeabilized with a fixation/permeation buffer and stained for intracellular with anti-mouse IFN-gamma and TNF-alpha at 4℃for 45 min. Cells were washed twice and resuspended with 200 μl PBS, then collected using a flow cytometer (ThermoFisher, MA, usa), and then analyzed with FlowJo software (BD, CA, usa).
Conclusion: the results are shown in figures 11 and 12, and 14 days after boost, both the coronavirus broad-spectrum candidate DNA vaccine, pSARS-omacron Dimer, and the new coronavirus wild-strain candidate DNA vaccine pWT were able to significantly induce the production of antigen-specific CD4 ifnγ and CD4 TNF- α T cell subsets. In the FACS test, the novel coronavirus wild-type RBD protein and the SARS-CoV-2 Omicron BA.1 mutant RBD protein are respectively adopted as in vitro stimulating peptides, and when the novel coronavirus wild-type RBD protein and the SARS-CoV-2 Omicron BA.1 mutant RBD protein are adopted as in vitro stimulating peptides, the novel coronavirus wild-type nucleic acid vaccine pWT is beneficial, however, the coronavirus broad-spectrum candidate DNA vaccine pSARS-Omicron Dimer provided by the invention also has quite remarkable technical effects. And when SARS-CoV-2 Omicron BA.1 type mutant strain RBD protein is adopted as in vitro stimulating peptide, the coronavirus broad-spectrum candidate DNA vaccine pSARS-Omicron Dimer provided by the invention has a remarkable better effect than the novel crown wild strain candidate DNA vaccine pWT, and pWT is a pre-product with excellent immune effect aiming at the novel crown wild strain, thus more demonstrating that the pSARS-Omicron Dimer DNA vaccine provided by the invention has better immunogenicity and broad spectrum.
Example 5: verification of protection effect of coronavirus broad-spectrum candidate DNA vaccine for preventing new coronavirus infection
In order to further examine the actual effect of the pSARS-Omicron Dimer DNA vaccine of the invention on preventing mice from being infected with new coronaviruses, whether the mice are protected after virus infection or not, experiments were further carried out by using a human ACE2 (hACE 2) transgenic mouse (C57 BL/6 background) model. Experimental grouping: (1) control vector plasmid pVAX 1. Mu.g; (2) The experimental group coronavirus broad-spectrum DNA vaccine pSARS-Omicron Dimer-20 mug; the DNA vaccine was vaccinated in the same manner as in example 4, with the time of vaccination being the first immunization on day 0, the second immunization (booster immunization) on day 21, and the specific antibodies in serum were measured on day 17 after the second immunization. Mice were infected with virus at day 18 post-priming and lung tissue viral load was measured at day 4 post-infection.
ELISA detection of antibody concentration
IgG antibody titer in serum was measured 17 days after boosting, and the experimental method was the same as ELISA method in example 4, and the SARS-CoV RBD protein binding antibody was additionally measured in this experiment, and was coated overnight with 1. Mu.g/mL SARS-CoV RBD protein (Acro Biosystems, DE, USA).
Conclusion: the results of the antibody detection are shown in FIG. 13, and the coronavirus broad-spectrum candidate DNA vaccine pSARS-Omicron Dimer was able to significantly excite hACE2 transgenic mice to produce high levels of antigen-specific antibodies 17 days after booster immunization. From the results, it can be seen that the coronavirus broad-spectrum candidate DNA vaccine pSARS-Omicron Dimer can generate antibodies against not only the novel coronal wild-type antigen, but also Beta mutant strain antigen, delta mutant strain antigen, omicron BA.1 type mutant strain antigen and SARS-CoV antigen, and further demonstrates that the pSARS-Omicron Dimer DNA vaccine of the invention has good immunogenicity and broad spectrum.
2. Pseudo virus neutralizing antibody detection
Serum was collected 17 days after boost and the neutralizing antibody titer was measured. This experiment examined the neutralizing ability of the novel Omicron ba.1 mutant and Omicron ba.2 mutant viruses. The experimental method comprises the following steps: will be 3x10 4 293-ACE2 cells/well were cultured in DMEM containing 10% FBSIn 96-well plates. To detect neutralizing antibody titers, mouse serum (starting from 1:30 dilution) was serially diluted 1:3 in DMEM medium for a total of 6 dilutions. Antibody XG05 (0.1 mg/mL) was used as a Positive Control (Positive Control). Subsequently, the diluted serum samples were combined with pseudoviruses of the new coronal mutants (1 x10 3 TCID 50 Well) after incubation at 37 ℃ for 1 hour the mixture was added to 293-ACE2 cells for infection, cell supernatants were removed after 48 hours of incubation, absolute luciferin luminescence values in the lysed cells were detected using firefly luciferase assay kit (Promega) and a microplate reader, and relative values were calculated by normalizing to virus control wells in the same plate. Neutralizing antibody titers were calculated using GraphPad Prism 9 and defined as the reciprocal of serum dilution (50% reduction in RLU compared to RLU in virus control wells after subtraction of background RLU in cell control wells).
Conclusion: the detection results of the neutralizing antibodies are shown in fig. 14 and 15, and the result shows that the broad-spectrum candidate DNA vaccine pSARS-Omicron Dimer can generate good neutralizing activity on viruses such as new Omicron BA.1 mutant strain, omicron BA.2 mutant strain and the like on the 17 th day after the booster immunization, so that the pSARS-Omicron Dimer DNA vaccine has excellent preventive and protective effects on the new Omicron mutant strain.
3. Pulmonary viral load detection
Mice were infected with omacron ba.1 mutant virus at day 18 post boost, lung tissue was harvested at day 4 post infection, and lung tissue viral load was measured using qPCR. The experiments entrusted with the experiments of the Changchun military veterinary institute BSL-3 laboratory completes the new crown Omicron BA.1 virus infection experiment. Viral RNA was isolated from lung tissue using QIAamp Viral RNA Kit (Qiagen, 52906) following the manufacturer's instructions; the virus copies were then detected by RT-qPCR using an ABI 7500 real-time PCR system (Applied Biosystems, CA, united States) using HiScript II One Step RT-qPCR SYBR Green Kit (Vazyme Biotech, nanj, china). The reaction conditions for RT-qPCR were as follows: 50℃for 15 minutes, 95℃for 30 seconds, then 45 cycles at 95℃for 10 seconds and 63℃for 35 seconds. Specific primers for detecting SARS-CoV-2N gene and SgE gene are:
N-gene-F,GACCCCAAAATCAGCGAAAT(SEQ ID No.12);
N-gene-R,TCTGGTTACTGCCAGTTGAATCTG(SEQ ID No.13);
sgRNA-E-F,CGATCTCTTGTAGATCTGTTCTC(SEQ ID No.14);
sgRNA-E-R,ATATTGCAGCAGTACGCACACA(SEQ ID No.15)。
Conclusion: pulmonary viral load results as shown in fig. 16 and 17, gRNA detected viral N gene, and detection of gRNA indicated the presence of virus in lung tissue, indicating that the virus infected lung tissue; the sgrnas are intermediates for the replication of new coronaviruses, if detected they indicate that the virus infects the cell and self-replicates using the environment of the host cell. From the results, the pVAX1 control group detected higher gRNA gene and sgRNA gene, indicating that the virus infected cells and replicated in the cells; compared with a control group, the gRNA and sgRNA levels of the pSARS-Omicron Dimer DNA vaccine group are obviously reduced, which proves that the pSARS-Omicron Dimer DNA vaccine can effectively prevent or inhibit the replication of viruses in vivo and has good vaccine protection effect.
From the results of examples 1 to 5, it can be seen that the coronavirus broad-spectrum candidate DNA vaccine pSARS-Omicron Dimer of the present invention can be effectively transcriptionally expressed in mammalian cells due to an effective codon optimization system and reasonable sequence design; the pSARS-Omicron Dimer candidate DNA vaccine can obviously excite experimental animals to generate antigen specific antibodies for new crown wild type antigens, can generate antibodies for new crown Delta mutant strain antigens, beta mutant strain antigens, omicron mutant strain antigens and SARS-CoV antigens, and has good neutralizing activity; for cellular immune responses, the pSARS-Omicron Dimer DNA vaccine was able to induce the production of higher levels of antigen-specific CD4 IFNγ and CD4 TNF- α T cell subsets against the novel coronal wild-type antigen and the Omicron mutant antigen; meanwhile, the DNA vaccine can effectively prevent or inhibit the replication of the novel crown Omicron mutant virus in vivo, and has good vaccine protection effect. The experiments above show that the pSARS-Omicron Dimer DNA vaccine has good immunogenicity and broad spectrum.
Notably, the pWT wild strain vaccine is a product of the company aiming at SARS-CoV-2 wild strain in the early stage, and has very excellent immune effect in the phase III clinic. In the above-described experiments, for example, ELISA, pseudo-virus neutralization and FACS detection, an antigen-specific immune response was detected using not only the novel coronaSARS-CoV-2 wild-type RBD protein or virus as an in vitro coating antigen or stimulating peptide, but also the SARS-CoV-2Beta mutant RBD protein or virus, the SARS-CoV-2Delta mutant RBD protein or virus and the SARS-CoV-2 Omicron mutant RBD protein or virus as an in vitro coating antigen or stimulating peptide. Even when the conditions are obviously more favorable for the novel crown wild type nucleic acid vaccine pWT (the novel crown SARS-CoV-2 wild type RBD protein is adopted), the pSARS-Omicron Dimer DNA vaccine provided by the invention achieves obvious technical effects and is even better than the novel crown wild type nucleic acid vaccine pWT, and further illustrates that the pSARS-Omicron Dimer DNA vaccine provided by the invention has better immunogenicity and broad spectrum. Whereas the pSARS-Omicron Dimer DNA vaccine of the invention clearly elicits higher humoral and cellular immunity levels when the SARS-CoV-2Beta mutant RBD protein or virus, the SARS-CoV-2Delta mutant RBD protein or virus, or the SARS-CoV-2 Omicron mutant RBD protein or virus is used as an in vitro coating antigen or stimulating peptide.
Meanwhile, ZF2001 is a recombinant protein vaccine which is marketed at present, ZF2001 DNA is a DNA vaccine aiming at the ZF2001 protein vaccine, and in a pseudo-virus neutralization experiment aiming at an Omicron mutant strain, the pSARS-Omicron Dimer DNA vaccine provided by the invention is obviously superior to pWT, the ZF2001 protein vaccine and the ZF2001 DNA vaccine, so that the pSARS-Omicron Dimer DNA vaccine has better immunogenicity aiming at a new crown Omicron mutant strain virus.
The broad-spectrum candidate DNA vaccine pSARS-Omicron Dimer can generate good neutralization activity on viruses such as new crown Omicron BA.1 mutant strain, omicron BA.2 mutant strain and the like on day 17 after the booster immunization, and the pSARS-Omicron Dimer DNA vaccine has excellent preventive protection effect on the new crown Omicron mutant strain. Compared with a control group, the gRNA and sgRNA levels of the pSARS-Omicron Dimer DNA vaccine group are obviously reduced, which proves that the pSARS-Omicron Dimer DNA vaccine can effectively prevent or inhibit the replication of viruses in vivo and has good vaccine protection effect.
Thus, it is expected that the vaccine of the present invention can provide excellent preventive protection against a novel crown Omicron mutant which is widely spread in many countries and regions around the world.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.

Claims (10)

1. A recombinant nucleic acid molecule comprising any one of (a) to (c) as follows:
(a) The recombinant DNA molecules comprise a first DNA molecule encoding the RBD region of SARS-CoV S protein and a second DNA molecule encoding the RBD region of S protein of the novel SARS-CoV-2Omicron mutant strain;
(b) A DNA molecule derived from (a) by substitution, deletion or addition of one or several nucleotides in the nucleotide sequence of the recombinant DNA molecule defined in (a) and having the function of encoding the RBD region of SARS-CoV S protein and encoding the RBD region of S protein of the novel SARS-CoV-2Omicron mutant;
(c) Nucleic acid molecules which hybridize under stringent conditions with the nucleotide sequence of the recombinant DNA molecule defined in (a) or the DNA molecule defined in (b) and which encode the RBD region of the SARS-CoV S protein and the RBD region of the S protein of the novel SARS-CoV-2Omicron mutant strain.
2. The recombinant nucleic acid molecule of claim 1, wherein the first DNA molecule encodes an amino acid sequence as set forth in SEQ ID No. 1; the amino acid sequence of the second DNA molecule is shown as SEQ ID No. 2.
3. The recombinant nucleic acid molecule of claim 2, wherein the nucleotide sequence of the first nucleic acid molecule is set forth in SEQ ID No. 3; the nucleotide sequence of the second nucleic acid molecule is shown as SEQ ID No. 4;
preferably, the nucleotide sequence of the recombinant nucleic acid molecule is the nucleotide sequence shown as SEQ ID No.5, or has at least 90% identity with the nucleotide sequence shown as SEQ ID No.5, and encodes the RBD region of SARS-CoV S protein and the RBD region of novel SARS-CoV-2Omicron mutant S protein.
4. A biomaterial, comprising:
a construct comprising the recombinant nucleic acid molecule of any one of claims 1 to 3; and, a third nucleic acid molecule encoding a signal peptide linked to the 5' end of the recombinant nucleic acid molecule;
(ii) recombinant expression vectors, including original expression vectors; and, inserting into the original expression vector a coding nucleic acid fragment selected from the group consisting of the recombinant nucleic acid molecule of any one of claims 1 to 3 or the (i) construct; preferably, the original expression vector is a pVAX1 plasmid;
(iii) a transformant obtained by introducing the recombinant expression vector of (ii) into a host cell selected from the group consisting of insect cells, yeast, avian cells, and mammalian cells; preferably, the host cell is HEK293, CHO or COS-7;
(iv) a polypeptide comprising a polypeptide encoded by the recombinant nucleic acid molecule of any one of claims 1 to 3, a polypeptide encoded by the construct of (i), or a polypeptide obtained by expression of a transformant of (iii);
(V) an antibody that specifically binds to the (IV) polypeptide.
5. The biological material of claim 4, wherein the signal peptide encoded by the third nucleic acid molecule comprises the following (c) or (d):
(c) A signal peptide with an amino acid sequence shown as SEQ ID No. 6;
(d) A signal peptide derived from (c) having a signal peptide function by substituting, deleting or adding one or more amino acids in the amino acid sequence of the signal peptide defined in (c).
6. Use of a recombinant nucleic acid molecule according to any one of claims 1 to 3 or a biological material according to any one of claims 4 to 5 in (a) or (B) as follows:
(A) Preparing vaccine for preventing and/or treating SARS-CoV and/or SARS-CoV-2 virus infection;
(B) Preparing medicine for preventing and/or treating SARS-CoV and/or SARS-CoV-2 virus-induced related diseases.
7. The use according to claim 6, wherein the SARS-CoV-2 virus comprises a wild-type strain, a B.1.617.2 mutant, a B.1.1.7 mutant, a B.1.351 mutant, a P.1 mutant, a B.1.2 mutant, a B.1 mutant, a B.1.621 mutant, a B.1.525 mutant, a B.1.526 mutant, a C.37 mutant, a B.1.617.1 mutant or a B.1.1.529 mutant.
A DNA vaccine comprising the recombinant nucleic acid molecule of any one of claims 1 to 3 or the recombinant expression vector of any one of claims 4 to 5.
9. The DNA vaccine of claim 8, further comprising at least one of a pharmaceutically acceptable adjuvant, carrier, diluent, or excipient;
and/or at least one drug having a therapeutic effect on SARS-CoV and/or SARS-CoV-2 virus;
preferably, the adjuvant comprises at least one of an aluminium adjuvant, TLRs ligand, metal ion, cytokine or chemokine adjuvant;
further preferably, the metal ions includeMn 2+ And/or Zn 2+
10. The method for producing a DNA vaccine according to claim 8 or 9, comprising introducing the recombinant nucleic acid molecule according to any one of claims 1 to 3 or the recombinant expression vector according to any one of claims 4 to 5 into a host cell, culturing the host cell, and extracting the recombinant nucleic acid molecule or the recombinant expression vector from the host cell.
CN202210874769.0A 2022-07-25 2022-07-25 Recombinant DNA molecule for encoding coronavirus antigen, DNA vaccine and application Pending CN117448355A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210874769.0A CN117448355A (en) 2022-07-25 2022-07-25 Recombinant DNA molecule for encoding coronavirus antigen, DNA vaccine and application

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210874769.0A CN117448355A (en) 2022-07-25 2022-07-25 Recombinant DNA molecule for encoding coronavirus antigen, DNA vaccine and application

Publications (1)

Publication Number Publication Date
CN117448355A true CN117448355A (en) 2024-01-26

Family

ID=89580487

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210874769.0A Pending CN117448355A (en) 2022-07-25 2022-07-25 Recombinant DNA molecule for encoding coronavirus antigen, DNA vaccine and application

Country Status (1)

Country Link
CN (1) CN117448355A (en)

Similar Documents

Publication Publication Date Title
EP4357368A1 (en) Recombinant sars-cov-2 rbd tripolymer protein vaccine capable of generating broad-spectrum cross-neutralization activity, preparation method therefor, and application thereof
CN112626090B (en) Nucleotide sequence for coding novel coronavirus antigen and application thereof
CN109182380B (en) Preparation method and application of baculovirus-expressed classical swine fever E2 subunit vaccine
CN111019910B (en) F genotype mumps virus attenuated strain, construction method and application thereof
CN112011521A (en) Novel recombinant newcastle disease virus vector coronavirus vaccine candidate strain as well as construction method and application thereof
CN113528549B (en) DNA molecule for encoding novel coronavirus B.1.351 mutant strain antigen, DNA vaccine and application
CN111035755A (en) Type 1diabetes vaccine and preparation method thereof
CN111304253A (en) African swine fever virus vaccine, preparation method and application thereof
CN113528545B (en) Nucleic acid sequence for coding novel coronavirus B.1.1.7 mutant strain antigen and application thereof
CN112399854A (en) Vaccine composition for preventing or treating severe fever with thrombocytopenia syndrome (SFTS) viral infection
CN112500458A (en) Novel variant subunit vaccine of chicken infectious bursal disease virus, preparation method and application thereof
CN114989266B (en) African swine fever virus pA104R protein immunosuppression related amino acid site and application thereof
CN113528546B (en) DNA molecule for encoding novel coronavirus P.1 mutant strain antigen, DNA vaccine and application
CN115975053A (en) Vaccine targeting novel coronaviruses
CN117448355A (en) Recombinant DNA molecule for encoding coronavirus antigen, DNA vaccine and application
CN109517044B (en) Porcine epidemic diarrhea virus genetic engineering antigen and antibody
CN114315984A (en) N protein epitope mutation marker for preparing PRRSV gene II type epitope deletion vaccine strain and application thereof
CN117448362A (en) Recombinant DNA molecule for encoding coronavirus antigen, DNA vaccine and application
CN117448354A (en) Recombinant DNA molecule for encoding coronavirus antigen, DNA vaccine and application
CN109568574B (en) Application of sPD1 protein and/or sPD1 gene as immune adjuvant
CN112159480A (en) Chicken infectious bursal disease virus multi-antigen epitope protein and application thereof
CN114573667B (en) Mutant strain DNA vaccine of SARS-CoV-2 virus B.1.1.529 and application thereof
CN113862285B (en) SARS-COV-2 virus B.1.617.2 mutant strain DNA vaccine and application
CN105218679A (en) Human metapneumovirus multi-epitope antigen and application thereof
CN117442712A (en) Kit for realizing coronavirus priming-boosting immunity and preparation method and application thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination