Search

CN-121991247-A - Avian infectious bronchitis subunit vaccine based on nano-skeleton technology

CN121991247ACN 121991247 ACN121991247 ACN 121991247ACN-121991247-A

Abstract

The invention relates to a chicken infectious bronchitis subunit vaccine based on a nano-skeleton technology. The invention provides fusion protein which sequentially comprises an S protein fragment of chicken infectious bronchitis virus or a mutant thereof, a connecting peptide and helicobacter pylori ferritin from an N end to a C end, wherein the S protein fragment of chicken infectious bronchitis virus is S1 protein, the amino acid sequence of the S protein fragment of chicken infectious bronchitis virus is shown as SEQ ID NO.2, the mutant of the S protein fragment of chicken infectious bronchitis virus is S1-2 protein or S1-3 protein, the amino acid sequence of the S1-2 protein is shown as SEQ ID NO.4, and the amino acid sequence of the S1-3 protein is shown as SEQ ID NO. 5.

Inventors

  • LAN QING
  • SONG CHUNYU

Assignees

  • 北京鼎持生物技术有限公司
  • 浙江鼎持生物制品有限公司

Dates

Publication Date
20260508
Application Date
20251121

Claims (11)

  1. 1. The fusion protein sequentially comprises a chicken infectious bronchitis virus S protein fragment or mutant thereof, a connecting peptide and helicobacter pylori ferritin from the N end to the C end, The S protein fragment of the avian infectious bronchitis virus is S1 protein, and the amino acid sequence of the S protein fragment is shown as SEQ ID NO. 2; The mutant of the S protein fragment of the avian infectious bronchitis virus is S1-2 protein or S1-3 protein, wherein the amino acid sequence of the S1-2 protein is shown as SEQ ID NO.4, and the amino acid sequence of the S1-3 protein is shown as SEQ ID NO. 5.
  2. 2. A fusion protein according to claim 1 or 2, wherein the amino acid sequence of helicobacter pylori ferritin is shown in SEQ ID No. 17.
  3. 3. The fusion protein according to claim 1 or 2, wherein the nucleotide sequence of the S1 protein is shown as SEQ ID NO.10, the nucleotide sequence of the S1-2 protein is shown as SEQ ID NO.12, and the nucleotide sequence of the S1-3 protein is shown as SEQ ID NO. 13; Optionally, the nucleotide sequence of the helicobacter pylori ferritin is shown as SEQ ID NO. 18.
  4. 4. A fusion protein according to claim 1 or 2, wherein the linker peptide is selected from the group consisting of [ A (EAAAK) nA ], (GGGGS) n, (G) n, (XP) n, preferably having the amino acid sequence shown in SEQ ID NO. 19.
  5. 5. The fusion protein of claim 1 or 2, further comprising a purification tag, such as His, fc, HA, GST, flag, MBP or FLAG tag.
  6. 6. A polynucleotide molecule encoding the fusion protein of any one of claims 1-5.
  7. 7. A vector comprising the polynucleotide molecule of claim 6.
  8. 8. A host cell expressing the fusion protein of any one of claims 1-5, and/or comprising the polynucleotide molecule of claim 6, and/or comprising the vector of claim 7.
  9. 9. A vaccine composition comprising the fusion protein of any one of claims 1-5, optionally further comprising an immunologically and pharmaceutically acceptable carrier or adjuvant.
  10. 10. Use of the fusion protein of any one of claims 1-5, the polynucleotide molecule of claim 6, the vector of claim 7, the host cell of claim 8, the vaccine composition of claim 9 in the manufacture of a medicament for the treatment and/or prophylaxis of Infectious Bronchitis Virus (IBV) infection, or infectious bronchitis in chickens.
  11. 11. The preparation method of the Infectious Bronchitis Virus (IBV) vaccine is characterized by comprising the following steps: (1) Constructing a polynucleotide molecule of claim 6; (2) Expressing the fusion protein of any one of claims 1-5 in a host cell, preferably, the host cell is a CHO cell; (3) Purifying the expressed fusion protein to prepare the vaccine.

Description

Avian infectious bronchitis subunit vaccine based on nano-skeleton technology Technical Field The invention belongs to the field of genetic engineering, and in particular relates to a recombinant protein subunit vaccine of Infectious Bronchitis Virus (IBV) and a preparation method thereof. Background Infectious bronchitis (Avian Infectious bronchitis, IB) is an acute, highly contagious disease of chicken caused by infectious bronchitis virus (Avian Infectious bronchitis virus, IBV), which is listed as a legally reported animal epidemic by the world animal health Organization (OIE), which is listed as a second type of animal epidemic in our country. The disease is characterized by reduced respiratory symptoms, nephritis and production performance, particularly high mortality rate is caused after the broiler chicken generates kidney-shaped branch transfer characterized by kidney swelling, the death rate of white feather broiler chicken can reach more than 30%, the mortality rate of high-quality broiler chicken can be about 15%, the weight gain and feed return of the sick broiler chicken are reduced, and the quality of the broiler chicken is reduced due to air sac inflammation caused by mixed infection of escherichia coli, mycoplasma and the like. The egg chicks can cause permanent irreversible damage to reproductive systems besides death, and the egg chicks are characterized by dysplasia of fallopian tubes and ovaries or massive water accumulation cysts of fallopian tubes and uterus, so that the egg chicks are characterized by no egg laying peak, and the egg laying quantity and egg laying quality are reduced, and white eggs, soft shell eggs, yarn eggs and malformed eggs are produced. Part of IBV strains can also cause lesions in the intestinal tract, adenoma stomach, muscles. IB can cause harm to chickens of all ages and varieties, causes huge economic loss to the global poultry industry, and is a serious infectious disease seriously affecting the world poultry industry. Clinical signs of IB include sneezing, tracheal tube, nasal discharge and wheezing. The weight of the broiler birds is reduced, while the laying birds lay fewer eggs of poorer quality. Respiratory tract infections predispose chickens to secondary bacterial infections, which can be fatal to chickens. Viruses can also cause permanent damage to the oviduct, particularly in chickens, resulting in reduced egg production and quality, and to the kidneys, sometimes leading to fatal kidney disease. IBV has been reported to cause more economic losses to the poultry industry than any other infectious disease. To date, vaccine immunization is still the most commonly used and most effective measure for controlling IB in production, and currently domestic declared IBV vaccines are mainly divided into 1) whole virus inactivated vaccines, wherein the duration of the immune response induced by the whole virus inactivated vaccine is shorter, and only antibody production is induced, but T cell immune response cannot be mediated. The immune effect is determined by the dosage and the antigen content in the vaccine, and the immunization is often carried out by a dosage which is many times higher than that of the live vaccine, and an adjuvant is also required to be added, so that the production cost of the vaccine can be increased, and the popularization and the application of the vaccine are limited. 2) Live attenuated vaccine is prepared through the steps of time and labor consuming, in vivo mutation, recombination and virulence return, mother source antibody neutralization, reduction of vaccine response to recombinant DNA vaccine, effective carrier delivery, strict preparation technology and possible change of protein immunogenicity through post-translational protein modification. Subunit vaccine has natural components of complete organism, only has main virus surface protein, avoids producing a plurality of antibodies induced by irrelevant antigens, reduces side reaction of the vaccine, related diseases and virulence return caused by the vaccine, and the like. The subunit vaccine has the advantages of good safety, capability of reducing or eliminating heat sources, allergens, immunosuppressive agents or other harmful reactants which are difficult to avoid by conventional live vaccines or inactivated vaccines, good stability of the vaccine, convenience in storage and transportation, capability of distinguishing the generated immune response from the response generated by wild virus infection, convenience in controlling and eliminating epidemic diseases, and capability of mass production. However, subunit vaccines have the obvious defects of high production cost, lower immunogenicity than attenuated vaccines and inactivated vaccines, and limited application. The subunit vaccine is used as a third needle vaccine for enhancing immunity, has a great market and has important significance. IBV belongs to the family coronaviridae and is a representative strain of coron