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KR-20260066090-A - New DEV vector

KR20260066090AKR 20260066090 AKR20260066090 AKR 20260066090AKR-20260066090-A

Abstract

The present invention relates to the field of animal health. In particular, the present invention relates to attenuated duck enteritis virus (DEV). More particularly, the present invention relates to attenuated DEV that is non-pathogenic or exhibits reduced pathogenicity in ducks and chickens. Furthermore, the present invention relates to a composition comprising the attenuated DEV of the present invention as a vector-vaccine for poultry, and to the use thereof.

Inventors

  • 마 쳉타이
  • 황푸 이판
  • 첸 닝
  • 추이 샤오핑
  • 주 시디
  • 장 칭슈이

Assignees

  • 베링거 잉겔하임 베트메디카 (차이나) 코포레이션 리미티드

Dates

Publication Date
20260512
Application Date
20240823
Priority Date
20230825

Claims (20)

  1. An attenuated duck enteritis virus (DEV), wherein one or more genes of the DEV genome selected from the group consisting of US3, UL24, UL40, UL39, and UL23 are inactivated.
  2. An attenuated duck enteritis virus (DEV), comprising an inactivated gene selected from any one of i) the US3 gene; ii) the UL24 gene; iii) the UL40 gene; iv) the UL39 gene; and v) the UL23 gene, in combination with the inactivation of one or more additional non-essential genes of the DEV.
  3. In paragraph 2, one or more additional non-essential genes of the DEV are different from the first inactivation gene and are selected from i) the UL2 gene, ii) the UL41 gene; iii) the US3 gene; iv) the UL24 gene; v) the UL40 gene; vi) the UL39 gene; or vii) the UL23 gene, in an attenuated DEV.
  4. As an attenuated duck enteritis virus (DEV), i) US3 gene; ii) UL24 gene; iii) UL40 gene; iv) UL39 gene; v) UL23 gene; vi) UL24 gene and UL2 gene; vii) UL40 gene and UL2 gene; or viii) An attenuated DEV comprising an inactivated gene(s) selected from either the UL23 gene and the UL41 gene.
  5. In any one of claims 1 to 4, the attenuated DEV, wherein the inactivation of the selected gene causes attenuation of the DEV.
  6. In any one of claims 1 to 5, the attenuated DEV, wherein the gene is inactivated by mutation, interruption, replacement, or deletion of part or all of the gene sequence.
  7. An attenuated DEV according to any one of claims 1 to 6, wherein at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% of the sequence of the gene is replaced or deleted.
  8. An attenuated DEV according to any one of claims 1 to 7, wherein the attenuated DEV further comprises a heterogeneous polynucleotide encoding a heterogeneous antigen.
  9. In paragraph 8, the above heterologous antigen is an attenuated DEV that is an antigen of a poultry pathogen.
  10. An attenuated DEV according to claim 8 or 9, wherein the heterogeneous polynucleotide is inserted into a non-essential gene of the attenuated DEV.
  11. In any one of claims 8 to 10, the attenuated DEV, wherein the heterogeneous polynucleotide is expressed after the attenuated DEV is transfected into a suitable host cell.
  12. In any one of paragraphs 1 to 11, an attenuated DEV for use as a vector vaccine in poultry.
  13. In any one of paragraphs 1 to 12, an attenuated DEV for use as a vector vaccine in ducks.
  14. In any one of paragraphs 1 to 13, an attenuated DEV for use as a vector vaccine in chickens.
  15. A composition comprising a weakened DEV according to any one of claims 1 to 11.
  16. In item 15, the composition is a vaccine.
  17. A method of vaccinating poultry by inducing a protective immune response in poultry against a pathogen, comprising at least one administration of the composition of claim 15 or 16 or the vector vaccine of any one of claims 12 to 14.
  18. A composition of claim 15 or 16 or a vector vaccine of any one of claims 12 to 14 for use in a method of inducing a protective immune response in poultry against a poultry pathogen, comprising administering the composition of claim 15 or 16 or the vector vaccine of any one of claims 12 to 14 to poultry one or more times.
  19. The method of claim 17 or the use of claim 18, wherein the poultry is a duck or a chicken.
  20. The method of claim 17 or 19 or the use of claim 18 or 19, wherein the above poultry is 1 day old, 2 days old, 3 days old, 4 days old, 5 days old, 6 days old, or 7 days old on the vaccination date.

Description

New DEV vector Cross-reference regarding related applications This application claims priority to PCT/CN2023/114895, filed on August 25, 2023, under the title of the invention “Attenuated DEV,” the full text of which is incorporated herein by reference. Technology field The present invention relates to the field of animal health. In particular, the present invention relates to attenuated Duck Enteritis Virus (DEV). More particularly, the present invention relates to attenuated DEV that is non-pathogenic or exhibits reduced pathogenicity in poultry. Furthermore, the present invention relates to a composition comprising the attenuated DEV of the present invention as a vector-vaccine for poultry, and to the use thereof. Duck plague, also known as duck viral enteritis, is an acute septicemic infection in Anseriformes , such as ducks and geese. It is caused by the duck enteritis virus (DEV), which naturally infects ducks and geese. However, DEV not only causes duck plague in ducks and geese but also infects and kills chickens. DEV is also known as Anatid herpesvirus, duck herpesvirus, duck viral enteritis virus (DVEV), or duck plague virus (DPV). The complete nucleotide sequence of DEV has been determined and is available online (see, for example, Genbank registry number JQ673560). The viral genome contains approximately 162 kb and encodes nearly 80 different proteins. Several DEV strains, such as the Jansen strain, CSC strain, CHv strain, VAC strain, and 2085 strain, have been isolated. The full sequences of several DEV strains, such as VAC strain: ID EU082088.2; Anatid isolate C-KCE: ID KF263690.1; Anatid strain CHv: ID JQ647509.1; Anatid strain 2085: ID JF999965; Anatid strain CV: ID KJ549663.1 or Anatid strain CSC: ID JQ673560.1, are available in Genbank. As a member of the herpesvirus family, the DEV genome possesses a stable double-stranded DNA structure and contains multiple non-essential regions for viral replication, which can facilitate the insertion of multiple heterologous genes. DEV strains attenuated through traditional passage in chicken or duck embryos have become a promising live vaccine vector system for the development of vaccines against avian diseases. However, attenuation via traditional passage in chicken or duck embryos results in non-specific and mostly unknown genetic modifications, posing a risk that these modifications may be lost, allowing the attenuated virus to regain its virulence. Currently, the expression of heterologous genes using DEV as a vector is being primarily studied for the development of vaccines against diseases in ducks. It has been reported that DEV vectorized vaccines expressing heterologous genes are safe in ducks but toxic in chickens (cf. Wang, J., (2015). Construction of a recombinant duck enteritis virus (DEV) expressing hemagglutinin of H5N1 avian influenza virus based on an infectious clone of DEV vaccine strain and evaluation of its efficacy in ducks and chickens. Virology Journal, 12(1).). Developing genetically modified, safe, and effective live DEV vectors for the development of vaccines against diseases in poultry remains a challenge for the industry. The present invention is based on the surprising discovery that a DEV containing inactivated genes within the genome, e.g., i) US3 gene; ii) UL24 gene; iii) UL40 gene; iv) UL39 gene; or v) UL23 gene, either alone or in combination with other DEV genes, such as, e.g., vi) UL24 gene and UL2 gene; vii) UL40 gene and UL2 gene; or viii) UL23 gene and UL41 gene, reduces or eliminates mortality in ducks and chickens compared to a non-modified DEV. While wild-type DEV is lethal to young ducks and chickens, the DEV of the present invention is safe and can effectively deliver and express genes of interest in vivo . In particular, these DEVs can (i) be attenuated in vivo , particularly in ducks and chickens, and (ii) express foreign genes in a manner suitable for inducing protective immunity, including during very early stages (i.e., day 0, day 1, day 2, or day 3 after hatching). Additionally, these attenuated DEVs maintain a rapid growth rate, enabling the production of high titers. Therefore, these DEVs represent a very potent vector for vaccinating non-human animals, particularly poultry, and conferring early protective immunity. In one aspect, the present invention provides an attenuated duck enteritis virus (DEV) in which one or more genes of the DEV genome selected from the group consisting of US3, UL24, UL40, UL39, and UL23 are inactivated. In one aspect, the present invention provides an attenuated duck enteritis virus (DEV) comprising an inactivation gene selected from any one of i) the US3 gene; ii) the UL24 gene; iii) the UL40 gene; iv) the UL39 gene; and v) the UL23 gene, either alone or in combination with any other non-essential gene of DEV. In one aspect, the present invention provides an attenuated duck enteritis virus (DEV) comprising inactivation gene(s) selected from any one of i) US3 gene; ii) UL2