CN-122011217-A - Fusion protein and nucleic acid vaccine for preventing and treating various pathogenic Pasteurella bacterial infections and application thereof

Abstract

The invention discloses a fusion protein and a nucleic acid vaccine for preventing and treating various pathogenic Pasteurella bacterial infections and application thereof. The fusion proteins comprise six antigens rplE, rpsC, rpsE, EF-Tu, dnaK, EF-G or three antigens EF-Tu, dnaK, EF-G, which are highly conserved among the various Pasteurella bacteria. The invention also provides recombinant nucleic acid molecules encoding the fusion proteins, immunogenic compositions and recombinant vaccines comprising the same. The vaccine can induce broad-spectrum cross immunity protection, and is used for preventing and treating infectious diseases caused by Pasteurella multocida, haemophilus parasuis, haemophilus haemolyticus, haemophilus influenzae and haemophilus parasuis.

Inventors

• HAN TIYUN
• XU SHI
• LI JING
• XU MENGWEI

Assignees

• 南京澄实生物医药科技有限公司

Dates

Publication Date

20260512

Application Date

20260413

Claims (11)

1. 1. A fusion protein, which is characterized in that the fusion protein comprises EF-Tu antigen or an antigenic fragment thereof, dnaK antigen or an antigenic fragment thereof and EF-G antigen or an antigenic fragment thereof; Or the fusion protein comprises rplE antigen or an antigenic fragment thereof, rpsC antigen or an antigenic fragment thereof, rpsE antigen or an antigenic fragment thereof, EF-Tu antigen or an antigenic fragment thereof, dnaK antigen or an antigenic fragment thereof, and EF-G antigen or an antigenic fragment thereof; The amino acid sequence of rplE antigen is shown as SEQ ID NO. 1, the amino acid sequence of rpsC antigen is shown as SEQ ID NO. 2, the amino acid sequence of rpsE antigen is shown as SEQ ID NO. 3, the amino acid sequence of EF-Tu antigen is shown as SEQ ID NO. 4, the amino acid sequence of DnaK antigen is shown as SEQ ID NO. 5, and the amino acid sequence of EF-G antigen is shown as SEQ ID NO. 6.
2. 2. The fusion protein of claim 1, wherein the antigens are optionally linked by a linker peptide sequence having the amino acid sequence shown in SEQ ID NO.7 or a spacer sequence having the amino acid sequence shown in SEQ ID NO. 8.
3. 3. The fusion protein of claim 2, wherein the amino acid sequence of the fusion protein is shown in SEQ ID NO. 9 or SEQ ID NO. 10.
4. 4. A recombinant nucleic acid molecule encoding the fusion protein of claim 1, said recombinant nucleic acid molecule having the nucleotide sequence set forth in SEQ ID No. 12 or SEQ ID No. 13.
5. 5. A recombinant gene expression cassette comprising the recombinant nucleic acid molecule of claim 4.
6. 6. A recombinant vector comprising the recombinant nucleic acid molecule of claim 4 or the recombinant gene expression cassette of claim 5.
7. 7. A recombinant host cell comprising the recombinant nucleic acid molecule of claim 4, or the recombinant gene expression cassette of claim 5, or the recombinant vector of claim 6.
8. 8. An immunogenic or pharmaceutical composition comprising one or more components selected from the group consisting of the fusion protein of any one of claims 1-3, the recombinant nucleic acid molecule of claim 4, the recombinant gene expression cassette of claim 5, the recombinant vector of claim 6, and the recombinant host cell of claim 7.
9. 9. A recombinant vaccine comprising one or more components selected from the group consisting of the fusion protein of any one of claims 1 to 3, the recombinant nucleic acid molecule of claim 4, the recombinant gene expression cassette of claim 5, the recombinant vector of claim 6, the recombinant host cell of claim 7, the immunogenic composition of claim 8, and the pharmaceutical composition.
10. 10. Use of the fusion protein of any one of claims 1-3, the recombinant nucleic acid molecule of claim 4, the recombinant gene expression cassette of claim 5, the recombinant vector of claim 6, the recombinant host cell of claim 7, the immunogenic composition or pharmaceutical composition of claim 8 or the recombinant vaccine of claim 9 in the manufacture of a medicament for the prevention and/or treatment of a disease caused by pathogenic bacteria of the family pasteurellaceae, characterized in that the pathogenic bacteria of the family pasteurellaceae are selected from any one of the group consisting of pasteurella multocida (Pasteurella multocida), haemophilus parasuis (GLAESSERELLA PARASUIS), mannheimia haemolytica (MANNHEIMIA HAEMOLYTICA), haemophilus influenzae (Haemophilus influenzae) and haemophilus paragallinarum (Avibacterium paragallinarum).
11. 11. The use according to claim 10, wherein the disease is selected from any one of the following: fowl cholera, swine plague, bovine hemorrhagic septicemia, rabbit rhinitis, cellulitis, respiratory tract infection or bacteremia caused by pasteurella multocida; Haemophilus parasuis caused by haemophilus parasuis, multiple serositis, arthritis or meningitis; bovine heat of transport, mastitis or caprine pneumonia caused by mannheimia haemolytica; meningitis, epiglottitis, bacteremia, septicemia, suppurative arthritis, osteomyelitis, pericarditis, otitis media, sinusitis, bronchitis or pneumonia caused by haemophilus influenzae; infectious rhinitis in chicken caused by haemophilus parasuis.

Description

Fusion protein and nucleic acid vaccine for preventing and treating various pathogenic Pasteurella bacterial infections and application thereof Technical Field The invention relates to the technical field of biological medicine, in particular to the technical field of immune medicines, and in particular relates to a fusion protein and a nucleic acid vaccine for preventing and treating various pathogenic Pasteurella bacterial infections and application thereof. Background Pasteurella (Pasteurellaceae) is a class of gram-negative facultative anaerobic Brevibacterium, often parasitic to the upper respiratory tract and oral mucosa of a variety of domestic and wild animals, where a variety of strains have pathogenic potential. Pathogenic Pasteurella, such as Pasteurella multocida (Pasteurella multocida), can cause hemorrhagic septicemia, fowl cholera, respiratory tract infections in animals, and can also be transmitted to humans through scratch, bite or intimate contact, causing local infections, bacteremia and even systemic infections, which are typical zoonotic pathogens. Similar to many extracellular parasitic bacteria, pasteurella, after colonization in the host, resists phagocytosis by the capsule and secretes various toxins and adhesion factors that exacerbate tissue injury and inflammatory response. Clinically, the traditional treatment of the infection is highly dependent on antibiotics, but due to the wide use of antibiotics in livestock breeding and even abuse of antibiotics, drug-resistant strains are continuously appeared, so that the treatment difficulty of partial cases is increased, the course of the disease is prolonged, and even the death risk is increased. The consequences of infection are more severe especially in immunocompromised and elderly populations. Vaccination is considered to be the most cost effective way to control Pasteurella infection. At present, the vaccine against the Pasteurella is mainly a traditional inactivated whole-bacterium vaccine, a capsular polysaccharide vaccine or a subunit toxin vaccine, such as a type A, a type B, a type D and other different capsular serotype vaccines against the Pasteurella multocida. However, such vaccines have the problems of strong serotype specificity and narrow protective range, and it is difficult to provide cross-immunity protection for different serotypes and different types of pasteurella. Some researchers have tried to develop capsular polysaccharide conjugate vaccines or fusion toxin protein vaccines to widen the immune coverage, for example, patent "Haemophilus influenzae type b conjugate vaccine and preparation method thereof" (publication No. CN 103007276A) discloses a technical scheme of covalently binding the capsular polysaccharide of Haemophilus influenzae type b with tetanus toxoid, and some researches focus on toxin proteins (such as PMT, hsf and the like) as immunogens to block key pathogenic mechanisms. However, the existing vaccine has a plurality of limitations that firstly, the vaccine based on the capsule is difficult to cover all epidemic serotypes, and is easy to cause immune escape and serotype replacement, secondly, the polysaccharide protein combined vaccine has complex process and high cost, is not beneficial to large-scale popularization in animal husbandry, thirdly, animal hosts have various types and different infection behaviors, and a single antigen is difficult to induce balanced and effective immune response in all hosts. With the progress of high-throughput sequencing and comparative genomics and bioinformatics technologies, reverse vaccinology provides a new path for screening protein antigens with high conservation and good immunogenicity. Through antigen prediction at the whole genome level, protein antigens which are conserved across serotypes can be extracted from huge coding genes of Pasteurella, and the antigens are highly homologous in a plurality of strains, so that the antigens are expected to be used for constructing novel vaccines with broad-spectrum protection potential. Compared with the traditional polysaccharide vaccine or whole-strain inactivated vaccine, the novel vaccine based on the conserved protein antigen has the remarkable advantages of (1) breaking through serotype limitation and realizing cross protection on various pathogenic Pasteurella, (2) being capable of adopting a recombinant protein expression system for large-scale preparation, being relatively simple in process and controllable in cost, and (3) being easy to construct a multi-antigen combined vaccine, covering different pathogenic mechanisms and enhancing the immune effect. In view of the above, it is particularly urgent to develop a novel vaccine with broad-spectrum protection effect, safety and easy production, which is against the current dual challenges of increasingly complex epidemic situation of pathogenic Pasteurella infection and decline of antibiotic curative effect. By utilizing modern technical means such as