A novel subunit vaccine based on Fiber1/2 knob domain provides full protection against fowl adenovirus serotype 4 and induces stronger immune responses than a Fiber2 subunit vaccine.
Poult Sci
; 103(8): 103888, 2024 Aug.
Article
em En
| MEDLINE
| ID: mdl-38851180
ABSTRACT
Outbreaks of hepatitis-hydropericardium syndrome (HHS) caused by fowl adenovirus serotype 4 (FAdV-4) have resulted in huge economic losses to the poultry industry in China since 2015. However, commercially available vaccines against the FAdV-4 infection remain scarce. In our study, subunit vaccine candidates derived from the bacterially expressed recombinant Fiber1 knob domain and Fiber2 knob domain fusion protein (termed as Fiber1/2 knob subunit vaccine) and Fiber2 protein (termed as Fiber2 subunit vaccine) of the FAdV-4 SDSX strain were developed. Immunogenicity evaluation showed that the Fiber1/2 knob subunit vaccine induced the production of antibodies at 7 d postvaccination (dpv), earlier than the Fiber2 subunit vaccine. Moreover, the neutralizing antibody level of the Fiber1/2 subunit vaccine group was higher than the Fiber2 subunit vaccine group, showing significant differences at 14, 21, and 28 dpv. Immune protection test results revealed that both Fiber1/2 knob subunit and Fiber2 subunit vaccines could protect chickens from death against FAdV-4 challenge, although the weight of chickens in the Fiber1/2 knob subunit vaccine group decreased less. Furthermore, analysis of plasma Glutamic oxaloacetic transaminase (AST) and blood glutamic pyruvic transaminase (ALT) levels suggested that the Fiber1/2 subunit vaccine can significantly inhibit liver damage caused by FAdV-4 infection and is more effective in blocking the pathogenicity of FAdV-4 in target organs. In addition, the Fiber1/2 knob subunit vaccine further reduced the viral load in different tissues and virus shedding in chickens than the Fiber2 subunit vaccine. Overall, the Fiber1/2 knob subunit vaccine was more effective than the Fiber2 subunit vaccine. These findings lay the foundation for the development of more effective FAdV-4 subunit vaccines.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Doenças das Aves Domésticas
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Galinhas
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Infecções por Adenoviridae
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Aviadenovirus
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Vacinas de Subunidades Antigênicas
Limite:
Animals
Idioma:
En
Revista:
Poult Sci
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
China