An attenuated TW-like infectious bronchitis virus strain has potential to become a candidate vaccine and S gene is responsible for its attenuation.
Vet Microbiol
; 254: 109014, 2021 Mar.
Article
em En
| MEDLINE
| ID: mdl-33636510
ABSTRACT
TW-like infectious bronchitis virus (IBV) with high pathogenicity is becoming the predominant IBV type circulating in China. To develop vaccines against TW-like IBV strains and investigate the critical genes associated with their virulence, GD strain was attenuated by 140 serial passages in specific-pathogen-free embryonated eggs and the safety and efficacy of the attenuated GD strain (aGD) were examined. The genome sequences of GD and aGD were also compared and the effects of mutations in the S gene were observed. The results revealed that aGD strain showed no obvious pathogenicity with superior protective efficacy against TW-like and QX-like virulent IBV strains. The genomes of strains aGD and GD shared high similarity (99.87 %) and most of the mutations occurred in S gene. Recombinant IBV strain rGDaGD-S, in which the S gene was replaced with the corresponding regions from aGD, showed decreased pathogenicity compared with its parental strain. In conclusion, attenuated TW-like IBV strain aGD is a potential vaccine candidate and the S gene is responsible for its attenuation. Our research has laid the foundation for future exploration of the attenuating molecular mechanism of IBV.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Vacinas Virais
/
Galinhas
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Vírus da Bronquite Infecciosa
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Fatores de Virulência
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Glicoproteína da Espícula de Coronavírus
Limite:
Animals
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article