Identification of Amino Acids within Nonstructural Proteins 10 and 14 of the Avian Coronavirus Infectious Bronchitis Virus That Result in Attenuation In Vivo and In Ovo.
Identification of Amino Acids within Nonstructural Proteins 10 and 14 of the Avian Coronavirus Infectious Bronchitis Virus That Result in Attenuation In Vivo and In Ovo.
复制标题
导致体内和卵内减毒的禽冠状病毒传染性支气管炎病毒非结构蛋白10和14内氨基酸的鉴定。
DOI：
10.1128/jvi.02059-21
复制
发表时间：
2022-03-23
影响因子：
5.4
通讯作者：
Bickerton E
中科院分区：
文献类型：
--
作者：
Keep S;Stevenson-Leggett P;Dowgier G;Everest H;Freimanis G;Oade M;Hammond JA;Armesto M;Vila R;Bru T;Geerligs H;Britton P;Bickerton E
伽马冠状病毒传染性支气管炎病毒(IBV)是一种高度传染性的全球性病原体，广泛存在于所有类型的禽群中。IBV对家禽的经济损失和福利问题负有责任，对食品安全构成重大风险。目前，IBV疫苗是由强毒IBV野外分离株通过鸡胚化鸡蛋连续传代而成。在这一过程中积累的不同的基因组变异模式意味着，衰减的确切机制尚不清楚，并存在逆转毒力的风险。此外，传代过程使病毒适应于在鸡胚中复制，从而增加了胚胎的致死率。因此，以这种方式生产的疫苗不适合在体内应用。我们已经开发了一个基于致病性IBV毒株M41的反向遗传学系统，以识别可以作为合理减毒靶点的基因。在这个反向遗传学系统的发展过程中，我们鉴定了位于非结构蛋白(NSPS)10、14、15和16的四个氨基酸，它们在体内和卵子中都有衰减。进一步的研究强调了氨基酸的变化，NSP 10中的Pro85Leu和NSP 14中的Val393Leu，在观察到的体内减毒表型中所起的作用。本研究提供的证据表明，NSPS基因突变为IBV合理减毒活疫苗的开发提供了一种有希望的机制，具有在体内应用的潜力。重要信息伽马冠状病毒传染性支气管炎病毒(IBV)是传染性支气管炎的病原体，传染性支气管炎是一种急性、高度传染性、经济上重要的禽类疾病。接种疫苗是使用幼鸡减毒活疫苗和作为蛋鸡增强剂的灭活疫苗的混合物来实现的。减毒活疫苗是通过在胚胎母鸡的鸡蛋中连续传代产生的，这是一个实现减毒但保留免疫原性的经验过程。然而，这些疫苗有恢复毒力的风险，而且它们对胚胎是致命的。在这项研究中，我们在体内和卵子中都鉴定了复制酶基因中的氨基酸，该基因可以使IBV M41株减毒。稳定性分析表明，减毒氨基酸是稳定的，不太可能还原。本研究提供的数据表明，复制酶基因的特异性修饰为IBV减毒活疫苗的开发提供了一个有希望的方向，具有在体内应用的潜力。
The Gammacoronavirus infectious bronchitis virus (IBV) is a highly contagious global pathogen prevalent in all types of poultry flocks. IBV is responsible for economic losses and welfare issues in domestic poultry, resulting in a significant risk to food security. IBV vaccines are currently generated by serial passage of virulent IBV field isolates through embryonated hens’ eggs. The different patterns of genomic variation accumulated during this process means that the exact mechanism of attenuation is unknown and presents a risk of reversion to virulence. Additionally, the passaging process adapts the virus to replicate in chicken embryos, increasing embryo lethality. Vaccines produced in this manner are therefore unsuitable for in ovo application. We have developed a reverse genetics system, based on the pathogenic IBV strain M41, to identify genes which can be targeted for rational attenuation. During the development of this reverse genetics system, we identified four amino acids, located in nonstructural proteins (nsps) 10, 14, 15, and 16, which resulted in attenuation both in vivo and in ovo. Further investigation highlighted a role of amino acid changes, Pro85Leu in nsp 10 and Val393Leu in nsp 14, in the attenuated in vivo phenotype observed. This study provides evidence that mutations in nsps offer a promising mechanism for the development of rationally attenuated live vaccines against IBV, which have the potential for in ovo application. IMPORTANCE The Gammacoronavirus infectious bronchitis virus (IBV) is the etiological agent of infectious bronchitis, an acute, highly contagious, economically important disease of poultry. Vaccination is achieved using a mixture of live attenuated vaccines for young chicks and inactivated vaccines as boosters for laying hens. Live attenuated vaccines are generated through serial passage in embryonated hens’ eggs, an empirical process which achieves attenuation but retains immunogenicity. However, these vaccines have a risk of reversion to virulence, and they are lethal to the embryo. In this study, we identified amino acids in the replicase gene which attenuated IBV strain M41, both in vivo and in ovo. Stability assays indicate that the attenuating amino acids are stable and unlikely to revert. The data in this study provide evidence that specific modifications in the replicase gene offer a promising direction for IBV live attenuated vaccine development, with the potential for in ovo application.
登录
查看更多内容
影响因子：
3.7
作者：
Armesto M;Cavanagh D;Britton P
通讯作者：
Britton P
影响因子：
3.5
作者：
Ferretti, Luca;Tennakoon, Chandana;Ribeca, Paolo
通讯作者：
Ribeca, Paolo
影响因子：
2.7
作者：
COOK, JKA;DARBYSHIRE, JH;PETERS, RW
通讯作者：
PETERS, RW
影响因子：
2.8
作者：
Geerligs, H. J.;Boelm, G. -J.;Kumar, M.
通讯作者：
Kumar, M.
影响因子：
2.8
作者：
Cook, JKA;Orbell, SJ;Huggins, MB
通讯作者：
Huggins, MB