Chicken ISG12(2) attenuates Newcastle disease virus and enhances the efficiency of Newcastle disease vaccine via activating immune pathways

• DOI: 10.1111/tbed.14416
• Publication Date: 2021-12-14T04:25:13Z
• Authors: Haijin Liu; Jianxia Tian; Kejia Lu; Yangyang Li; Zhao Guan; Xuhong Cao; Xiaoqin Li; Zhengwu Chang; Xinglong Wang; Xiao Sa; Zengqi Yang
• Keywords: 0301 basic medicine; 2. Zero hunger; 0303 health sciences; Newcastle Disease; Newcastle disease virus; Viral Vaccines; Vaccines, Attenuated; 3. Good health; 03 medical and health sciences; Animals; Cytokines; Interferons; Chickens; Poultry Diseases

Low virulence and strong immunogenicity are quite important for Newcastle disease virus (NDV) producing Newcastle disease (ND) living-attenuated vaccine. However, immunogenicity of NDV positively correlates to its virulence. Usually, the velogenic NDV induces stronger immune responses of poultry than the lentogenic strain, but virulent NDV poses a risk for chicken. In this study, we identified the chicken interferon (IFN)-stimulated gene 12-2 (ISG12(2)) not only attenuated NDV, but also increased immunogenicity of ND vaccine strain. First, we found that NDV infection or IFNs stimulation induced expression of chicken ISG12(2) that reinforced expression of IFNs. Over-expression or knock-down proved that chicken ISG12(2) inhibited NDV replication. Then, recombinant NDV LaSota strains (rLaSota/Fmut/ISG12(2) and rLaSota/ISG12(2)), expressing ISG12(2), were rescued. Pathogenicity tests showed that ISG12(2) expression attenuated NDV. RNA-seq or RT-qPCR demonstrated that, comparing to rLaSota/Fmut and rLaSota, rLaSota/Fmut/ISG12(2) and rLaSota/ISG12(2) induced hosts to produce cytokines enriching in innate and adaptive immune pathways in vitro and in vivo. Finally, we showed that rLaSota/ISG12(2) vaccination improved immune condition of chicken to quickly respond NDV infection and then enhance protection. These results suggest that chicken ISG12(2) is a potential novel molecular adjuvant to regulate immune responses, which decrease virulence and increase immunogenicity of NDV. The chicken ISG12(2) may contribute to the development of high efficient poultry vaccine.