Zeyuan Wang1, Zhuotian Li1, Xiang Su1, Yiyi Qiao2, Weifeng Fan2, Haibin Li2, Baolan Shi3, Tao Qin2, Sujuan Chen2, Daxin Peng4, Xiufan Liu2. 1. College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, PR China. 2. College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, PR China; Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou, Jiangsu, PR China; Jiangsu Research Centre of Engineering and Technology for Prevention and Control of Poultry Disease, Yangzhou, Jiangsu, PR China. 3. Sinopharm Yangzhou Vac Biological Engineering Co. LtD, Yangzhou, Jiangsu 225009, PR China. 4. College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, PR China; Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonoses, Yangzhou, Jiangsu, PR China; Jiangsu Research Centre of Engineering and Technology for Prevention and Control of Poultry Disease, Yangzhou, Jiangsu, PR China; The International Joint Laboratory for Cooperation in Agriculture and Agricultural Product Safety, Ministry of Education, Yangzhou, Jiangsu 225009, PR China. Electronic address: pengdx@yzu.edu.cn.
Abstract
BACKGROUND: Antigenic drift of H9N2 low pathogenic avian influenza viruses (AIV) may result in vaccination failure in the poultry industry and thus a cross-protective vaccine against H9N2 AIV is highly desirable. METHODS: A series of H9N2 recombinant viruses with the internal genes of A/Puerto Rico/8/34 (H1N1, PR8) were generated, based on the compatibility between HA and NA, the effect of HA deglycosylation, and protective antigenic epitopes in HA. After evaluation of their biological and immunological characteristics, three recombinant AIVs with the internal genes of the Y280-like strain SN were selected for protective efficacy studies. RESULTS: The recombinant viruses rHASNNA3, rHASN-△200, rHASN-△287, and rHASN-R92G-E93K displayed good cross reactivity and induced higher neutralization antibody titers against both SN and the F98-like strain YZ4. Furthermore, those recombinant viruses had a higher EID50 in chicken embryos after the replacement of internal-gene backbone from PR8 to SN. The rSNHA-△200 induced better protection in immunized chickens against challenge of homologous and heterologous H9N2 avian influenza viruses when compared with the wild type strain. CONCLUSION: The recombinant virus rSNHA-△200 can be used as a potential broad-spectrum vaccine against H9N2 avian influenza.
BACKGROUND: Antigenic drift of H9N2 low pathogenic avian influenza viruses (AIV) may result in vaccination failure in the poultry industry and thus a cross-protective vaccine against H9N2 AIV is highly desirable. METHODS: A series of H9N2 recombinant viruses with the internal genes of A/Puerto Rico/8/34 (H1N1, PR8) were generated, based on the compatibility between HA and NA, the effect of HA deglycosylation, and protective antigenic epitopes in HA. After evaluation of their biological and immunological characteristics, three recombinant AIVs with the internal genes of the Y280-like strain SN were selected for protective efficacy studies. RESULTS: The recombinant viruses rHASNNA3, rHASN-△200, rHASN-△287, and rHASN-R92G-E93K displayed good cross reactivity and induced higher neutralization antibody titers against both SN and the F98-like strain YZ4. Furthermore, those recombinant viruses had a higher EID50 in chicken embryos after the replacement of internal-gene backbone from PR8 to SN. The rSNHA-△200 induced better protection in immunized chickens against challenge of homologous and heterologous H9N2 avian influenza viruses when compared with the wild type strain. CONCLUSION: The recombinant virus rSNHA-△200 can be used as a potential broad-spectrum vaccine against H9N2 avian influenza.