Protective efficacy of an inactivated chimeric H7/H5 avian influenza vaccine against highly pathogenic avian influenza H7N9 and clade 2.3.4.4 H5 viruses

• Published in: Veterinary microbiology 2018-09, Vol.223, p.21-26
• Main Authors: Peng, Cheng, Hou, Guangyu, Li, Jinping, Wang, Suchun, Wang, Yan, Cheng, Shanju, Yu, Xiaohui, Jin, Jihui, Jiang, Wenming
• Format: Article
• Language: English
• Subjects: Animals; Antibodies; Antibodies, Neutralizing - immunology; Antibodies, Viral - immunology; Avian flu; Avian influenza virus; Chickens; Chickens - immunology; Chickens - virology; Chimeric vaccine; Cross Reactions; Growth kinetics; H5N6; H7N9; HEK293 Cells; Hemagglutination inhibition; Hemagglutination Inhibition Tests - veterinary; Hemagglutinins, Viral - genetics; Hemagglutinins, Viral - immunology; Humans; Influenza; Influenza A virus - genetics; Influenza A virus - immunology; Influenza A virus - pathogenicity; Influenza A Virus, H7N9 Subtype - genetics; Influenza A Virus, H7N9 Subtype - immunology; Influenza A Virus, H7N9 Subtype - pathogenicity; Influenza in Birds - prevention & control; Influenza in Birds - virology; Influenza Vaccines - immunology; Kinetics; Poultry; Public health; Vaccines; Vaccines, Inactivated - immunology; Vaccines, Synthetic - immunology; Viruses
• ISSN: 0378-1135; 1873-2542
• DOI: 10.1016/j.vetmic.2018.07.011

•We generated a novel chimeric H7/H5 virus expressing HA1 of the H7N9 virus and HA2 of the H5N6 virus.•The chimeric PR8-H7/H5 induced cross-reactive hemagglutination inhibition antibodies against H7 virus only.•The chimeric PR8-H7/H5 induced serum-neutralizing antibodies against both H7 and H5 viruses.•The chimeric PR8-H7/H5 significantly reduced virus shedding in immunized chickens.•The chimeric PR8-H7/H5 protected chickens against lethal challenge with H7N9 and H5N6 viruses. The highly pathogenic avian influenza (HPAI) H5 and H7N9 viruses pose a serious challenge to public health and the poultry industry in China. In this study, we generated a chimeric H7/H5 recombinant virus that expressed the entire HA1 region of the HPAI A/chicken/Guangdong/RZ/2017(H7N9) virus and the HA2 region of the HPAI A/chicken/Fujian/5/2016(H5N6) viruses. The resulting chimeric PR8-H7/H5 virus exhibited similar growth kinetics as the parental PR8-H5 and PR8-H7 viruses in vitro. The inactivated chimeric PR8-H7/H5 vaccine induced specific, cross-reactive hemagglutination inhibition antibodies against the H7 virus only but induced serum-neutralizing antibodies against both H7 and H5 viruses. Furthermore, the inactivated chimeric PR8-H7/H5 vaccine significantly reduced virus shedding and protected chickens from challenge with the HPAI H5N6 and H7N9 viruses. Our results suggested that the inactivated chimeric PR8-H7/H5 vaccine was effective against HPAI H5 and H7N9 viruses in chickens.