Abstract
H7 subtype avian influenza viruses have caused outbreaks in poultry, and even human infection, for decades in both Eurasia and North America. Although effective vaccines offer the best protection against avian influenza viruses, antigenically distinct Eurasian and North American lineage subtype H7 viruses require the development of cross-protective vaccine candidates. In this study, a methodology called computationally optimized broadly reactive antigen (COBRA) was used to develop four consensus H7 antigens (CH7-22, CH7-24, CH7-26, and CH7-28). In vitro experiments confirmed the binding of monoclonal antibodies to the head and stem domains of cell surface-expressed consensus HAs, indicating display of their antigenicity. Immunization with DNA vaccines encoding the four antigens was evaluated in a mouse model. Broadly reactive antibodies against H7 viruses from Eurasian and North American lineages were elicited and detected by binding, inhibition, and neutralizing analyses. Further infection with Eurasian H7N9 and North American H7N3 virus strains confirmed that CH7-22 and CH7-24 conferred the most effective protection against hetero-lethal challenge. Our data showed that the consensus H7 vaccines elicit a broadly reactive, protective response against Eurasian and North American lineage H7 viruses, which are suitable for development against other zoonotic influenza viruses.
Highlights
H7 subtype avian influenza virus has caused outbreaks in poultry, and even human infection, for decades
Eurasian and North American lineage H7 viruses, we investigated the efficacy of the consensus H7 in a mouse model
Yearly updated influenza vaccines consist of inactivated virus with virus with HA from types A(H1N1) pdm09 and A(H3N2), and one/two type B that best match the HA from types A(H1N1) pdm09 and A(H3N2), and one/two type B that best match the predicted predicted circulating strains, but lack cross-protection against novel variants [31]
Summary
H7 subtype avian influenza virus has caused outbreaks in poultry, and even human infection, for decades. Both North American and Eurasian lineages of H7 viruses have been associated with human infection [1], and the global distribution of this subtype has affected poultry in Europe, America, Asia, and Oceania [2]. Human infections have been caused by the poorly pathogenic. Before 2003, less than 20 sporadic cases of human infection with H7 viruses were reported in Europe and America [1]. In 2003, outbreaks of HPAI H7N7 occurred in poultry of several European countries, and 86 poultry workers as well as three of their family members were infected with this subtype in The Netherlands [5]. Almost all infected people developed mild–moderate conjunctivitis and one person died from pneumonia and acute respiratory distress syndrome [5]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
