Chimeric hemagglutinin vaccine elicits broadly protective CD4 and CD8 T cell responses against multiple influenza strains and subtypes

Significance Pandemic influenza continues to threaten public health across the world. Cross-species transmission of avian H5N1, H7N9, and H10N8 subtypes represent a potential threat to human as the viruses may acquire the ability to pass efficiently from human to human. In order to develop an effective influenza vaccine with protective immunity against a broad range of human and avian influenza viruses, we generated a monoglycosylated consensus cHA (cHAmg ) from human H1N1 and avian H5N1 HAs. After immunization with the monoglycosylated consensus cHA vaccine, mice were found to generate a high level of antibodies with broader cross-reactive neutralizing activities, higher ADCC responses, and more memory CD8+ T cell response. This strategy may facilitate the development of a universal vaccine against influenza viruses.