Mono- and quadri-subtype virus-like particles (VLPs) containing H10 subtype elicit protective immunity to H10 influenza in a ferret challenge model

Avian-origin influenza represents a global public health concern. In 2013, the H10N8 virus caused documented human infections for the first time. Currently, there is no approved vaccine against H10 influenza. Recombinant virus-like particles (VLPs) represent a promising vaccine approach. In this study, we evaluated H10 VLPs containing hemagglutinin from H10N8 virus as an experimental vaccine in a ferret challenge model. In addition, we evaluated quadri-subtype VLPs co-localizing H5, H7, H9 and H10 subtypes. Both vaccines elicited serum antibody that reacted with the homologous H10 derived from H10N8 virus and cross-reacted with the heterologous H10N1 virus. Quadri-subtype vaccine also elicited serum antibody to the homologous H5, H7, and H9 antigens and cross-reacted with multiple clades of H5N1 virus. After heterologous challenge with the H10N1 virus, all vaccinated ferrets showed significantly reduced titers of replicating virus in the respiratory tract indicating protective effect of vaccination with either H10 VLPs or with quadri-subtype VLPs.