Currently, the incorporation of multiple
epitopes into
vaccines is more desirable than the incorporation of a single
antigen for
universal influenza vaccine development. However,
epitopes induce poor immune responses. Although the use of adjuvants can overcome this obstacle, it may raise new problems. Effective
antigen delivery vehicles that can function as both
antigen carriers and intrinsic adjuvants are highly desired for
vaccine development. Here, we report a biepitope
nanovaccine that provides complete protection in mice against H3N2 virus as well as partial protection against H1N1 virus. This
vaccine (3MCD-f) consists of two conserved
epitopes (matrix
protein 2 ectodomain (M2e) and CDhelix), and these
epitopes were presented on the surface of
ferritin in a sequential tandem format. Subcutaneous immunization with 3MCD-f in the absence of adjuvant induces robust humoral and cellular immune responses. These results provide a proof of concept for the 3MCD-f
nanovaccine that might be an ideal candidate for future
influenza pandemics.