Summary
Influenza A virus (IAV), a deadly
zoonotic pathogen, occasionally cross-species transmission among humans,
swine and avian. The ectodomain of matrix protein 2 (M2e) is highly
conserved in IAV and has been widely concerned in the development of
universal influenza vaccines. Due to low immunogenicity, multi-copy M2e
are usually displayed on the surface of nanoparticles to constitute
universal nanovaccines. Here, we report that the permutation of the M2e
affects the immune effect of the nanovaccine. Three M2e derived from
humans, swine and avian IAV were inserted into the C-terminal of the Cap
protein of porcine circovirus type 2 (PCV2) to form self-assembled
nanovaccine. Immunoprotective effects of different M2e arrangements were
explored in mice. Results showed that the M2e closest to the surface of
nanoparticle induced the most efficient protection against IAV derived
from corresponding species. The results will help in the development of
more effective universal influenza vaccines, especially for specific
species.
Keywords: influenza A virus; porcine circovirus type 2; M2e;
universal; nanovaccine; permutation