showed that M8 possesses strong adjuvant proprieties when used alongside VLPs-based influenza vaccines: co-treatment of mice with M8 and VLPs expressing neuraminidase (NA) and hemagglutinin (HA) from H5N1 influenza virus, protected the animals from lethal doses of influenza virus and induced a long-term antibody response compared to the combination of VLPs and other adjuvants (Beljanski et al., 2015). This evidence concerns the gene XK and influenza.