Novel influenza vaccine M2SR protects against drifted H1N1 and H3N2 influenza virus challenge in ferrets with pre-existing immunity.

Novel influenza vaccine M2SR protects against drifted H1N1 and H3N2 influenza virus challenge in ferrets with pre-existing immunity. Vaccine. 2018 Jul 12;: Authors: Hatta Y, Boltz D, Sarawar S, Kawaoka Y, Neumann G, Bilsel P Abstract Current influenza vaccines do not provide effective protection against heterologous influenza viruses. The ability of the novel M2SR influenza vaccine to protect against drifted influenza viruses was evaluated in naïve ferrets and in ferrets with pre-existing immunity to influenza. In naïve ferrets, M2SR provided similar protection against drifted challenge viruses as the comparator vaccine, FluMist®. However, in ferrets with pre-existing immunity, M2SR provided superior protection than FluMist in two model systems. In the first model, ferrets were infected with influenza A H1N1pdm and influenza B viruses to mimic the diverse influenza exposure in humans. The pre-infected ferrets, seropositive to H1N1pdm and influenza B but seronegative to H3N2, were then vaccinated with H3N2 M2SR or monovalent H3N2 FluMist virus (A/Brisbane/10/2007, clade 1) and challenged 6 weeks later with a drifted H3N2 virus (clade 3C.2a). Antibody titers to Brisbane/10/2007 were higher in M2SR vaccinated ferrets than in FluMist vaccinated ferrets in the pre-infected ferrets whereas the opposite was observed in naïve ferrets. After challenge with drifted H3N2 virus, M2SR provided superior protection than FluMist monovalent vac...
Source: Vaccine - Category: Allergy & Immunology Authors: Tags: Vaccine Source Type: research