(575e) A Virus-Free Fe3O4 Nanoparticle-Based H7N9 Influenza Vaccine

One hundred years has passed since the A/H1N1/1918 influenza caused millions of deaths worldwide. The avian H7N9 influenza virus that emerged in China in 2013 showed a mortality rate approaching 40% with no vaccine available at the time. These influenza outbreaks emphasize the need for rapid manufacture of influenza vaccines for a fast response to epidemic emergencies.

In this contribution, we integrate the use of recombinant technology and nanotechnology to synthetize an influenza nanovaccine candidate. We engineered an Escherichia coli BL21 C41 strain to produce the globular region of the hemagglutinin (HA) from the H7N9 virus in bacteria. The recombinant protein was recovered and purified from the insoluble fraction of the cellular lysate using histidine tag affinity chromatography. The recovered HA protein was attached to Fe₃O₄ paramagnetic nanoparticles functionalized with NH₂ groups through EDC coupling in a microfluidic device. The resulting nanoparticles exhibited anti-HA activity in ELISA experiments when tested against H7N9 polyclonal antibodies. In addition, this nanovaccine candidate triggered a systemic immune response (measured as an increased IgG plasma concentration) and elicited a specific immune response in a chicken model immunized with doses of ~5 µg/kg of body weight (as determined by ELISA).

This class of virus-free vaccine candidates may represent a low-risk and cost-effective alternative for animal and human anti-influenza vaccination.