MONDAY, JUNE 25, 2018

NIAID scientists develop novel approach for flu vaccination

A new approach to immunize against influenza could offer a more potent immune response and broader protection than currently licensed seasonal influenza vaccines, according to a recent study published in Nature.

Scientists with the U.S. National Institute of Allergy and Infectious Diseases tested the novel approach in mice and ferrets. The study found the experimental approach offered an immune response against viral strains the animals had not been immunized against.

The scientists developed an experimental vaccine featuring ferritin, a protein that can self-assemble into microscopic pieces called nanoparticles. The team fused ferritin genetically with hemagglutinin, the protein found on the influenza virus' surface. What resulted was a nanoparticle with eight protruding viral spikes.

The scientists used the new nanoparticle as the basis for the vaccine antigen, creating an experimental vaccine using HA from a 1999 strain of H1N1 influenza virus. The first experiment evaluated the vaccine's ability to stimulate an immune response in mice. A single dose, with and without an adjuvant, triggered an immune response comparable to two doses of the current seasonal influenza vaccine. The nanoparticle-based vaccine was active against more strains of H1N1 influenza virus than the currently licensed vaccines.

The team also tested the nanoparticle-based vaccine's ability to protect ferrets from a 2007 strain of H1N1 influenza virus. The virus was not a strain the experimental vaccine was specifically designed to detect, but the immune response of the ferrets still demonstrated significantly lower influenza virus levels than those not immunized.

The novel vaccine concept works by simulating antibodies that attach to the parts of the influenza virus that stay consistent across different strains.

The authors said the vaccine could represent a key step going forward in the attempt to create a universal influenza vaccine to protect against most or all influenza strains without the need for annual vaccinations.