New Universal Flu Vaccine Protects Against Influenza A
Researchers at the Institute of Biomedical Sciences at Georgia State University have developed a universal flu vaccine by genetically linking two parts of the virus that are highly conserved (relatively unchanged over time) – the foreign domain. matrix 2 (M2e) and stalk proteins found in influenza A H3N2 virus.
The findings, published in the journal npj . vaccineshowed that vaccination with the M2e-stalk protein conferred broad protection against different strains and subtypes of influenza virus by vaccine-mediated pervasive immunity in adult and aged mice. .
Scientists have faced obstacles in developing an effective vaccine for the flu virus because the head of the flu virus is constantly changing.
When comparing influenza A viruses H1N1 and H3N2, particular challenges exist in the H3N2 subtypes due to pedunculated mutations in circulating strains and the unstable conformation of stem proteins for H3N2 viruses. . These limitations are difficult to overcome in developing effective H3 stub-based vaccines.
Vaccine efficacy against H3N2 has been low over the past decade, only about 33%, and dropped to 6% during the 2014-2015 flu season. New mutations of the H3N2 variants appear with increased virulence.
In addition, the outbreak of H7N9, another influenza A subtype, raises concerns about potential pandemics. Therefore, developing an effective vaccine to protect against these viruses is a top priority.
“For the first time, the M2e-stalk protein can be easily produced in high yield bacterial cell cultures and is found to be protective against heterozygous and cross-type viruses. heterozygotes (H1N1, H5N1, H9N2, H3N2 and H7N9) at Dr. Sang-Moo Kang, Professor at the Institute, reported similar levels in adult and aged mice.
Kang adds: “These results provide evidence that M2e-stemmed genetic fusion proteins can be produced on a large scale at low cost and developed as a viral vaccine candidate. common influenza A virus among young and old populations”.
The study showed that this new M2e stub protein vaccine induces stem-specific M2e and Immunoglobulin G (IgG) antibodies, which recognize antigenically diverse influenza virus antigens on viral particles and on infected cell surface.
In addition, the vaccine stimulated protective T-cell immunity and effectively eliminated lung influenza virus in mice.