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A new study by the Institute for Biomedical Sciences, Georgia State University, has shown that a novel nanoparticle-vaccine that combines two major influenza proteins can effectively provide mice with broad and long-lasting protection against influenza viruses, suggesting it has hope to be a universal influenza vaccine for humans. This finding is published in the journal Advanced Healthcare Materials.
The influenza virus proteins, matrix protein 2 extracellular domain (M2e) and neuraminidase (NA) made up the double-layered nano-vaccine. Before being exposed to influenza viruses, mice were immunized with nano-vaccines and protected against six different virus strains. The result has shown that such unique combination of vaccines has the possibility to be used as universal influenza vaccines or as an ingredient in such vaccines.
Ye Wang, Ph.D., the first author of the study working in Dr. Bao-Zhong Wang’s lab in the Institute for Biomedical Sciences, expressed that this combination of nanoparticle antigens provides powerful cross-protection for mice, and it protects mice from different strains of influenza virus. He said each season there are different strains of influenza virus to affect people, and hope this nanoparticle vaccine can protect humans from different strains of the flu virus by using this method.
Influenza is an infectious respiratory disease caused by influenza viruses, which is the main cause of death from infection. Seasonal influenza vaccines are not enough to prevent influenza outbreaks, so the development of universal influenza vaccines is an ideal strategy to address the threat to public health from influenza and pandemics. The universal influenza vaccine will eliminate the need for vaccination in each season and provide universal protection against all influenza strains.
The influenza virus protein M2e has been found in all influenza virus strains, each with a very similar version, and the protein mutates very slowly over time. The NA protein is found on the surface of influenza virus, and its mutation is much slower than that of other influenza proteins. This double-layered nanoparticle vaccine has M2e as the core and NA covering the surface.
In this study, mice received the nanoparticle vaccine through intramuscular injection and were exposed to one of six influenza virus strains. Facts have proved that the vaccine has long-lasting immune protection, and even four months after immunization, it has not changed against virus attacks.
Co-author of the study, Gilbert Gonzalez, laboratory manager of Dr. Bao-Zhong Wang’s laboratory at the Institute for Biomedical Sciences believes that it is critical to note that many influenza vaccines have not targeted NA before, which has become a more and more important antigen in influenza vaccine research. In the past, because hemagglutinin (HA) dominated, NA has been ignored and underestimated. When people are infected with influenza, the body will react to HA. But the HA protein mutates very rapidly, that’s why scientists must change seasonal influenza vaccines every year. People may be infected with the flu this year and be immune to this specific HA protein, but by the next flu season, the HA protein will change rapidly and people will no longer be protected. Next, the researchers expressed that they would plan to inoculate this double-layered nano-vaccine onto a microneedle patch for skin vaccination.
Reference:
Wang, Y., Deng, L., Gonzalez, G. X., Luthra, L., Dong, C., Ma, Y., … & Wang, B. Z. (2020). Double‐Layered M2e‐NA Protein Nanoparticle Immunization Induces Broad Cross‐Protection against Different Influenza Viruses in Mice. Advanced healthcare materials, 9(2), 1901176.