A representation of a nanoparticle vaccine that contains proteins from many different flu strains. Credit: UW Medicine Institute for Protein Design
Scientists at UW Medicine and NIH have created experimental flu vaccines that stimulate broad immunity in animal testing.
The researchers developed experimental flu vaccines that protect animals from a wide variety of seasonal and pandemic flu strains. The vaccine product is currently undergoing clinical trials. If proven safe and effective, these next generation influenza vaccines can replace current seasonal options, providing protection against many other strains that current vaccines do not adequately cover.
A study detailing how the new flu vaccines were made and how they protect mice, ferrets and non-human primates appears in the March 24, 2021 issue of the magazine. Nature. This work was led by researchers from the Washington University School of Medicine and Vaccine
Research Center is part of the National Institute of Allergy and Infectious Diseases of the National Institutes of Health.
The flu virus causes about 290,000-650,000 deaths each year. Available flu vaccines, which need to be taken seasonally, often do not protect against many circulating strains of influenza that cause disease, and the threat of another flu pandemic is looming.
Neil King, from the Department of Biochemistry at the University of Washington School of Medicine, and research by the UW Medicine Institute for Protein Design describes the development of an experimental nanoparticle vaccine against a variety of seasonal and pandemic influenza strains. Credit: Randy Carnell / UW Medicine
“Most flu vaccines available today are quadrivalent, which means they are made from four different strains of flu. Each year, the World Health Organization makes a bet on which four strains will be most prevalent, but these predictions can vary significantly in its precision. That’s why we often end up with ‘incompatible’ flu vaccines that are still useful, but only partially effective, ”said lead author Daniel Ellis, a research scientist in Neil King’s laboratory. King is an assistant professor of biochemistry at the UW School of Medicine and a researcher at the Institute for Protein Design at UW Medicine.
To create improved flu vaccines, the team attached hemagglutinin proteins from four different flu viruses to personalized protein nanoparticles. This approach allowed an unprecedented level of control over the molecular configuration of the resulting vaccine and produced an improved immune response compared to conventional flu vaccines. The new nanoparticle vaccines, which contain the same four hemagglutinin proteins from commercially available quadrivalent influenza vaccines, elicited neutralizing antibody responses to vaccine-like strains that were equivalent or superior to commercial vaccines in mice, ferrets and non-human primates. Nanoparticle vaccines – but not commercial vaccines – also induced protective antibody responses to viruses not contained in the vaccine formulation. This includes the H5N1 and H7N9 avian influenza viruses, which are considered to be pandemic threats.
“The responses that our vaccine gives against viruses corresponding to the strain are really strong, and the additional coverage we’ve seen against incompatible strains can reduce the risk of a strong flu season,” said Ellis.
Reference: March 24, 2021, Nature.
DOI: 10.1038 / s41586-021-03365-x