A newly discovered human antibody that can neutralise several subtypes of the influenza A virus in mice is reported in a study published in Nature Communications. The research shows that the antibody has an unusual mode of binding to the virus, potentially supporting the design of more potent vaccines.
Of the three types of influenza, the influenza A virus causes the most severe symptoms and also has the broadest range of host species. Understanding how broadly neutralizing antibodies bind to the influenza virus is important for identification of specific regions that can be targeted for neutralisation.
George Gao and colleagues studied immune cells of patients recovering from the pandemic 2009 swine flu (H1N1) and isolated an antibody with a potent neutralising activity. The antibody was able to bind to several subtypes of influenza virus preventing them from infecting susceptible cells. When given to mice infected with influenza A, it protected them from becoming ill or dying from the H1N1, H3N2, H5N1 subtype viruses and also from the human-infecting H7N9 virus that emerged recently. The breadth of activity of this and other broadly neutralising antibodies suggests that they could be used as novel antivirals against current and future circulating viruses.