Farewell to the Annual Flu Vaccine?

The development of the flu vaccine was a feat of pharmaceutical excellence. First produced for US military personnel, the vaccine became available for use by the American public in 1945, and ultimately helped change the trajectory of influenza disease management worldwide – reducing levels of both morbidity and mortality. Though numerous iterations have been developed in the years since, the speedy evolution of the virus has continued to pose a significant challenge for vaccine manufacturers. At the heart of the drug development problem lies hemagglutinin (HA), a surface protein found in flu strains. Its head is often targeted by vaccine products but is prone to rapid mutation, resulting in the need for new vaccines.

A group of scientists from Scripps Research, University of Chicago, and Icahn School of Medicine at Mount Sinai has identified key flu virus antibodies that could expose vulnerabilities in the protein structure of HA and lead to the development of a universal flu vaccine. 

The team characterized over 350 different antibodies found in the blood of people with some form of immunity against the flu. Though many of them were well known, 50 new antibodies capable of binding to HA’s “stalk” – which is less prone to mutation than its head – were identified. To the team’s surprise, many of the newly characterized antibodies are commonly found in the human body, which could help future vaccine development.

“The human immune system already has the ability to make antibodies to this epitope, so it’s just a matter of applying modern protein engineering methods to make a vaccine that can induce those antibodies in sufficient numbers,” Jenna Guthmiller, a postdoctoral fellow at the University of Chicago and co-author of the paper outlining the discovery, said in a statement (2).

The scientists also came to the conclusion that the antibodies they discovered recognized a variety of influenza strains, including the swine-derived H1. And they believe that their findings will help in the development of pertinent “pan-H1 vaccines to prevent the next influenza pandemic.” They are exploring how their findings can be practically applied to the development of new therapeutic interventions.