American scientists have taken several key steps toward developing a near-universal flu vaccine. If further research works out, the vaccine could fight many types of conventional flu, as well as avian influenza, and even the virus that caused the 1918 flu epidemic that killed 50 million people.
Conventional flu strains mutate over time. And every year, well before flu season, scientists have to predict whether new strains will be coming through. Manufacturers base their vaccines on that prediction, which hasn't always been correct. One of the holy grails of immunology is finding some aspect of a virus that doesn't change from strain to strain, so the exact strain is no longer important.
One Key To Fit All Locks
And now, a group of researchers may have done just that. Researchers from Dana-Farber Cancer Institute, Harvard University, the Centers for Disease Control and Prevention, and the Burnham Institute for Medical Research have identified a man-made antibody that recognizes a component of many conventional flu viruses, the 1918 virus and bird flu viruses. The antibody not only recognizes all these virus strains, it neutralizes them by interfering with the virus' ability to infect cells.
One of the discoverers, Dr. Wayne Marasco of Dana-Farber Cancer Institute, says this so-called neutralizing antibody has two potential practical applications. "It lends itself to a therapy that can be used to prevent and treat a broad range of avian and seasonal influenzas," he says. That is, it may be possible to just inject the antibody into people who've just been infected by the bird flu virus or a conventional flu virus.
The second potential application is using the protein the antibody attacks as a vaccine. That protein sits in a pocket just beneath the virus' ever-changing coat. Used as a vaccine, it would train the body to recognize and attack flu viruses.
"I think this is a very important conceptual advance," says Anthony Fauci. He heads the National Institute of Allergy and Infectious Diseases, an organization that partly funded the work. "Now we need to translate it into practicality."
The team of researchers who identified the antibody is already working on animal models to determine how the new information can be used. The research is described in an advance online edition of Nature Structural and Molecular Biology.