Exposure to new flu strains can stimulate production of antibodies against older versions of the virus, researchers have found. The work suggests how to make longer-lasting vaccines with broader flu-fighting capabilities.
Scientists had suspected that the immune system could draw on its prior experience to craft potent protection against future viruses. But there was no evidence before the new work, says Patrick Wilson, an immunologist at the University of Chicago.
Peter Palese of the Icahn School of Medicine at Mount Sinai in New York City reports August 14 in Science Translational Medicine that he and his colleagues measured antibodies in blood samples drawn from 40 participants in the Framingham Heart Study. The people were born between 1917 and 1952 and lived through the flu pandemics that struck in 1957, 1968 and 1977. The participants volunteered blood samples at five-year intervals between 1987 and 2008.
Palese’s group tracked how antibodies against the three pandemic flu strains changed over time. The researchers also measured levels of antibodies against altered versions of those viruses that were in circulation in 1981 and 1991.