For the millions of people around the world who suffer each winter from flu, and especially for those with weak immune systems, such as, children, the elderly and pregnant women there is promise of a new “super vaccine.”
Scientists from Switzerland’s Institute for Research in Biomedicine (IRB) just announced that they have isolated and identified a human antibody – F16 – that can knock out all influenza A viruses. Tests in mice showed it was effective. This represents an exciting step forward in the hunt for a universal vaccine.
Currently, in what amounts to little more than a scientific lottery, virologists have to play catch-up as they develop a new flu vaccine cocktail each season to match the often-changing strains of the virus.
F16, could help change all that. “The antibody works not only by neutralizing the virus, which we knew, but also by recruiting killer cells to the virus-infected cells,” said Antonio Lanzavecchia, director of IRB.
By observing the human immune response to the 2009 H1N1 flu pandemic he became convinced that it would be possible to design a vaccine that prevails over mutation. “We found some people with antibodies to multiple viral sub-types.” Antibodies, which are produced by white blood cells, bind to specific target sites inactivating viruses or flagging them for destruction by other immune cells. To test the cross-reactivity of influenza antibodies, the team screened B cells from eight human donors who had been infected with or immunized against different flu strains. After looking at 104,000 B cells, they hit the jackpot!
“Our FI6 antibody is the first one ever found that reacts to all 16 of the influenza A subtypes,” said Lanzavecchia.
“Finding antibodies to all strains of one group was exciting,” says immunologist, Patrick Wilson from the University of Chicago, Illinois, who was not involved with the study, “but getting one to both groups is stunning.”
The F16 antibody is not a vaccine, but it could be an instruction manual for making one. And although the scientists admit that making a new vaccine may take years, they hope that the antibody itself might be used as a treatment in the meantime. So far, tests in animals have shown that when the antibody binds to the virus, it stops it from infecting mammalian cells.
Once tested in a human system, the antibodies should work even better. However, even reducing the viral load by 10% could help stop people getting sick.
SRxA’s Word on Health looks forward to having one less thing to worry about in winter.