Scientists say they have the key to the blueprint for a universal flu vaccine, according to a new study in the journal Nature Medicine.
Researchers at the Imperial College London found that certain T-cells protect people from the flu — no matter what strain of the virus hits them. So, targeting the flu from the core instead of stimulating antibodies that protect against specific strains could lead to a one-and-done flu shot.
“We already know how to stimulate the immune system to make CD8 T cells by vaccination,” lead researcher Ajit Lalvani of the National Heart and Lung Institute at Imperial College London told The Independent. “Now that we know these T cells may protect, we can design a vaccine to prevent people getting symptoms and transmitting infection to others. This could curb seasonal flu annually and protect people against future pandemics.”
The researchers came to the conclusion after analyzing the T cells of 300 subjects during the 2009 swine flu pandemic. They noticed that those who didn’t get very sick had more CD8 T cells at the beginning of the pandemic.
“The immune system produces these CD8 T cells in response to usual seasonal flu,” Lalvani said. “Unlike antibodies, they target the core of the virus, which doesn’t change, even in new pandemic strains. The 2009 pandemic provided a unique natural experiment to test whether T cells could recognise, and protect us against, new strains that we haven’t encountered before and to which we lack antibodies.”
It would take about five years before a new flu vaccine would be available, Lalvani said. Current flu vaccines rely on guesstimates of what strains might emerge each season, because the shots and sprays help the immune system create antibodies to prevent infection of specific types of the flu virus.
Between 250,000 and 500,000 people die every year from seasonal flu.