New compound that boosts the effect of vaccines against viruses like flu, HIV and herpes has been discovered by Oxford University scientists.
An 'adjuvant' is a substance added to a vaccine to enhance the immune response and offer better protection against infection.
The Oxford University team, along with Swedish and US colleagues, have shown that a type of polymer called polyethyleneimine (PEI) is a potent adjuvant for test vaccines against HIV, flu and herpes when given in mice.
Mice given a single dose of a flu vaccine including PEI via a nasal droplet were completely protected against a lethal dose of flu. This was a marked improvement over mice given the flu vaccine without an adjuvant or in formulations with other adjuvants.
The Oxford researchers now intend to test the PEI adjuvant in ferrets, a better animal model for studying flu. They also want to understand how long the protection lasts for. It is likely to be a couple of years before a flu vaccine using the adjuvant could be tested in clinical trials in humans, the researchers said.
"Gaining complete protection against flu from just one immunisation is pretty unheard of, even in a study in mice. This gives us confidence that PEI has the potential to be a potent adjuvant for vaccines against viruses like flu or HIV, though there are many steps ahead if it is ever to be used in humans," said Professor Quentin Sattentau of the Dunn School of Pathology at Oxford University, who led the work.
The researchers reported their findings in the journal Nature Biotechnology.