Researchers have found a way to create a universal flu vaccine

Scientists from the Pirbright Institute and the University of Oxford have taken a significant step towards creating a universal flu vaccine.

Flu vaccines have long been the first line of defense against the disease, but there are significant challenges in using them. These vaccines are designed to target specific strains of the virus, which change rapidly each year. As new strains emerge, the protection provided by these vaccines rapidly wanes, requiring annual vaccine updates and making it more difficult to control potential epidemics and pandemics.

Scientists are therefore seeking to develop flu vaccines that can protect against multiple strains of the virus, eliminating the need for annual updates.

In a new study published in the journal NPJ Vaccines, scientists from Pirbright, in collaboration with the University of Oxford, have obtained new evidence to support the possibility of developing a universal flu vaccine.

Instead of focusing solely on antibodies – proteins that help the immune system fight infections – an approach was taken to activate T cells, another part of the immune system that can recognize and respond to various flu viruses. In addition, the research team explored the use of aerosolized vaccines delivered directly into the respiratory tract, a powerful way to stimulate an immune response.

In the study, the scientists immunized pigs pre-infected with pH1N1 virus with aerosolized viral vaccines (ChAdOx2 and MVA). The results showed that the T-cell response induced by aerosol immunization could provide significant protection.

The pig model is particularly valuable in influenza research because pigs are large natural hosts of influenza A viruses and share many physiological and immunological similarities with humans.

“This study shows how important it is to target the respiratory tract with aerosols to stimulate local immunity and prevent severe disease,” said Professor Elma Tchlian, Head of the Mucosal Immunology Group at Pirbright. “This approach has major implications for both human medicine and veterinary medicine and highlights the potential of respiratory vaccines against influenza and other respiratory pathogens.”

“To our knowledge, this is the first evidence that the T-cell response in the lungs induced by aerosol immunization is protective,” said Dame Sarah Gilbert, professor of vaccinology at the Institute of Pandemic Sciences at the University of Oxford. “We believe these results are a significant achievement and have important implications for the development of next-generation vaccines against influenza and other respiratory pathogens.”

The study is a major immunologic advance and paves the way for the development of next-generation influenza vaccines that can provide broad and durable protection against multiple strains. This achievement could significantly reduce the global burden of influenza and be a critical tool in preventing future epidemics and pandemics.