Universal flu vaccine could prevent pandemics in the future

An article published in Nature Medicine shows that researchers at Imperial College London are very close to developing a universal vaccine against flu. To get to this point, researchers used the 2009 pandemics to find out why some people are resistant to severe illness. Researchers collected blood samples from volunteers who reported having any kind of flu symptom during the swine flu pandemic, and in this way they found that those who were not ill at that time had more CD8 T cells in the blood. CD8 T cells are part of the immune system (with B cells, natural killer cells, macrophages etc. )that destroy viruses.

Based on this discovery, researchers thought that if there was a possibility to stimulate the body to produce more CD8 T cells, the body would be more resistant to infection. Professor Ajit Lalvani from the National Heart and Lung Institute at Imperial College London, who led the study, noted that flu strains continue to emerge and some of these are life threatening. He added that the goal is to create a universal vaccine that is effective against all strains of flu.

It must be said that today’s vaccines contain viruses or components of viruses that stimulate immunity as they cause the body to produce antibodies. When the organism comes into contact with a virus, the antibodies recognize it (in fact , they recognize structures on the surface of the viruses ) and destroy it. But as mentioned Professor Lalvani, there always appear new strains of flu with new structures, which means that vaccines are not effective in all cases.

Previous studies have shown that T cells can protect against flu symptoms but so far there have not been research to prove this hypothesis in humans. In autumn 2009 , the research team of Professor Lalvani recruited 342 staff and students. Participants in the study were collected blood for investigations and received nasal swabs. Every three weeks, they had to fill out a survey about their health and if they had flu symptoms, they had to take the nasal swabs that they received at the beginning of the study and send it to the lab.

Researchers found that those who had severe flu symptoms, had fewer T cells in their blood, and those who caught flu but had no symptoms or had mild symptoms were found to have more T cells. “Our findings suggest that by making the body produce more of this specific type of CD8 T cell, you can protect people against symptomatic illness. This provides the blueprint for developing a universal flu vaccine,” Lalvani said.