The universal flu vaccine, one of the great challenges of medicine, achieved its first milestone when it was successfully tested in mice. Researchers at the University of Pennsylvania, United States, developed a universal vaccine candidate that uses mRNA technology. The team led by virologist Claudia Arévalo, opted for technology present in Pzifer and Moderna vaccines against COVID-19 and the results are promising.
The researchers based their work on messenger RNA (mRNA) technology, which introduces the guidelines for kickstarting the immune system and preparing for infection. In this case, Arévalo and company developed a nucleoside-modified mRNA lipid nanoparticle vaccine that encodes hemagglutinin antigens of all 20 influenza virus subtypes.
Hemagglutinin is a protein present on the surface of the influenza virus and plays an important role in infections. There are 18 different versions of hemagglutinin and one end of it has a very high mutation rate. It is because of that the idea of a universal vaccine seemed impossibleHowever, the researchers took a different path.
A vaccine to control all variants of the flu
The scientists’ work focused on introducing the instructions for our cells to make hemagglutinin. The result was a vaccine against 20 subtypes A and B of the virus that would even protect against variants present in birds and other mammals. According to the publication in Nature, the first tests in mice offered positive results.
Subsequently, the researchers infected several mice with two variants of influenza A, one very similar to the H1N1 virus. In the most common subtype, all vaccinated rodents survived, while with the rarer variety, only 80% recovered after one week. The vaccine with RNA technology was effective to protect against complications and variants of the virus.
According to Adolfo García-Sastre, director of the Institute for Global Health and Emerging Pathogens at Mount Sinai Hospital in New York, this vaccine could protect us against flu viruses with pandemic potential. Although the studies are promising, clinical trials in humans are yet to be carried out to guarantee its potential.
Claudia Arévalo, who now works at Pfizer, mentioned that developing the vaccine using the traditional model of other vaccines would be impossible. For Juan Ortín, a researcher at the National Center for Biotechnology, Influenza can be defined as a constant disease caused by an ever-changing virus..
Researchers classify influenza viruses based on two proteins on their surface: hemagglutinin (H) and neuraminidase (N). Currently, 18 H and 11 N glycoprotein variants have been identified. Combinations of hemagglutinin and neuraminidase give rise to all the influenza subtypes that lurk every year.
Arevalo and his team believe that their vaccine has potential, although more research work is required to consider it successful in the future.