Efforts to design a so-called “pan-coronavirus vaccine” have so far proved largely fruitless. This type of jab should remain effective against frequent mutations. But scientists at the Francis Crick Institute now believe they have identified a genetic feature of Sars-CoV-2 that appears to be “similar” to a number of coronaviruses and is less prone to mutation, making it a potential target for a pan-coronavirus, or universal , vaccine. In their study, published today in Science Translational Medicine, the researchers investigated whether antibodies trained to target the S2 subunit of the Sars-CoV-2 spike protein can also neutralize other coronaviruses. The S2 subunit binds the spike protein to the viral membrane and allows the virus to fuse with the membrane of a host cell. When used in mice, the scientists’ vaccine produced antibodies that targeted the S2 subunit and were able to neutralize a variety of coronaviruses, including the seasonal “common cold” coronavirus HCoV-0C43, the parent strain of Sars-CoV-2. Alpha, Beta, Delta, the original Omicron variant and two bat coronaviruses. Kevin Ng, one of the study’s co-authors and a PhD student in the Retrovirus Laboratory at the Francis Crick Institute, said the S2 region of the spike protein was a “promising target for a potential coronavirus panic vaccine because this region is much bigger. similar in different coronaviruses from the S1 region. It is less subject to mutation, and so a vaccine targeting this region should be more potent.” George Kassiotis, head of the team at the Francis Crick Institute, said a vaccine specific for the S2 subunit could potentially offer protection against current and future coronaviruses. “This differs from vaccines that target the more variable S1 region, which, while effective against the respective variant in which they are designed, are less able to target other variants or a wide range of coronaviruses,” he added. “There is still much research to be done as we continue to test S2 antibodies against different coronaviruses and look for the most appropriate route to design and test a potential vaccine.” An S2-specific vaccine would not necessarily prevent people from becoming infected – as seen with the current range of Covid vaccines – but would seek to “prime” a person’s immune system to “respond to a future coronavirus infection”, they said Investigators. Earlier this year, a chief scientist at the World Health Organization said that “the development of a pan-coronavirus vaccine that can cover the different variants of Sars-CoV-2 and perhaps even go beyond and be effective against other coronaviruses would be the holy grail chalice”. . Soumya Swaminathan told the British Medical Journal: “It seems scientifically quite possible to develop one in the next couple of years – this is partly because of the huge amount of research that has been done on Sars-CoV-2.”
