Researchers at the Francis Crick Institute in London have discovered that a specific region of the spike protein of Sars-CoV-2 – the virus that causes Covid-19 – is a good target for a pan-coronavirus vaccine that could offer protection against all Covid-19 variants and common colds. Developing a vaccine that protects against a number of different coronaviruses is a huge challenge, they said, because this family of viruses has many key differences, often mutates and generally provides insufficient protection against reinfection. This is why people can catch the common cold repeatedly and why it is possible to be infected multiple times with different variants of Sars-CoV-2. A universal coronavirus vaccine should activate antibodies that recognize and neutralize a range of coronaviruses, scientists said, preventing the virus from entering host cells and replicating. In the new study, the researchers investigated whether antibodies targeting the “S2 subunit” of the Sars-CoV-2 spike protein also neutralized other coronaviruses. The researchers found that after inoculating mice with Sars-CoV-2 S2, the mice developed antibodies capable of neutralizing a number of other animal and human coronaviruses. They included the common cold coronavirus HCoV-OC43, the original strain of Sars-CoV-2, the D614G mutant that dominated the first wave, Alpha, Beta, Delta, the original Omicron, and two bat coronaviruses. The findings are published in the journal Science Translational Medicine. “The S2 region of the spike protein is a promising target for a potential pancoronavirus vaccine because this region is much more similar in different coronaviruses than the S1 region,” said study co-first author Kevin Ng of Francis Crick. Institute. “It’s less prone to mutations, and so a vaccine that targets that region should be more potent.” Until now, the S2 region of the spike protein had been overlooked as a potential basis for vaccination, the researchers said. George Kasiotis, corresponding author and team leader at the Francis Crick Institute, said: “The expectation for a vaccine targeting the S2 region is that it could provide some protection against all 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. “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.” The researchers will continue their work by studying the potential of a pan-coronavirus targeting the S2 region of the spike protein and how it could be integrated with currently licensed vaccines. Subscribe to First Edition, our free daily newsletter – every morning at 7am. BST Nikhil Faulkner, a co-first author, also of the Francis Crick Institute, said: “While a potential S2 vaccine would not prevent people from becoming infected, the idea is that it would prime their immune system to respond to a future coronavirus infection . “This would hopefully provide enough protection for them to survive an initial infection during which they could develop further virus-specific immunity.” Professor Penny Ward, visiting professor of pharmaceutical medicine at King’s College London, who was not involved in the study, said a global coronavirus vaccine “could solve the problem of endless new waves of disease caused by variants with reduced susceptibility to vaccines”.
