A specific area of the SARS-CoV-2 spike protein could be a promising target for a pan-coronavirus vaccine that could offer some protection against new virus variants, and common colds, and help prepare for future pandemics, according to a team of scientists in the UK. Developing a vaccine that provides protection against a number of different coronaviruses is a challenge because this family of viruses has many key differences, frequently mutates, and generally induces incomplete protection against reinfection. This is why people can suffer repeatedly from common colds, and also be infected multiple times with different variants of SARS- CoV-2. A pan-coronavirus vaccine would need to trigger antibodies that recognize and neutralize a range of coronaviruses, stopping the virus from entering host cells and replicating, said the team at the Francis Crick Institute. In their study, published in Science Translational Medicine, they investigated whether antibodies that target the S2 subunit of SARS-CoV-2’s spike protein also neutralize other coronaviruses.
This specific area of the spike protein tethers it to the virus membrane and allows the virus to fuse with the membrane of a host cell. They found that after vaccinating mice with SARS-CoV-2 S2, the mice created antibodies that were able to neutralize a number of other animal and human coronaviruses, including the seasonal ‘common cold’ coronavirus HCoV-OC43, the original strain of SARS-CoV-2, the D614G mutant that dominated in the first wave, Alpha, Beta, Delta, the original Omicron, and two bat coronaviruses. “The S2 area of the spike protein is a promising target for a potential pan-coronavirus vaccine because this area is much more similar across different coro- naviruses than the S1 area.