Single COVID, Cold Vaccine

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.

SARS-CoV-2 Spike Protein

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.

“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 coronaviruses than the S1 area. It is less subject to mutations, and so a vaccine targeted at this area should be more robust,” Kevin Ng, a doctoral student in the Retroviral Immunology Laboratory at the Crick.

The S2 area of the spike protein has, until recently, been overlooked as providing a basis for vaccination. This is because certain critical targets in the S2 area are only revealed after the virus has bound to a cell, a process mediated by the S1 area.

As a result, there may be a narrower window of opportunity for S2 antibodies to neutralize the virus than for antibodies that target the S1 area.

“There’s a lot of research still to do as we continue to test S2 antibodies against different coronaviruses and look for the most appropriate route to design and test a potential vaccine,” said George Kassiotis, corresponding author and principal group leader at the Crick.

Source: IANS