In new research, comprising two studies led by an international team show how the virus can evolve distinctly in different cell types, and adapt its immunity, in the same infected host.
The team sought to investigate the function of a tailor-made pocket in the SARS-CoV-2 spike protein in the infection cycle of the virus. The pocket, discovered by the Bristol team in an earlier breakthrough, played an essential role in viral infectivity.
“An incessant series of variants have completely replaced the original virus by now, with Omicron and Omicron 2 dominating worldwide,” said Professor Imre Berger.
They analyzed an early variant discovered in Bristol, BrisDelta. It had changed its shape from the original virus, but the pocket we had discovered was there, unaltered.
Intriguingly, BrisDelta presents as a small subpopulation in the samples taken from patients but appears to infect certain cell-types better than the virus that dominated the first wave of infections.
The study results showed that one can have several different virus variants in one’s body.
Some of these variants may use kidney or spleen cells as their niche to hide, while the body is busy defending against the dominant virus type. This could make it difficult for the infected patients to get rid of SARS-CoV-2 entirely.
Then the team applied cutting-edge synthetic biology techniques, state-of-the-art imaging, and cloud computing to decipher viral mechanisms at work.
To understand the function of the pocket, the scientists built synthetic SARS-CoV-2 virions in the test tube, that are mimics of the virus but have a major advantage in that they are safe, as they do not multiply in human cells.
Using these artificial virions, they were able to study the exact mechanism of the pocket in viral infection. They demonstrated that upon binding of fatty acid, the spike protein decorating the virions changed their shape.
This switching shape could be a mechanism to avoid detection by the host and strong immune response for a longer period and increase total infection efficiency.
Intriguingly, the same feature also provides us with a unique opportunity to defeat the virus, exactly because it is so conserved with a tailormade antiviral molecule that blocks the pocket.
Source: Medindia
