Researchers have identified that in humans a pan-variant neutralising antibody, called S2X324, whose neutralizing potency was largely unaffected by any of the Omicron strains of the coronavirus, according to a study.
The scientists said that this monoclonal antibody prevents binding to the receptor on host cells that the pandemic coronavirus usually commandeers. They also suggested that combining this antibody with others in a cocktail might reduce the chances of the virus becoming antibody treatment resistant.
Researchers team from University of Washington and Howard Hughes Medical Institute, and Humabs BioMed SA of Vir Biotechnology in Switzerland have looked at several aspects of the effects of exposure to earlier forms of the SARS-CoV-2 spike antigen – or immune-provoking protein — on the immune system’s reaction to the Omicron variants.
The findings have been published in the journal Science.
Omicron variants of the SARS-CoV-2 virus which was at the end of 2021 and have marked genetic differences from the ancestral SARS-CoV-2. The many, distinct mutations in their infection machinery have enabled them to escape from antibodies elicited from the original series of vaccines, from a history of infection, or from both of those two immune-system training events.
Past studies from the same team, according to the study, have noted that the BA.1 Omicron variant emerged as a “major antigenic shift due to the unprecedented magnitude of immune evasion associated with this variant of concern”.
They explained that mutations in two of the main antibody targets in the virus explain why there is a markedly reduced antibody neutralizing ability against these variants, especially in people who have not received booster doses.
“As a result, an increasing number of reinfections are occurring,” the scientists wrote in their paper, “even though these cases tend to be milder than in infections of immunologically naïve individuals”.