New York: An international team of researchers has identified a pan-variant and ultra-potent neutralising antibody that can offset Omicron variants.
Named 'S2X324', its neutralising potency was largely unaffected by any of the Omicron variants tested, said the study published in the journal Science.
The scientists suggested that combining this antibody with others in a cocktail might reduce the chances of the virus becoming antibody-treatment resistant.
The team 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.
Past studies from the same team 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 markedly reduced antibody neutralising ability against these variants, especially in people who have not received booster doses. "As a result, an increasing number of reinfections are occurring," the researchers wrote, "even though these cases tend to be milder than in infections of immunologically naA-ve individuals".
The recent scientific studies in this area have been led by the labs of David Veesler, associate professor of biochemistry at the University of Washington in Seattle and Howard Hughes Medical Institute Investigator, and Davide Corti of Humabs BioMed SA of Vir Biotechnology in Switzerland. The Omicron variants appeared 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.
People who had a breakthrough infection after vaccination also produced neutralising antibodies against these variants in the mucus lining the inside of their noses.
However, people who only received the vaccine did not generate antibodies in their nasal mucosa. "This finding lends support to efforts to develop and evaluate next-generation Covid vaccines that could be delivered intranasally as the nose is generally the site where the virus first enters the body," said the scientists.
The lead authors on the paper are from the Veesler lab, the Corti lab, and Washington University in St. Louis. —IANS