A lab technician collects blood sample for test at a pathology lab in New Delhi during the COVID-19 pandemic. Credit: Mohd Zakir/Hindustan Times via Getty Images
An antibody isolated from people in India who recovered from COVID-19 can broadly neutralize SARS-CoV-2 variants, including Omicron sub-lineages1.
The antibody locks the viral spike protein, preventing its interaction with a specific host cell receptor, which stops the viruses from entering host cells.
This property of the antibody could potentially be used to develop antibody-based therapies for COVID-19, says a team at the ICGEB-Emory Vaccine Centre, International Center for Genetic Engineering and Biotechnology in New Delhi.
Omicron and its sub-lineages have shown the ability to evade natural and vaccine-generated immunity. The variants also pose a threat to unvaccinated adults and children with weak immune systems.
The scientists, led by Anmol Chandele and Kaja Murali-Krishna, identified 92 SARS-CoV-2-specific monoclonal antibodies by screening single memory B cells from five individuals who had recovered from COVID-19.
The team, which included Sanjeev Kumar and Amit Sharma at the ICGEB and researchers at Emory University in Atlanta, USA, narrowed their search to the most potent antibody called 002-S21F2. It bound to spike proteins from SARS-CoV-2 variants – Wuhan, Alpha, Beta, Gamma, Delta and Omicron – with similar affinities, and neutralized live viruses.
Analysis revealed that the antibody binds to the outer face of the receptor-binding domain of the spike protein. The researchers say that such a binding site could form the basis for designing an effective vaccine.
