The Search for Single-Domain Antibodies Interacting with the Receptor-Binding Domain of SARS-CoV-2 Surface Protein.

We performed a search for nanoantibodies that specifically interact with the receptor-binding domain (RBD) of the SARS-CoV-2 surface protein. The specificity of single-domain antibodies from the blood sera of a llama immunized with RBD of SARS-CoV-2 surface protein S (variant B.1.1.7 (Alpha)) was analyzed by ELISA. Recombinant trimers of the SARS-CoV-2 spike protein were used as antigens. In this work, a set of single-domain antibodies was obtained that specifically bind to the RBD of the SARS-CoV-2 virus.