A key step to the SARS-CoV-2 infection is the attachment of its Spike receptor-binding domain (S RBD) to the host receptor ACE2. Considerable research has been devoted to the development of neutralizing antibodies. including llama-derived single-chain nanobodies. to target the receptor-binding motif (RBM) and to block ACE2-RBD binding. https://www.roneverhart.com/BB-CLUBHOUSE-JEAN-HELIX/