Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.07.27.224089v1?rss=1 Authors: Beasley, M. D., Aracic, S., Gracey, F. M., Kannan, R., Masarati, A., Premaratne, S. R., Udawela, M., Wood, R. E., Jabar, S., Church, N., Le, T.-K., Makris, D., McColl, B. K., Kiefel, B. R. Abstract: Antibodies with high affinity against the receptor binding domain (RBD) of the SARS-CoV-2 S1 ectodomain were identified from screens using the Retained DisplayTM (ReD) platform employing a 1 x 10^11 clone single-chain antibody (scFv) library. Numerous unique scFv clones capable of inhibiting binding of the viral S1 ectodomain to the ACE2 receptor in vitro were characterized. To maximize avidity, selected clones were reformatted as bivalent diabodies and monoclonal antibodies (mAb). The highest affinity mAb completely neutralized live SARS-CoV-2 virus in cell culture for four days at a concentration of 6.7 nM, suggesting potential therapeutic and/or prophylactic use. Furthermore, scFvs were identified that greatly increased the interaction of the viral S1 trimer with the ACE2 receptor, with potential implications for vaccine development. Copy rights belong to original authors. Visit the link for more info