Rapid generation of neutralizing antibody responses in COVID-19 patients

Suthar, Mehul S; Zimmerman, Matthew; Kauffman, Robert; Mantus, Grace; Linderman, Susanne; Vanderheiden, Abigail; Nyhoff, Lindsay; Davis, Carl; Adekunle, Seyi; Affer, Maurizio; Sherman, Melanie; Reynolds, Stacian; Verkerke, Hans; Alter, David N; Guarner, Jeannette; Bryksin, Janetta; Horwath, Michael; Arthur, Connie; Saakadze, Natia; Smith, Geoffrey Hughes; Edupuganti, Srilatha; Scherer, Erin M; Hellmeister, Kieffer; Cheng, Andrew; Morales, Juliet A; Neish, Andrew S; Stowell, Sean R; Frank, Filipp; Ortlund, Eric; Anderson, Evan; Menachery, Vineet; Rouphael, Nadine; Metha, Aneesh; Stephens, David S; Ahmed, Rafi; Roback, John; Wrammert, Jens

SARS-CoV-2 is currently causing a devastating pandemic and there is a pressing need to understand the dynamics, specificity, and neutralizing potency of the humoral immune response during acute infection. Herein, we report the dynamics of antibody responses to the receptor-binding domain (RBD) of the spike protein and virus neutralization activity in 44 COVID-19 patients. RBD-specific IgG responses were detectable in all patients 6 days after PCR confirmation. Using a clinical isolate of SARS-CoV-2, neutralizing antibody titers were also detectable in all patients 6 days after PCR confirmation. The magnitude of RBD-specific IgG binding titers correlated strongly with viral neutralization. In a clinical setting, the initial analysis of the dynamics of RBD-specific IgG titers was corroborated in a larger cohort of PCR-confirmed patients (n=231). These findings have important implications for our understanding of protective immunity against SARS-CoV-2, the use of immune plasma as a therapy, and the development of much-needed vaccines.