Disclaimer: This is a summary of an article that is in preprint and has not been peer reviewed.
A recent pre-peer reviewed article in medRxiv reports on the dynamics of neutralizing antibody responses to the receptor-binding domain (RBD) of the spike protein. The investigators examined 44 COVID-19 patients and found that class-switching occurred early during infection and was dominated by RBD-specific IgG1 and IgG3 responses. They also detected both RBD-specific IgM and IgA responses at relatively lower levels as compared to IgG. The RBD-specific IgG responses were detected as early as 6 days after PCR confirmation which correlated with the presence of neutralizing antibodies against a clinical isolate of SARS-CoV-2. These findings show that a robust humoral immune response occurs during the acute stage of COVID-19 infection. The authors conclude: “The appearance of high titer neutralizing antibody responses early after the infection is promising and may offer some degree of protection from re-infection”.
Journal Article: Suthar et al., (Pre-Print). Rapid generation of neutralizing antibody responses in COVID-19 patients. medRxiv
Summary by Clive Gray