Fig. 3. SARS-CoV-2 S2 domain antibodies cross-react with hCoV.
Plasma from SARS-CoV-2 seropositive children (n = 21) was assessed for binding to the spike protein of the 4 hCoVs or the spike or nucleocapsid regions of SARS-CoV-2. Plasma was either applied neat (control) or after preabsorption with either recombinant spike S1 domain (spike 1 block) or spike S2 domain (spike 2 block). S1 preabsorption markedly reduced binding to SARS-CoV-2 spike with no effect on hCoV, while S2 preabsorption reduced binding to OC43 and HKU-1. One-way repeated measures ANOVA with Holm–Sidak’s multiple comparison test or Friedman test with Dunn’s multiple comparisons test were used as appropriate.