Fig. 5. Isolation and characterization of epitope scaffold reactive antibodies from subjects with pre-existing SARS-CoV-2 immunity.
a Sera binding profile of subjects from which B cells were isolated. Binding was measured to the synthetic peptide epitope, the epitope scaffold used as the sorting probe, and the corresponding parent scaffold (PS) that lacks the epitope and was employed for negative selection. b Representative FACS plots of memory B cells labeled with epitope scaffold probes. Cells from Subject 26 were labeled with S2hlx-Ex19 conjugated to VB15 (x-axis) and AF647 (y-axis). A third bait comprising S2hlx-Ex19 PShlx conjugated to BV421 was used to exclude scaffold-specific memory B cells. c Binding of the isolated antibodies to diverse CoV spikes. d Neutralization of diverse pseudoviruses by isolated stem helix antibodies. CoV-1 = SARS-CoV-1. All other pseudoviruses are the indicated variant of SARS-CoV-2. e Binding of isolated antibodies to cells infected with two different SARS-CoV-2 VOCs (D614G, top; BA.1, bottom). Antibodies in red have been previously described, those depicted in green were isolated here, while those in blue represent controls; DH1047 targets the RBD domain; DH1058 targets the spike815–823 peptide domain; anti-HIV antibody VRC01 was included as a negative control. f NK cell degranulation ability of mAbs from (e). Source data are provided as a Source Data file.