Enzyme-linked immunosorbent assay (ELISA)
AVGIGA
Anti-fusion peptide ELISA was performed by coating 96-well plates (Costar High Binding Half-Area; Corning, Kennebunk, ME) overnight at 4°C with 50 μL/well of 2 μg/mL FP8v1-rTTHC (AVGIGAVF), FP7v1-rTTHC (AVGIGAV), or FP6v1-rTTHC (AVGIGA) in PBS. Between each subsequent step, plates were washed five times with PBS-T (PBS plus 0.05% Tween) unless otherwise stated. Plates were blocked with 100 μL/well of in-house B3T blocking solution (30 mM NaCl, 10 mM Tris-HCl, 0.2 mM EDTA, 0.66% fetal bovine serum [FBS], 0.4% bovine albumin, 0.014% Tween 20, 0.004% thimerosal) for 1 h at 37°C. Next, 50 μL/well of serially diluted 2C06 or 2C09 antibody (7-point, 5-fold, 2 μg/mL starting concentration) were added to the plates and incubated for 1 h at 37Competition ELISA for antibody binding to BG505 DS-SOSIP was performed by coating 96-well plates (Costar High Binding Half-Area; Corning, Kennebunk, ME) overnight at 4°C with 50 μL/well of 2 μg/mL snowdrop lectin from 