Figure 2.

Stability and antigenicity of GPΔmucin are not perturbed when displayed on protein nanoparticles. (A) Stability of GP-GCN4, GP-Fer, and GP-E2p were assessed using differential scanning fluorimetry using a melting gradient from 20°C to 90°C at a rate of 1°C per minute. Melting temperatures were obtained from the Prometheus software using the fit of the first derivative of the 350/330 nm fluorescence ratio as a function of temperature. (B) 2D class averages from cryo-EM analysis of GP-Fer and GP-E2p. (C) Binding of mAbs to GP-GCN4, GP-Fer, and GP-E2p was assessed using purified mAbs immobilized on anti-human Fc biosensor tips. mAbs were dipped into antigen (100 nM, subunit concentration) and association was monitored for 3 min. Binding experiments were performed in experimental duplicate and k_on values were calculated by fitting curves with an association/dissociation kinetic equation in GraphPad Prism. Binding curves from one representative replicate are shown with curve fits plotted as hashed black lines. Average k_on values for each binding reaction with standard deviation are shown in table.