Fig. 2.
N6 antigen binding assessment. A ELISA demonstrating specific binding of anti-HIV antibody to its cognate antigen—gp140. Purified pN6 antibody (triangle), commercially-sourced human IgG1 kappa (square) and VRC01 (circle) were incubated on an ELISA plate coated with gp140. VRC01 (circle) was previously purified from tobacco plants in-house. Bound antibodies were detected using HRP-conjugated goat anti-human IgG Fc domain antibody. Human IgG kappa (square) was included as a negative control at 100 ng/ml only. Representative of 3 biological replicates. ELISAs were performed with 2 technical replicates. Data shown are mean ± S.D. B Surface plasmon resonance measuring binding kinetics of pN6 antibody compared to mN6. Protein A was immobilised onto a CM5 chip and N6 antibody was captured to 5000 RU. C Calculated association constant (ka), dissociation constant (kd) and affinity (KD) from surface plasmon resonance were estimated using the Langmuir model of binding (1:1), with BIAcore™ Evaluation software. Both versions of N6 bind to gp140 with an equivalent affinity