Fig. 5.

AMA1–RON2L complex induces an increase in the proportion of antibodies targeting conserved epitopes. a 3D7 AMA1-specific antibody levels in purified IgG were measured by ELISA. Arbitrary ELISA units based on standard curves were generated to compare anti-3D7 AMA1 antibody levels in purified IgG of Group 2 and Group 3 animals by Mann–Whitney test (P = 0.003). b In vitro GIA using purified IgG against the heterologous 3D7 strain. Total IgG from each animal were tested at 2.5 mg mL⁻¹ final concentration and inhibitory activity was compared between Group 2 and 3 by the Mann–Whitney test (P = 0.02). c Correlation of growth inhibitory activity of IgG from Group 3 (red squares) and Group 2 (blue circles) between homologous FVO parasites and heterologous 3D7 parasites (blue circles) (r _s = 0.89, P < 0.0001). d Structural representation of AMA1 (brown) bound to RON2L (cyan) (PDB ID: 3ZWZ).²⁰ The polymorphic residues that are conserved between FVO, 3D7 and GB4 parasites are shown in dark blue and residues that differ are shown in red. The black lines indicate the respective loops in AMA1 (Ib, Ic, Id, Ie and If) surrounding the RON2 binding site