Fig. 2. Structure and conservation of the NPNA₂ epitope.

a Surface model of a single Fab from 337-rsCSP structure, showing only the core epitope NPNA₂ in gold. The heavy chain is colored dark gray, and light chain is in light gray. b Superposition of a single Fab and NPNA₂ from each of the seven cryo-EM structures. Same coloring as in a. c Zoomed-in view of the paratope of 337, highlighting two hydrophobic pockets, Site 1 and Site 2. d CH–π interactions of CDRH2 and CDRL3 residues with Pro in the NPNA repeat. e, f Full epitope structure of 334 and 356, showing N and C-terminal extensions beyond NPNA₂, which are labeled as residues 1–8. g, h Buried surface area (BSA) contributions by each residue within the full epitope of 334 (g) and 356 (h). See also Fig. S2. Source data are provided as a Source Data file.