Functional and immunological mapping of domains of the reticulocyte binding protein, Plasmodium vivax PvRBP2a.
Tay MZ., Tang W., Lee W-C., Ong ASM., Novera W., Malleret B., Carissimo G., Chacko A-M., El-Sahili A., Lescar J., Fan Y., McGready RM., Chu CS., Chan JKY., Ng LFP., Russell B., Nosten F., Rénia L.
We previously described a novel Plasmodium vivax invasion mechanism into human reticulocytes via the PvRBP2a-CD98 receptor-ligand pair. We assessed the PvRBP2a epitopes involved in CD98 binding and recognised by antibodies from infected patients using linear epitope mapping. We identified two epitope clusters mediating PvRBP2a-CD98 interaction. One cluster named cluster B (PvRBP2a431-448, TAALKEKGKLLANLYNKL) was the target of antibody responses in P. vivax-infected humans. Peptides from each cluster were able to prevent live parasite invasion of human reticulocytes. These results provide new insights for development of a malaria blood stage vaccine against P. vivax.