# Functional and Immunologic Mapping of Domains of the Reticulocyte-Binding Protein Plasmodium vivax PvRBP2a

## TL;DR

This study identifies key regions of a protein involved in malaria parasite invasion, which could help in developing a blood-stage vaccine for Plasmodium vivax.

## Contribution

The paper identifies two epitope clusters in PvRBP2a critical for CD98 binding and vaccine development.

## Key findings

- Two epitope clusters in PvRBP2a mediate interaction with CD98.
- Antibodies from infected patients target cluster B (PvRBP2a431-448).
- Peptides from these clusters can block parasite invasion of reticulocytes.

## Abstract

We previously described a novel Plasmodium vivax invasion mechanism into human reticulocytes via the PvRBP2a-CD98 receptor-ligand pair. Using linear epitope mapping, we assessed the PvRBP2a epitopes involved in CD98 binding and recognized by antibodies from patients who were infected. We identified 2 epitope clusters mediating PvRBP2a-CD98 interaction. Cluster B (PvRBP2a431-448, TAALKEKGKLLANLYNKL) was the target of antibody responses in humans infected by P vivax. 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.

Here, we identify 2 clusters of epitopes mediating the functional interaction between the Plasmodium vivax invasion ligand PvRBP2a and its host receptor CD98. Our data reveal important epitopes for development of a P vivax blood-stage vaccine.