Assessing the functional impact of PfRh5 genetic diversity on ex vivo erythrocyte invasion inhibition.

The PfRh5-Basigin ligand-receptor interaction is an essential step in the merozoite invasion process and represents an attractive vaccine target. To reveal genotype-phenotype associations between naturally occurring allelic variants of PfRh5 and invasion inhibition, we performed ex vivo invasion inhibition assays with monoclonal antibodies targeting basigin coupled with PfRh5 next-generation amplicon sequencing. We found dose-dependent inhibition of invasion across all isolates tested, and no statistically significant difference in invasion inhibition for any single nucleotide polymorphisms. This study demonstrates that PfRh5 remains highly conserved and functionally essential, even in a highly endemic setting, supporting continued development as a strain-transcendent malaria vaccine target.