Miniaturized assay to evaluate Plasmodium cynomolgi and P. knowlesi as models for prioritizing P. vivax vaccine targets.

Abstract

Plasmodium vivax vaccine discovery lags behind P. falciparum due to the absence of a reliable in vitro culture system. We developed a miniature 384-well assay for the evolutionarily related parasite species P. cynomolgi and P. knowlesi, deploying it for screening invasion inhibition efficacy of antibodies elicited against 8 P. vivax proteins. All 8 antibodies showed consistent inhibition across both P. knowlesi and P. cynomolgi species, correlating with inhibition in ex vivo P. vivax isolates. The use of simian malaria parasites and this assay represents a robust, high-throughput method for prioritizing P. vivax blood stage vaccine candidates.