Characterization of a Plasmodium falciparum PHISTc protein, PF3D7_0801000, in blood- stage malaria parasites. (February 2021)

• Record Type: Journal Article
• Authors: Nagaoka, Hikaru; Kanoi, Bernard N.; Morita, Masayuki; Nakata, Takahiro; Palacpac, Nirianne M.Q.; Egwang, Thomas G.; Horii, Toshihiro; Tsuboi, Takafumi; Takashima, Eizo
• Is Part Of: Parasitology international. Volume 80(2021)
• Publication Date: 2021-02
• Subjects: Malaria -- Plasmodium falciparum -- PHISTc -- PF3D7_0801000 -- Blood-stage vaccine; PHIST Plasmodium (also "Poly-") Helical Interspersed Sub-Telomeric -- GIA growth inhibition assay -- WGCFS wheat germ cell-free system; Parasitology -- Periodicals; Parasites -- Periodicals; Parasitic Diseases -- Periodicals; Parasitology -- Periodicals; Parasitologie -- Périodiques; 571.99905
• DOI: 10.1016/j.parint.2020.102240
• Languages: English
• ISSNs: 1383-5769

Abstract

Abstract: During intraerythrocytic development Plasmodium falciparum deploys numerous proteins to support erythrocyte invasion, intracellular growth and development, as well as host immune evasion. Since these proteins are key for parasite intraerythrocytic survival and propagation, they represent attractive targets for antimalarial vaccines. In this study we sought to characterize a member of the PHISTc family of proteins, PF3D7_0801000, as a potential vaccine target. Using the wheat germ cell-free system we expressed the N-terminal region of PF3D7_0801000 (G93 -L494, PF3D7_0801000N) and generated specific immune sera. We observed that PF3D7_0801000 localizes in merozoites, and antibodies against PF3D7_0801000N modestly inhibit P. falciparum parasite growth in in vitro culture. Sliding window analysis of the coding sequence revealed that pf3d7_0801000n is relatively conserved among African parasite isolates. Antibody profiles in a malaria-exposed Ugandan population revealed that PF3D7_0801000N is strongly immunoreactive with antibody acquisition increasing with age. Taken together, these findings suggest the need for further evaluation of PF3D7_0801000 for its role in merozoite invasion and utility as an asexual blood-stage vaccine candidate antigen. Highlights: Anti-PF3D7_0801000 antibodies inhibit P. falciparum parasite growth in vitro . The N-terminal region of PF3D7_0801000 is relatively conserved among African parasite isolates. PF3D7_0801000 is immunogenic in a malaria-exposed Ugandan population.