Antibody responses to a novel Plasmodium falciparum merozoite surface protein vaccine correlate with protection against experimental malaria infection in Aotus monkeys.

The Block 2 region of the merozoite surface protein-1 (MSP-1) of Plasmodium falciparum has been identified as a target of protective immunity by a combination of seroepidemiology and parasite population genetics. Immunogenicity studies in small animals and Aotus monkeys were used to determine the efficacy of recombinant antigens derived from this region of MSP-1 as a potential vaccine antigen. Aotus lemurinus griseimembra monkeys were immunized three times with a recombinant antigen derived from the Block 2 region of MSP-1 of the monkey-adapted challenge strain, FVO of Plasmodium falciparum, using an adjuvant suitable for use in humans.

Statistical model to evaluate in vivo activities of antimalarial drugs in a Plasmodium cynomolgi-macaque model for Plasmodium vivax malaria.

Preclinical animal models informing antimalarial drug development are scarce. We have used asexual erythrocytic Plasmodium cynomolgi infections of rhesus macaques to model Plasmodium vivax during preclinical development of compounds targeting parasite phospholipid synthesis. Using this malaria model, we accumulated data confirming highly reproducible infection patterns, with self-curing parasite peaks reproducibly preceding recrudescence peaks.

High-level expression of the malaria blood-stage vaccine candidate Plasmodium falciparum apical membrane antigen 1 and induction of antibodies that inhibit erythrocyte invasion.

Apical membrane antigen 1 (AMA-1) is a highly promising malaria blood-stage vaccine candidate that has induced protection in rodent and nonhuman primate models of malaria. Authentic conformation of the protein appears to be essential for the induction of parasite-inhibitory antibody responses. Here we have developed a synthetic gene with adapted codon usage to allow expression of Plasmodium falciparum FVO strain AMA-1 (PfAMA-1) in Pichia pastoris.

Molecular characterisation of Plasmodium reichenowi apical membrane antigen-1 (AMA-1), comparison with P. falciparum AMA-1, and antibody-mediated inhibition of red cell invasion.

Apical membrane antigen 1 is a candidate vaccine component for malaria. It is encoded by a single copy gene and has been characterised in a number of malaria species as either an 83-kDa de novo product (Plasmodium falciparum; Pf AMA-1) or a 66-kDa product (all other species). All members of the AMA-1 family are expressed during merozoite formation in maturing schizonts and are initially routed to the rhoptries.

High-level expression of Plasmodium vivax apical membrane antigen 1 (AMA-1) in Pichia pastoris: strong immunogenicity in Macaca mulatta immunized with P. vivax AMA-1 and adjuvant SBAS2.

The apical membrane antigen 1 (AMA-1) family is a promising family of malaria blood-stage vaccine candidates that have induced protection in rodent and nonhuman primate models of malaria. Correct conformation of the protein appears to be essential for the induction of parasite-inhibitory responses, and these responses appear to be primarily antibody mediated. Here we describe for the first time high-level secreted expression (over 50 mg/liter) of the Plasmodium vivax AMA-1 (PV66/AMA-1) ectodomain by using the methylotrophic yeast Pichia pastoris.