The merozoite surface protein 1 (MSP1) has emerged as a leading malaria vaccine candidate at the erythrocytic stage. Recombinant bacillus Calmette-Guérin (rBCG), which expressed a COOH-terminal 15-kD fragment of MSP1 of Plasmodium yoelii (MSP1-15) as a fusion protein with a secretory protein of Mycobacterium kansasii, was constructed. Immunization of mice with this rBCG induced a higher degree ...

Two strains of transgenic mice have been generated that secrete into their milk a malaria vaccine candidate, the 42-kDa C-terminal portion of Plasmodium falciparum merozoite surface protein 1 (MSP1(42)). One strain secretes an MSP1(42) with an amino acid sequence homologous to that of the FVO parasite line, the other an MSP1(42) where two putative N-linked glycosylation sites in the FVO sequenc...

Antibodies against the 19 kDa C-terminal fragment of merozoite surface protein 1 (MSP1(19)) are a major component of the invasion-inhibitory response in individuals immune to malaria. We report here the acquisition of MSP1(19)-specific invasion-inhibitory antibodies in a group of transmigrants who experienced their sequential malaria infections during settlement in an area of Indonesia where ma...

Antigen-specific antibodies (Abs) to the 19-kDa carboxy-terminal region of Plasmodium falciparum merozoite surface protein 1 (MSP1(19)) play an important role in protective immunity to malaria. Mouse monoclonal Abs (MAbs) 12.10 and 12.8 recognizing MSP1(19) can inhibit red cell invasion by interfering with MSP1 processing on the merozoite surface. We show here that this ability is dependent on ...

One of the most promising vaccine candidates against the erythrocytic forms of malaria is the 19 kDa C-terminal region of the merozoite surface protein 1 (MSP1(19)). As part of our studies aimed at the development of a Plasmodium vivax malaria vaccine, we characterized the immunogenic properties of a new bacterial recombinant protein containing the P. vivax MSP1(19) and two helper T-cell epitop...

BACKGROUND Two current leading malaria blood-stage vaccine candidate antigens for Plasmodium falciparum, the C-terminal region of merozoite surface protein 1 (MSP1(19)) and apical membrane antigen 1 (AMA1), have been prioritized because of outstanding protective efficacies achieved in a rodent malaria Plasmodium yoelii model. However, P. falciparum vaccines based on these antigens have had disa...

The malaria parasite Plasmodium falciparum invades erythrocytes where it replicates to produce invasive merozoites, which eventually egress to repeat the cycle. Merozoite surface protein-1 (MSP1), a prime malaria vaccine candidate and one of the most abundant components of the merozoite surface, is implicated in the ligand-receptor interactions leading to invasion. MSP1 is extensively proteolyt...

Msp1 is a conserved AAA ATPase in budding yeast localized to mitochondria where it prevents accumulation of mistargeted tail-anchored (TA) proteins, including the peroxisomal TA protein Pex15. Msp1 also resides on peroxisomes but it remains unknown how native TA proteins on mitochondria and peroxisomes evade Msp1 surveillance. We used live-cell quantitative cell microscopy tools and drug-induci...

Naturally acquired immunity to Plasmodium falciparum malaria in malaria holoendemic areas is characterized by the gradual, age-related development of protection against high-density parasitemia and clinical malaria. Animal studies, and less commonly, observations of humans with malaria, suggest that T-cell responses are important in the development and maintenance of this immunity, which is med...

Vaccine adjuvants exert critical and unique influences on the quality of immune responses induced during active immunizations. We investigated the mechanisms of action of immunological adjuvants in terms of their requirements for cytokine-mediated pathways for adjuvanticity. Antibody responses potentiated by several adjuvants to a Plasmodium falciparum MSP1-19 (C-terminal 19-kDa processing frag...