Human antibodies to the 19kDa C-terminal fragment of Plasmodium falciparum merozoite surface protein 1 inhibit parasite growth in vitro.
The 19kDa, C-terminal fragment of the major surface protein of Plasmodium falciparum (PfMSP1(19)) is a candidate for inclusion in a subunit malaria vaccine. In this study, we show that PfMSP1(19)-specific antibodies, affinity purified from malaria-immune human serum, can: (i) compete with invasion-inhibitory monoclonal antibodies for binding to PfMSP1(19) and (ii) mediate inhibition of parasite growth in vitro, in the absence of complement and mononuclear cells, at physiological antibody concentrations (100 micrograms/ml). Parasites expressing either the Kl or 3D7 allele of PfMSP1(19) were equally susceptible to inhibition of merozoite invasion, indicating that the target epitopes of inhibitory antibodies are conserved or cross-reactive. These studies suggest that vaccines designed to induce antibodies to PfMSP1(19) may protect against the high levels of malaria parasitaemia which are associated with clinical disease.
Egan
A F
AF
Institute of Cell, Animal and Population Biology, University of Edinburgh, Scotland, UK.
Burghaus
P
P
Druilhe
P
P
Holder
A A
AA
Riley
E M
EM
D000328:Adult; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000913:Antibodies, Protozoan / Q000276:immunology* / Q000302:isolation & purification; D002846:Chromatography, Affinity; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D016778:Malaria, Falciparum / Q000276:immunology*; D020066:Merozoite Surface Protein 1 / Q000276:immunology*; D010963:Plasmodium falciparum / Q000254:growth & development / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000913:Antibodies, Protozoan; D020066:Merozoite Surface Protein 1