ANTIBODY-RESPONSES TO RHOPTRY-ASSOCIATED PROTEIN-1 (RAP-1) OF PLASMODIUM-FALCIPARUM PARASITES IN HUMANS FROM AREAS OF DIFFERENT MALARIA ENDEMICITY

Plasma IgM and IgG antibody reactivities against the recombinant Plasm odium falciparum protein, Rhoptry, Associated Protein-1 (rRAP-1) were measured by ELISA in individuals from Sudan, Indonesia, Kenya and The Gambia living in areas of different malaria endemicity. IgG and IgM re activities to rRAP-1 increased with malaria endemicity. IgG reactiviti es were associated with spleen rates in Indonesia with high malaria en demicity while IgM reactivities were associated with spleen rates in K enya with low malaria endemicity. Ige and IgM reactivities to rRAP-1 i ncreased during acute episodes of P. falciparum malaria in Sudanese ad ults and IgG reactivities remained high one month after treatment in a ll adults tested Antibody reactivities to rRAP-1 in Gambian children i n the dry season were higher in children with parasitaemia than in chi ldren without detectable parasitaemia. Antibody reactivities were not associated with protection against clinical episodes in the following rainy season brit higher antibody reactivities were detectable at the end of the rainy season. There was no difference in antibody reactivit y to rRAP-1 between Gambian children with mild or severe malaria.