HUMORAL IMMUNE-RESPONSES IN GAMBIANS TO PFS16, AN IMMUNODOMINANT, PLASMODIUM-FALCIPARUM INTEGRAL MEMBRANE-PROTEIN

Naturally acquired humoral immune responses to Pfs16, an integral memb rane protein expressed in Plasmodium falciparum gametocytes and sporoz oites, were investigated in The Gambia. A high prevalence of antibodie s to this molecule was detected by peptide ELISA. Ninety-three per cen t of the people taking part in a survey at the end of the rainy season (November) had serum antibodies to one or more synthetic peptides spa nning the sequence, 88% reacted with one particular peptide sequence ( IMLIILSGIVGFRVK) whereas only one out of ten non-Gambians (taking anti -malarial prophylaxis with no history of infection) reacted with the p eptide. Epitope mapping with mouse MoAbs has shown that this peptide i s located on a part of the molecule differing from immunodominant regi ons of the molecule identified in a previous study in Papua New Guinea .