Properties of epitopes of Pfs 48/45, a target of transmission blocking monoclonal antibodies, on gametes of different isolates of Plasmodium falciparum.

摘要: We have studied the properties of epitopes on Plasmodium falciparum gamete surface protein Pfs 48/45, a target antigen malaria transmission blocking antibodies. Using two site immunoradiometric assay we defined three spacially separate, non-repeated, epitope regions peptides representing this antigen. Epitope region I is monoclonal antibodies (MoAbs) which strongly suppress infectivity gametocytes P. to mosquitoes; effect complement independent and mediated as effectively by monovalent Fab fragments intact MoAb. II consists close subregions, IIa IIb; variant forms IIb occurred in different isolates falciparum. III also showed slight structural modification between isolates. MoAbs against or were relatively ineffective suppressing gametocyte compared I. However, certain combinations together acted synergistically mosquitoes. All these failed react with MoAb when was presented reduced form. A fourth epitope, however, identified reacted The had no