PLASMODIUM-FALCIPARUM GAMETOCYTE ADHESION TO C32 CELLS VIA CD36 IS INHIBITED BY ANTIBODIES TO MODIFIED BAND-3

Plasmodium falciparum gametocyte-infected erythrocytes are characteriz ed by their ability to sequester in the microvasculature of various or gans, primarily the spleen and bone marrow, This phenomenon is thought to play a critical role in the development and survival of the sexual stages. Little is known, however, about ligands on the gametocyte-inf ected erythrocyte, Infection of erythrocytes with mature asexual stage s of P. falciparum (trophozoites and schizonts) has been shown to indu ce modification of the erythrocyte anion transporter, band 3, and this has been linked to the acquisition of an adherent phenotype. Here, we demonstrate for the first time that immature gametocyte-infected eryt hrocytes also express modified band 3, In vitro binding assays demonst rate that gametocyte-infected erythrocytes of the 3D7 strain utilize t his surface receptor for adhesion to C32 amelanotic melanoma cells via the host cell receptor CD36 (platelet glycoprotein IIIb). Adhesion of gametocyte-infected erythrocytes to CD36-transfected CHO cells is als o dependent on modified band 3. However, modified band 3 does not medi ate adhesion of gametocyte-infected erythrocytes to intercellular adhe sion molecule 1, a second host receptor for gametocytes expressed on C 32 cells.