Receptor mediated endocytosis of the malarial parasite by erythrocytes.

Malarial merozoites appear to interact with the major surface sialoglycoproteins, glycophorin A and glycophorin B, during entry into the human erythrocyte. Intact merozoites bind 125I-glycophorin demonstrating directly that the parasites have glycophorin binding sites. A glycophorin containing fraction crosslinked to acrylamide beads provided a probe to identify merozoite molecules with an affinity for the erythrocyte surface. A fraction of merozoites, labeled with 3H-proline, and containing the membrane proteins and a fraction containing soluble proteins released by the merozoite were added to the glycophorin beads. Two proteins, M.W. of 155,000 and 130,000, specifically bound to glycophorin. These proteins may represent the merozoite recognition site for the erythrocyte.