Plasmodium falciparum erythrocyte membrane protein 1 functions as a ligand for P-selectin

The malarial protein Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) is a parasite protein that is exported to the surface of the infected erythrocyte, where it is inserted into the red cell cytoskeleton in the second half of the parasite life cycle. The surface expression of PfEMP1 coincides with the occurrence of the adhesion of infected erythrocytes to vascular endothelium. This protein has been shown to interact with CD36, intercellular adhesion molecule-1 (ICAM-1) and chondroitin sulfate A (CSA). In this study, it is demonstrated by affinity purification and western blot analysis that PfEMP1 also functions as a cell surface ligand for P-selectin, an adhesion molecule that has been shown to mediate the rolling of infected erythrocytes under physiologic flow conditions, leading to a significant increase in adhesion to CD36 on activated platelets and microvascular endothelium.