PLASMODIUM-FALCIPARUM - PFALHESIN AND CD36 FORM AN ADHESIN RECEPTOR PAIR THAT IS RESPONSIBLE FOR THE PH-DEPENDENT PORTION OF CYTOADHERENCE/SEQUESTRATION/

The cytoadherent behavior of two Plasmodium falciparum (human malaria) cell lines, FCR-3 and IT04 (a cell line with elevated ICAM-1 adherenc e), was studied using CHO cells transfected with CD36 or ICAM-1 recept ors as target cells. ICAM-1-mediated adherence was found to be relativ ely pH insensitive, whereas CD36-mediated adherence was pH sensitive a nd inhibited by monoclonal antibodies and peptides based on a region f ound in human band 3 protein and named pfalhesin. Immobilized pfalhesi n was used as an affinity matrix to purify CD36 from extracts of C32 a melanotic melanoma cells, which have ICAM-1 as well as CD36 receptors, and bind both parasite cell lines. We conclude that pfalhesin and CD3 6-constitute an adhesin/receptor pair. (C) 1994 Academic Press, Inc.