ANOPHELES-STEPHENSI SALIVARY-GLANDS BEAR RECEPTORS FOR REGION-I OF THE CIRCUMSPOROZOITE PROTEIN OF PLASMODIUM-FALCIPARUM

In the mosquito, Plasmodium sporozoites rupture from oocysts found on the midgut wall, circulate in the hemolymph and invade salivary glands where they wait to be injected into a vertebrate host during a bloodm eal. The mechanisms by which sporozoites specifically attach to and in vade salivary glands are not known but evidence suggests that it is a receptor-mediated process. Here we show that the major surface protein of sporozoites, the circumsporozoite protein (CS), binds preferential ly to salivary glands when compared to other organs exposed to the cir culating hemolymph. In addition, we show that a peptide encompassing r egion I, a highly conserved sequence found in all rodent and primate P lasmodium CS proteins, inhibits binding of CS to mosquito salivary gla nds. (C) 1997 Elsevier Science B.V.