Circumsporozoite protein gene of Plasmodium simium, a Plasmodium vivax-like monkey malaria parasite.

Abstract

The circumsporozoite (CS) protein, a species-specific sporozoite surface protein and a vaccine candidate antigen, has been characterized from malaria parasites that naturally cause infections in humans, monkeys and chimpanzees [1-7]. Because of the related structural features of repetitive and nonrepetitive sequences the CS protein genes have also been used as markers for studies of evolutionary relatedness of malaria parasites [8]. The CS protein genes of the nonhuman primate malaria parasites Plasmodium brazilianurn and Plasmodium reichenowi, which are considered to be evolutionarily related to the human malaria parasites Plasrnodium malariae and Plasmodium falciparum, respectively, have been characterized and shown to bear structural and antigenic similarity [4,7]. Plasmodium simium is a nonhuman malaria parasite both morphologically and biologically similar to the human malaria parasite Plasmo-