Beyond lysozyme : antimicrobial peptides against malaria

Antimicrobial peptides (AMPs) are short amino acidic sequences with less than 100 residues. They are the components of the innate immune system not only in humans but also in plants, insects, and primitive multicellular organisms. Their role is to counteract the microorganisms, which could be potentially pathogenic for the host. AMPs active against viruses, bacteria, fungi, and parasites have been described. Among the antiparasitic AMPs reported so far, some peptides affect Plasmodium development in different phases of the biological cycle, from asexual blood stages to sexual stages in the mosquito, where AMPs can block ookinetes viability or oocyst formation. AMPs with antimalarial activity derive from different organisms, especially insects, as well as amphibians. In malaria research, AMPs have been mainly proposed for the engineering of mosquitoes or parasites to reduce or interrupt the malaria parasite transmission. In this chapter, the different classes of antimalarial AMPs (defensins, cecropins, dermaseptins) or single peptides (scorpine, melittin, gambicin) are described.