Researchers at the Johns Hopkins Malaria Research Institute identified a sugar in mosquitoes that allows the malaria-causing parasite, Plasmodium falciparum, to attach itself to the mosquito’s gut.
Invasion of the midgut cell layer is an essential stage in the parasite’s lifecycle and in the transmission of malaria from mosquitoes to humans. By reducing the level of the sugar, chondroitin sulfate, in the mosquito, the researchers prevented 95% of the parasites from attaching to the gut, thus blocking its development.
To determine whether the parasite utilizes chondroitin glycosaminoglycans to invade the mosquito midgut cells, the researchers used RNAi to inhibit production of a mosquito enzyme that is needed to produce chondroitin sulfate. With the sugar removed, parasite adhesion and midgut invasion were substantially decreased.
The study is published in the online early edition of Proceedings of the National Academy of Sciences.