The journey of the malaria sporozoite through its hosts: two parasite proteins lead the way

Malaria is transmitted to a mammalian host when the sporozoite stage of the Plasmodium parasite is injected by a mosquito vector. Sporozoites are uniq ue in being able to interact with both hosts. Formed and released in the mo squito midgut, sporozoites bind to the salivary glands and invade their sec retory cells. Once injected into the mammalian host, they home to the liver and invade hepatocytes. Recent work has shown that two sporozoite surface proteins, CS and TRAP, act in both hosts,perform multiple functions, and ar e each essential for the parasite at more than one step of its life cycle. (C) 2000 Editions scientifiques et medicales Elsevier SAS.