Activation of complement-like antiparasitic responses in Anopheles mosquitoes

During their development in mosquitoes, malaria parasites undergo massive losses that are in part due to a potent antiparasitic response mounted by the vector. The most efficient and best-characterized response relies on a complement-like system particularly effective against parasites as they cross the mosquito midgut epithelium. While our vision of the molecular and cellular events that lead to parasite elimination is still partial, our understanding of the steps triggering complement activation at the surface of invading parasites has considerably progressed, not only through the identification of novel contributing genes, but also with the recent in-depth characterization of the different mosquito blood cell types, and the ability to track them in live mosquitoes. Here, we propose a simple model based on the time of invasion to explain how parasites may escape complement-like responses during midgut infection.