Oral Presentation Lorne Infection and Immunity 2014

Plasmodium nesting: remaking the erythrocyte from the inside out (#14)

Alan Cowman 1
  1. Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia

In humans the most severe form of malaria is caused by Plasmodium falciparum and at least a third of the world's population is at risk of infection, with over three hundred million people developing clinical disease each year and over 700,000 deaths. P. falciparum invades human erythrocytes using several specific and high affinity ligand-receptor interactions that define invasion pathways. Once inside the erythrocyte the parasite initiates a remarkable process of remodelling that converts a specialized terminally differentiated host cell into one in which the parasite can harvest the essential nutrients for growth as well as provide a protected niche allowing escape from host responses. To establish infection in the host, malaria parasites export hundreds of remodelling and virulence proteins into the erythrocyte. These proteins must traverse a series of membranes including the parasite, parasitophorous vacuole and erythrocyte membrane. This includes P. falciparum erythrocyte membrane protein 1 (PfEMP1), which is a major virulence determinant. This large protein is displayed on the surface of the infected erythrocyte and responsible for cytoadherence and it plays an important role in malaria pathogenesis. Although numerous studies have focused on the transport of this molecule many aspects about its pathway to the surface of the host cell are still elusive. We have identified previously unknown roles for proteins in remodelling of the P. falciparum-infected erythrocyte and provide a basis for understanding the function of exported parasite molecules in host-parasite interactions.