Sending a message: extracellular vesicles of pathogenic protozoan parasites

Protozoan parasites produce extracellular vesicles to communicate with the host and within the parasite population. In this Progress article, Hajduk and colleagues review the production and effects of extracellular vesicles from parasites, including Plasmodium spp., Trichomonas vaginalis and kinetoplastids. Parasitic unicellular eukaryotes use extracellular vesicles (EVs) as vehicles for intercellular communication and host manipulation. By using various mechanisms to generate EVs and by transferring a wide range of molecules through EVs, pathogenic protozoans are able to establish infective niches, modulate the immune system of the host and cause disease. In addition to effects on the host, EVs are able to transfer virulence factors, drug-resistance genes and differentiation factors between parasites. In this Progress article, we explore recent insights into the biology of EVs from human infectious protozoan parasites, including Trichomonas vaginalis , Plasmodium spp. and kinetoplastids, such as Trypanosoma spp. and Leishmania spp.