Uncovering the Role of Erythrocyte-Derived Extracellular Vesicles in Malaria: From Immune Regulation to Cell Communication

Abstract

Investigation of the involvement of extracellular vesicles (EVs) in parasite biology has burgeoned in recent years. Human infecting protozoan parasites, such as Trypanosoma cruzi, Lesihmania sp. and Trichomonas vaginalis, have all demonstrated the utilization of EVs as virulence factors in order to activate or hamper host immunity. Novel findings have provided evidence that the deployment of EVs by Plasmodium sp. has a major impact in disease outcomes and serves as an integral part in controlling stage switching in its life cycle. Clinical studies have highlighted elevated levels of EVs in patients with severe malaria disease and EVs have been linked to increased sequestration of infected red blood cells to the endothelium, causing obstruction of blood flow. It has also been found that EVs produced during malaria disease activate innate immunity. Intriguingly, recent discoveries indicate that Plasmodium sp. “highjack” the erythrocyte microvesiculation system in order to cross-communicate. Both the transfer of DNA and parasite density regulation has been suggested as key mechanisms of EVs in malaria biology.