Malaria parasites release vesicle subpopulations with signatures of different destinations.
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ABSTRACT:
SUBMITTER: Abou Karam P
PROVIDER: S-EPMC9253735 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Abstract Malaria is the most serious mosquito-borne parasitic disease, caused mainly by the intracellular parasite Plasmodium falciparum. This parasite invades human red blood cells and releases extracellular vesicles (EVs) to alter its host responses. It becomes clear that EVs are generally composed of sub-populations. Seeking to identify the various EV subpopulations we subjected malaria-derived EVs to size-separation analysis, using Asymmetric Flow Field-Flow Fractionation. Multi-technique analysis revealed surprising characteristics: two distinct EV subpopulations differing in size and protein content were identified. The small EVs were enriched in complement-system proteins and the large EVs with proteasome subunits. We then measured the membrane fusion abilities of each subpopulation with three types of host cellular membranes: plasma, late and early endosome. Remarkably, small EVs fused to early-endosome liposomes at significantly greater levels than large EVs. Combined atomic force microscope with machine-learning methods further emphasize the difference in biophysical properties between the two subpopulations. These results shed light on the sophisticated mechanism by which malaria parasites utilize EV subpopulations as a communication tool to target different cellular destinations or host systems.
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