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Malaria parasites release vesicle subpopulations with signatures of different destinations.

ABSTRACT: Malaria is the most serious mosquito-borne parasitic disease, caused mainly by the intracellular parasite Plasmodium falciparum. The 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 EV subpopulations, we subject malaria-derived EVs to size-separation analysis, using asymmetric flow field-flow fractionation. Multi-technique analysis reveals surprising characteristics: we identify two distinct EV subpopulations differing in size and protein content. Small EVs are enriched in complement-system proteins and large EVs in proteasome subunits. We then measure the membrane fusion abilities of each subpopulation with three types of host cellular membranes: plasma, late and early endosome. Remarkably, small EVs fuse to early endosome liposomes at significantly greater levels than large EVs. Atomic force microscope imaging combined with machine-learning methods further emphasizes 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.

SUBMITTER: Abou Karam P

PROVIDER: S-EPMC9253735 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature

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Malaria parasites release vesicle subpopulations with signatures of different destinations.

Abou Karam Paula P Rosenhek-Goldian Irit I Ziv Tamar T Ben Ami Pilo Hila H Azuri Ido I Rivkin Anna A Kiper Edo E Rotkopf Ron R Cohen Sidney R SR Torrecilhas Ana Claudia AC Avinoam Ori O Rojas Alicia A Morandi Mattia I MI Regev-Rudzki Neta N

EMBO reports 20220601 7

Malaria is the most serious mosquito-borne parasitic disease, caused mainly by the intracellular parasite Plasmodium falciparum. The 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 EV subpopulations, we subject malaria-derived EVs to size-separation analysis, using asymmetric flow field-flow fractionation. Multi-technique analysis reveals surprisi ...[more]

PMID: 35642585

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Malaria parasites release vesicle subpopulations with signatures of different destinations.

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Malaria parasites release vesicle subpopulations with signatures of different destinations.

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