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Nutritional Conditions Modulate C. neoformans Extracellular Vesicles' Capacity to Elicit Host Immune Response.

ABSTRACT: Cryptococcus neoformans is a human pathogenic fungus that mainly afflicts immunocompromised patients. One of its virulence strategies is the production of extracellular vesicles (EVs), containing cargo with immunomodulatory properties. We evaluated EV's characteristics produced by capsular and acapsular strains of C. neoformans (B3501 and ?Cap67, respectively) growing in nutritionally poor or rich media and co-cultures with bone marrow-derived macrophages or dendritic cells from C57BL/6 mice. EVs produced under a poor nutritional condition displayed a larger hydrodynamic size, contained more virulence compounds, and induced a more robust inflammatory pattern than those produced in a rich nutritional medium, independently of strain. We treated infected mice with EVs produced in the rich medium, and the EVs inhibited more genes related to the inflammasome than untreated infected mice. These findings suggest that the EVs participate in the pathogenic processes that result in the dissemination of C. neoformans. Thus, these results highlight the versatility of EVs' properties during infection by C. neoformans in different tissues and support ongoing efforts to harness EVs to prevent and treat cryptococcosis.

SUBMITTER: Marina CL

PROVIDER: S-EPMC7698703 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

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Nutritional Conditions Modulate C. neoformans Extracellular Vesicles' Capacity to Elicit Host Immune Response.

Marina Clara Luna CL Bürgel Pedro Henrique PH Agostinho Daniel Paiva DP Zamith-Miranda Daniel D Las-Casas Lucas de Oliveira LO Tavares Aldo Henrique AH Nosanchuk Joshua Daniel JD Bocca Anamelia Lorenzetti AL

Microorganisms 20201118 11

Cryptococcus neoformans is a human pathogenic fungus that mainly afflicts immunocompromised patients. One of its virulence strategies is the production of extracellular vesicles (EVs), containing cargo with immunomodulatory properties. We evaluated EV's characteristics produced by capsular and acapsular strains of C. neoformans (B3501 and ΔCap67, respectively) growing in nutritionally poor or rich media and co-cultures with bone marrow-derived macrophages or dendritic cells from C5 ...[more]

PMID: 33217920

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Dataset Information

Nutritional Conditions Modulate C. neoformans Extracellular Vesicles' Capacity to Elicit Host Immune Response.

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Nutritional Conditions Modulate <i>C. neoformans</i> Extracellular Vesicles' Capacity to Elicit Host Immune Response.

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