Extracellular Vesicles Display Increased Survival but Partial Pro-Inflammatory Response by Macrophages.

Fungal extracellular vesicles (EVs) mediate intra- and interspecies communication and are critical in host-fungus interaction, modulating inflammation and immune responses. In this study, we evaluated the pro- and anti-inflammatory properties of EVs over innate leukocytes. EVs induced a partial proinflammatory response by macrophages, characterized by increased tumor necrosis factor-alpha production, and increased gene expression of induced nitric oxide synthase and adhesion molecules. EVs induce neither NETosis in human neutrophils nor cytokine secretion by peripheral mononuclear cells. However, prior inoculation of EVs in larvae resulted in increased survival after the fungal challenge. Taken together, these findings show that EVs play a role in protection against fungal infection, although they induce a partial pro-inflammatory response.