Data from: Extracellular vesicles produced by the probiotic Propionibacterium freudenreichii CIRM-BIA 129 mitigate inflammation by modulating the NF-κB pathway

Extracellular vesicles (EVs) are nanometric spherical structures implicated in intercellular communication, whose occurrence is considered a general occurring-phenomenon in living organisms. Bacterial EVs have been associated to several processes, including survival, competition, pathogenesis and immunomodulation. Among probiotic Gram-positive bacteria, some Propionibacterium freudenreichii strains were reported to present anti-inflammatory activity, due to proteins such as surface-layer protein B (SlpB). We hypothesized that beyond surface exposure and secretion, P. freudenreichii could export immunomodulatory proteins packed inside EVs to mediate the interaction with the host. In order to demonstrate EVs production in this species, we employed size exclusion chromatography for their purification from concentrated supernatants derived from milk ultrafiltrate (UF) culture medium. EVs physicochemical characterization was performed with transmission electron microscopy and nanoparticle tracking analysis, showing typical shape and sizes. Proteomics characterization of EVs protein content was carried out on a Qexactive coupled to NanoLiquid Chromatography.