Fig. 2

Characterization of purified exosomes. a A schematic diagram of the experimental design. Exosomes isolated from sera of the donor mice were injected to the recipient mice via tail-vein. Serum and brain of the donor mice were used for exosomal inflammatory microRNA detection and immunofluorescent staining of microglia/astrocyte marker, respectively. Whole blood, serum, liver, and brain were collected from the recipient mice 24 h after injection. Whole blood, liver, and brain tissues were used for examining the mRNA expression of pro-inflammatory cytokines (such as TNF-α and IL-6) by qRT-PCR. TNF-α concentrations were measured by ELISA in serum, liver and brain homogenates. b Representative western blot image showing enriched TSG101 expression in the exosomal preparation. Sup supernatant, EXO exosomal preparation, WCL whole cell lysate. c Protein concentrations of exosomes in the sera from mice treated with LPS were not altered. n = 3–5 per group. d Endotoxin levels in exosome suspension or serum from PBS- or LPS-treated mice. Sera were collected from mice 1, 4, or 24 h after LPS i.p. injection. n = 3–4 per group. e Zeta potential of exosomes purified from the sera of mice treated for 6 h with PBS or 10 mg/kg LPS either by ExoQuick kit (ExoQuick™) or by differential ultracentrifugation (UC), n = 3 per group. f Percentage of exosomes in the size range of 10–200 nm. g Average exosome size. Data represent mean ± SEM; ns no statistical significance, *P < 0.05, ***P < 0.001, ^###P < 0.001 as compared to the PBS24h-serum group