Characterization of the Proinflammatory Profile of Synovial Fluid-Derived Exosomes of Patients with Osteoarthritis

Figure 2

Characterization of SF-derived exosomes isolated by immunoaffinity. (a) SF-derived exosomes isolated by Exoquick polymer precipitation or immunoaffinity magnetic beads were assessed for immune complex contamination by immunofixation. The immunofixation gel is shown as one representative experiment. The particle concentration (b) and size (d) were quantified tracking the particles’ Brownian motion by Nanosight NTA. Columns, mean; bars, SD, significant difference . (c) A representative particle size profiling by NTA is shown. (e) SF-derived exosomes were lysed, and 2 μg of protein was separated in 15% SDS-PAGE gel under reducing condition. The gel was blotted onto nitrocellulose membranes and stained with antibodies against exosomal markers CD9, CD63, CD81, and TSG101. (f) Exosomes were bound by Exo-Flow beads, stained with Exo-FITC, and analysed by flow cytometry. Histograms of one representative experiment are shown. Exosome-bound beads (red peak) were compared with beads alone (white peak).

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