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

Figure 1

Characterization of SF-derived EVs isolated by Exoquick polymer precipitation. (a) Particle concentration was quantified measuring the enzymatic activity of the exosomal AChE enzyme by Exocet kit or tracking the particles’ Brownian motion by Nanosight NTA. Columns, mean; bars, SD. (b) A representative particle size profiling by NTA is shown. (c) SF-derived EVs were lysed, and 25 μg of protein was separated in 15% SDS-PAGE gel under reducing condition. The gel was western blotted onto nitrocellulose membranes and stained with antibodies recognizing exosomal marker proteins CD9, CD63, CD81, and TSG101. (d) EVs were embedded into 4 μm beads coated with anti-CD63 and then stained with specific monoclonal antibody for CD7, CD9, and CD81 and analysed by flow cytometry. The antibodies (green peak) were compared with their appropriate isotype control (red peak). Cytometry histograms are shown as one representative experiment. The histograms represent the percentages of CD7-, CD9-, and CD81-positive beads. Columns, mean; bars, SD.

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