Western blotting was carried out as previously described.15 (link) Cell or EV lysates were prepared in lysate RIPA buffer (Thermo Fisher Scientific), to which a cocktail of protease inhibitor was added (Sigma-Aldrich Co., St Louis, MO, USA). An equal amount of protein was loaded and run on a 10% SDS-PAGE gel. The proteins were moved from the gel to a PVDF membrane (Merck Millipore, Billerica, MA, USA) and probed, first, with the primary, and followed by HRP-conjugated secondary antibody. The signals were detected using a chemiluminescence detection system (GE Healthcare, Chicago, IL, USA), according to the manufacturer’s protocol. Primary antibodies used: anti-mouse-NIS (Thermo Fisher Scientific; dilution: 1:2,500), anti-rabbit-CD63 (Abcam, Cambridge, UK; dilution: 1:2,000), anti-rabbit-GM130 (Abcam; dilution: 1:3,000), anti-mouse-GAPDH (Santa Cruz Biotechnology Inc., Dallas, TX, USA; dilution: 1:5,000) and anti-rabbit-β-actin (Cell Signaling Technology, Danvers, MA, USA; dilution: 1:5,000). HRP-conjugated anti-rabbit (Cell Signaling Technology; dilution: 1:5,000) and anti-mouse (Cell Signaling Technology; dilution: 1:5,000) secondary antibodies.