FIGURE 1.

Characterization of exosomes. A, whole cell lysates and exosomes were subjected to Western blot analysis with antibodies against the proteins indicated. B, exosomes were treated with 0.25% trypsin ± 0.1% saponin before Western blotting with antibodies against α-syn, GAPDH (cytosolic protein), and Alix (membrane protein). C, relative levels of α-syn in cell lysates compared with that secreted, either free or in exosomes, was analyzed by Western blotting. Cell lysate represents 1% of total cells; media (−exosomes) represents 10% of culture medium TCA-precipitated after exosome isolation, and 50% of total exosomes isolated were loaded. D, dynamic light scattering of exosomes from N2a cells with or without overexpressing-type α-syn shows vesicles of around 100 nm in diameter (analyzed by number). E, isolated exosomes from N2a cells (blue) or N2a cells overexpressing wild-type α-syn (red) were analyzed by NanoSight nanotracking analysis.