Figure 2.
Characterization of serum-derived exosomes. Exosomes were purified from 100 μL serum. (A) Exosomal protein CD9, CD63, Flottin-1 and the expression of PD-1 and PD-L1 on exosomes were verified by western blotting. (B) Exosomes isolated from serum were observed under electron microscopy (TEM) with 50–150 nm in diameter. Scale bar: 100 nm. (C) Concentration and size distribution of exosomes were analyzed by NanoSight. (D) Flow Cytometry was performed for the exosomes surface protein CD9, CD63 and exosomal PD-1, exosomal PD-L1 detection.