Figure 1.

Identification and characterization of mast cell-derived exosomes. A. Bone marrow mast cells (BMMCs) show a large number of purple-red granules following toluidine blue staining (400×). CD117 and IgE high affinity receptor (FcεRI) on BMMCs were detected by flow cytometry. B. Mast cell exosomes were isolated through differential centrifugation. Transmission electron micrographs of the isolated exosomes revealed rounded structures with a diameter of approximately 30-150 nm. C. The average size of exosomes was measured by Nanoparticle Tracking analysis (NTA). D. Western blot analysis of the exosomes shows the presence of the exosomal marker proteins TSG101 and CD63. The results show that TSG101 has not significant differences in cells and exosome expression, while CD63 is enriched in exosomes but a little in cell lysates.