fig1

Figure 1. Structure and composition of exosome. Exosome is a lipid bilayer structure that contains lipids, proteins and nucleic acids. Sphingomyelin, phosphatidylserine, cholesterol and ceramides are highly distributed on the membrane. In addition, exosomes also contain a variety of proteins such as major histocompatibility complex I and II (MHCI and MHCII), tetraspanins (CD9,CD63,CD81), endosomal origin proteins (ALIX,Tsg101), heat shock proteins (HSP70,HSP90), enzymes(GAPDH, nitric oxide synthase, catalase), receptor(EGFR), adhesion proteins, integrins, cytoskeleton proteins (actin, gelsolin, myosin, tubulin) and cytosolic proteins, as well as RNA, miRNA and DNA.