FIGURE 1.

The structure of exosomes derived from bone marrow mesenchymal stem cells. Membrane-driven endocytosis forms intracellular vesicles in the cytoplasm and stores substances from extracellular fluid in the vesicles. As intracellular vesicles mature gradually in the cytoplasm, intracellular vesicles continue to form inside the vesicles. Intracellular vesicles can store substances in the cytoplasm and form MVB. Finally, MVB fused with the cell membrane and released the intracavinal vesicles, which completed the release of exosomes. In this process, if MVB is directly fused with lysosomes in the cytoplasm, polycysts will be degraded.