Fig. 1. Brief structure of clinical application of exosomes.

Exosomes are produced by almost all living cells, mainly immune cells (including macrophages, NK cells, dendritic cells, T cells, B cells, etc.) and tumor cells. The cargo of exosomes can be roughly divided into proteins, lipids, nucleic acids, and metabolites. The cellular membranes contain specific surface adhesion proteins, vector ligands (CD11b, CD18 receptors, integrins, glycoproteins, tetraspanins, etc.), and MHC. After specific modification, exosomes could promisingly assist tumor diagnosis and treatment as drug delivery systems, cancer vaccines, and liquid biopsy biomarkers. (By Figdraw).