Biogenesis, Biologic Function and Clinical Potential of Exosomes in Different Diseases

Exosomes are extracellular vesicles (EVs) belonging to the nanovesicles family that function as signaling molecules between cells. After their first description in the late 1960s, interest in their potential as a research target has steadily increased. They are small secreted organelles with a single membrane that are well enriched in lipids, proteins, nucleic acids, and glycoconjugates. Exosomes take part in a larger communication network in which cells communicate between one another by DNA shuttling, proteins, RNA, and membrane-bound factors. The machinery of protein quality control occurs through the process termed "exosome biogenesis". Furthermore, the pathway involved in intercellular movement of vesicles is vital in various aspects of human health and diseases. Due to their inherent properties, exosomes are currently being developed as potential therapeutic agents in a wide range of diseases including infectious and non-infectious diseases. Exosomes and other EVs sourced from Mesenchymal stem cells (MSCs) have been shown in different studies to possess therapeutic effects in diverse disease models either in vivo or in vitro. Some mechanisms and/or pathways that MSC-derived exosomes use to illustrate their therapeutic effect against some diseases have also been summarized. This review aims to highlight the recent findings and potential therapeutic application of exosomes in different diseases such as autoimmune, cardiovascular, obesity, neural, soft tissues, bone, and cartilage.