From Mitochondria to Immunity: The Emerging Roles of Mitochondria‐Derived Vesicles and Small Extracellular Vesicles in Cellular Communication and Disease

ABSTRACT According to the endosymbiotic theory of mitochondrial origin, an α‐proteobacterium entered a prokaryotic cell and, through symbiosis, evolved into the mitochondria—the powerhouse of the cell. Like other bacteria, the α‐proteobacteria generate their own extracellular vesicles (EVs), a trait that was passed onto the mitochondria, enabling them to generate mitochondria‐derived vesicles (MDVs). MDVs, similar to small EVs (sEVs), are vesicles ranging from 30 to 200 nm in diameter and carry cargo for degradation by lysosomes and peroxisomes. MDVs share several features with sEVs, including targeted cargo degradation, biogenesis, packaging into multivesicular bodies, nucleic acid and protein transportation, induction of immune responses, and surface antigen presentation. MDVs may also be released from the cell in a manner similar to sEVs, potentially influencing intercellular communication and immune responses. Furthermore, the presence of MDVs presents opportunities for early disease detection, including neurodegenerative disorders and cancer. In this review, we explore the differences and similarities between MDVs and EVs, including their roles in immunity.