Extracellular vesicles in infectious diseases - importance and perspectives

Extracellular vesicles (EVs) are mother cell derived transport units released into the extracellular environment. They are a new pillar of intercellular communication as they carry nucleic acids, proteins, and other signalling molecules, protecting them from degradation in the extracellular environment until fusion of the vesicle with the target cell. The transport mechanism relies on surface structures involved in cell adhesion. It is well known that all cellular organisms are capable of producing EVs. Most human cells have this capability, and EVs can be detected in all body compartments. At the time of their discovery, EVs were considered as useless waste vesicles of marginal interest. Thanks to the newly described transport mechanisms of biologically active molecules, EVs are currently known to participate in a variety of homeostatic mechanisms. In infectious diseases, the most studied area is the modulation of the immune response, where they are seen as potential biomarkers, as their production or the content they carry can be altered under pathological conditions. For microbes, interactions at the pathogen-pathogen and pathogen-host level are at the forefront of attention. EVs also have potential for use as drug delivery systems and novel targets for pharmacotherapy.