Exosomes

It is widely accepted that in most multicellular organisms, cells can communicate with each other using extra-cellular secreted molecules, such as lipids, nucleotides, proteins, or short peptides. These molecules are released into the extracellular space by the cells, and then bind to their receptors on other cells and induce intra-cellular signaling, in order to alter the physiological state of the recipient cells. Moreover, eukaryotic cells release particular types of membrane vesicles into their extra-cellular environment. These vesicles contain a variety of molecules, such as lipids or proteins, and even nucleic acids. These molecules can influence the recipient cells, which take up the vesicles in a complex manner. In the blood the vesicles were known as micro-particles, and in seminal fluid they have been called prostasomes, while the general term of exosomes or extracellular vesicles (EVs) is now becoming common. These membrane vesicles can be specific to the organs from which they originate, or else can just contain cell debris or markers of cell death [1]. The potential role of EVs as intercellular messengers is a scientific hypothesis that has attracted much attention during recent years [2].