Date : 2012. 3 . 29, 5:00 PM Place : Mogam Hall, Bldg.500 -Abstract- Communication between cells and environment is an essential process in living organisms. The secretion of exosomes (extracellular vesicles) is a universal cellular process occurring from simple organisms to complex multicellular organisms, including humans. Throughout evolution, both prokaryotic and eukaryotic cells have adapted to manipulate exosomes for intercellular communication via outer membrane vesicles in the case of Gram-negative bacteria and microvesicles or exosomes in eukaryotic cells. Although recent progress in this area has revealed that exosomes play multiple roles in intercellular and interspecies communication, the formation and the pathophysiological roles of exosomes are not understood. This presentation focuses on the comprehensive aspects of mammalian and bacterial exosomes including components, biogenesis, and diverse functions that should facilitate further applications, especially to develop diagnostic tools, therapeutics and vaccines. Taken together with previously reported results, our observations suggest that exosomes are nanocosmos and may act as communicasomes, i.e., extracellular organelles that play diverse roles in intercellular communication.