No abstract

Microvesicles or MVs released from the plasma membrane of eukaryotic cells, during early apoptosis, are 100-1000 nm in diameter, rich in phosphatidylserine and important mediators of intercellular communication. Analysis of MVs revealed two distinct subtypes that can be collected from cells in culture: cMVs are constitutively released and sMVs that are stimulated for release. There are marked differences in size and composition between cMVs and sMVs, the former being smaller, denser, ‘well made’ and more slowly released from cells whereas sMVs are larger, lighter, less robust and released rapidly in response to a stress stimuli. Furthermore these differences allude to different physiological roles, indeed, analysis of calcium homeostasis having revealed MVs to contain high calcium levels, that are deliverable to cells. The implications of this research highlights that detailed characterisations of MVs should be performed to further understand the underlying mechanisms in MV biology, as the subtypes are generated through different processes and undoubtedly will perform different roles.