[Cellular microparticles and blood-vessel damage. I. Structure, detection and origin]

In virtually all eukaryotic cells, activation and apoptosis lead to the formation of vesicles or microparticles by intracellular mechanisms which as yet are not completely understood. Flow cytometry, electron microscopy and ELISA techniques can be used to detect microparticles. Microparticles are a heterogeneous population and their numbers, cellular origin, composition and functional characteristics, both in vitro and in vivo, depend on the circumstances under which they were generated. Microparticles derived from various cells, primarily platelets but also lymphocytes, granulocytes, monocytes, erythrocytes and endothelial cells, are present in the circulation of healthy subjects. Elevated numbers of microparticles can be found in a wide variety of diseases, all of which are associated with hypercoagulability and blood-vessel damage, thus suggesting their role in the pathogenesis of vascular disease.