The significance of circulating microparticles in physiology, inflamatory and thrombotic diseases

Background. - In multicellular organisms, apoptosis and subsequent microparticle shedding play a key role in homeostasis. Having long been considered as "cellular dust", microparticles released in biological fluids upon cell activation or apoptosis appear as multifunctionnal bioeffectors involved in the modulation of key functions including immunity, inflammation, hemostasis and thrombosis, angiogenesis. MP constitute reliable markers of vascular damage, accessible to biological detection whilst the cells they originate from remain sequestered in tissues or are promptly submitted to phagocytosis. Recent findings. - MP modulate biological functions of target cells through the transfer of cytoplasmic content, lipids and membrane receptors. The pharmacological modulation of circulating levels of microparticles could be of particular interest in thrombotic or inflammatory diseases, cancer or hemophilia. Conclusion. - MP can now be viewed not only as a hallmark of cell damage but also as a true biological tool. (c) 2005 Elsevier SAS. Tous droits reserves.