Standardization of pre-analytical variables in plasma microparticle determination: results of the International Society on Thrombosis and Haemostasis SSC Collaborative workshop.

Microparticles (MP) are sub-micron sized vesicles released by activated or apoptotic cells. They are generally defined as 0.1 to 1 μm membrane particles that expose the anionic phospholipid phosphatidylserine (PS) and membrane antigens representative of their cellular origin [1]. It is now well recognized that MP behave as vectors of bioactive molecules, playing a role in blood coagulation, inflammation, cell activation and cancer metastasis. In clinical practice, circulating MP originating from blood and vascular cells are elevated in a variety of prothrombotic and inflammatory disorders, cardiovascular diseases, autoimmune conditions, infectious diseases and cancer [1-3].