Vnitr Lek 2010, 56(Suppl 1):112-116

Microparticles

L. Slavík^*, J. Úlehlová, A. Hluší, J. Procházková, M. Procházka, V. Krčová, K. Indrák

Hemato-onkologická klinika Lékařské fakulty UP a FN Olomouc, přednosta prof. MUDr. Karel Indrák, DrSc.

Microparticles (MPs) are particles sized 0.05-1 mm. Their composition varies considerably depending on their origin. On their surface, however, glycoproteins are always found, that are also expressed on the cell surface. This characteristic is used for their detection using monoclonal antibodies. MPs are released as fragments from the plasma membrane of practically all types of eukaryotic cells, either after their stimulation or during apoptosis. MPs may also be formed in the process of cellular tissue damage. Thus, MP formation may represent a wide response to common stimuli in processes such as cellular stress. Endothelial damage and membrane disruption are the key steps in the pathogenesis of inflammation. Methods for detecting MPs result from attempts to determine both their absolute count and their thrombogenic potential. To measure the count of MPs, flow cytometry may be used with success. Recently, numerous methods using a broad spectrum of monoclonal antibodies have been described. At present, platelet MPs are determined by detecting expression of CD41 and endothelial MPs by expression of CD144. By contrast, ELISA methods are used to evaluate the thrombogenic potential of MPs by detecting expression of P-selectin. A specific method is the thrombin generation assay combined with ultrafiltration to assess the thrombogenic potential of MPs. Understanding the role of MPs in the pathology of numerous diseases is primarily based on the knowledge of their pathophysiological properties. The thrombogenic potential is beneficial in thrombocytopenia, with high levels of MPs being detected in patients without bleeding complications. However, this feature may cause thrombotic complications. On the other hand, MPs may play a negative role in myocardial infarction, inflammatory processes or multiple sclerosis.

Keywords: microparticles; trombotic risk factor; P-selektin; flow-cytometry; thrombin generation

Received: March 31, 2010; Published: February 1, 2010  Show citation