The prothrombotic potential of platelet factor 4

Heparin-induced thrombocytopenia (HIT) is a prothrombotic disorder initiated by heparin administration It is caused by the formation of pathogenic antibodies to complexes of platelet factor-4 (PM) and heparin on platelet surfaces that cause platelet activation, aggregation and thrombosis There has been intense research on this intriguing, drug-related thrombocytopenia explaining several characteristic aspects of this condition However. pi thrombotic potential of the key player, PF4 has not been investigated in many studies although it has been shown to be critical in monocyte chemotaxis, monocyte-platelet interaction, and megakaryocyte suppression. all of which can contribute to the pathophysiology of HIT This article explains the important role of PF4 released during platelet activation with the administration of heparin in the pathogenesis of thrombocytopenia and thrombosis in HIT. (C) 2009 European Federation of Internal Medicine Published by Elsevier B V All rights reserved