%0 Journal Article %A Tommaso Neri %A Federica Rota %A Silvia Petrini %A Yuri Carmazzi %A Cristina Balia %A Valentina Scalise %A Roberto Pedrinelli %A Valentina Bollati %A Alessandro Celi %T Particulate matter induces the expression of procoagulant microparticles by human monocytic cells %D 2014 %J European Respiratory Journal %P P1468 %V 44 %N Suppl 58 %X Background: Cell derived microparticles (MP), ranging in size between 0.05 and 1 μm, are phospholipid vesicles involved in blood coagulation and inflammation. Cell activation and apoptosis can lead to MP formation; while the mechanisms that lead to MP formation are not completely elucidated, intracellular calcium mobilization is known to be involved. Particulate matter (PM) is a mixture of solid and liquid particles suspended in the air, originated from a variety of sources. Exposure to PM has been associated with increased cardiopulmonary morbidity and mortality. The observation that PM induces cytosolic calcium mobilization is consistent with the hypothesis that PM induces the generation of MP.Aim: To investigate whether PM induces the generation of procoagulant MP by the human monocytic cell line,THP-1.Methods: THP-1 were incubated with PM. PM treatments were performed using SRM1648a (Standard Reference Material,National Institute of Standards and Technology).The presence of MP was evaluated through a prothrombinase assay; MP-associated tissue factor activity was assessed by a onestage clotting assay.Resuts: 1h PM treatment induces a dose-dependent increase in MP generation and 4h treatment induces an increase of MP-associated tissue factor activity (fig 1 a,b).Conclusions:PM-mediated generation of procoagulant MP might help to understand the possible correlation between PM exposure and cardiopulmonary diseases. %U