Abstract
Background Particulate matter contained in ambient air pollution has been associated with cardiovascular
diseases in several epidemiological studies.
Objective The aim of this study was to investigate the potential for urban particulate matter
to induce changes in clot structure through interaction with vascular endothelial
cells.
Methods We examined the structure of clots formed on human umbilical vascular endothelial
cells that had been treated with various types of particles versus those formed on
untreated cells. Particles used were standard reference particulate matter from diesel
engine emissions (SRM2975) and urban ambient collection (SRM2787).
Results There was a dose-dependent increase in fibre density in clots formed on particle-treated
endothelial cells. It was also found that exposure to the particles induced increased
expression of tissue factor and reduced expression of thrombomodulin genes as measured
by real-time polymerase chain reaction and increased expression of von Willebrand
factor and plasminogen activation inhibitor-1 as measured by ELISA.
Conclusion These changes are consistent with increased procoagulant activity of air pollution
particulate matter–treated endothelial cells and suggest that particulate matter has
the potential to promote clot formation through changes induced in endothelial genes
controlling clot formation.
Keywords
air pollution - fibrin clot structure - thrombosis/coagulation - endothelial cells
