Pentraxin 3 Released from Neutrophils Increases Plasma Levels in Patients with Acute Coronary Syndrome

Background. Our recently developed ELISA system for the detection of human pentraxin 3 (PTX3) in plasma has demonstrated that plasma PTX3 levels are increased in patients with unstable angina pectoris. However, the origin of the PTX3 from the ruptured plaque or a systemic process and which cells release PTX3 remain unclear. Methods. Blood samples were taken using an aspiration catheter from the site of the ruptured plaque and from the aorta during acute coronary interventions in 118 patients with acute coronary syndrome. These samples were analyzed for PTX3, and brain natriuretic peptide (BNP) was used as a control. Aspirated thrombi from patients with acute myocardial infarction (AMI) (n = 32) were examined by histological staining. Results. Plasma PTX3 levels were higher in blood samples taken from the site of plaque rupture compared to samples taken from the aorta (5.61±1.91 ng/mL versus 4.72 ± 5.61 ng/mL, ?<0.05). On the other hand, BNP levels, as reference, were not different between the samples (P = 0.45). PTX3-positive neutrophils accounted for 70.4% of cells in harvested thrombi, with the remaining cells consisting of mononuclear cells. Conclusions. Infiltrating neutrophils in thrombi at the plaque rupture site are a diagnostically important source of PTX3 in patients with acute coronary syndrome.