Neutrophil extracellular traps formation is associated with impaired clot retraction and fibrinolysis in asthma.

BACKGROUND

Asthma is associated with an elevated risk of venous thromboembolism and pulmonary embolism; its etiology is not completely understood.

OBJECTIVE

This study was designed to investigate whether the formation of neutrophil extracellular traps (NET) is associated with impaired clot retraction and fibrinolysis in the blood of patients with asthma.

METHODS

Groups of 50 patients with asthma and 40 healthy subjects were enrolled in this study. Clot retraction kinetics were assessed by optical method (using a digital camera); fibrinolysis was recorded by thromboelastometry; NET predictors in plasma or serum-citrullinated histone H3 concentration, myeloperoxidase activity, and cell-free DNA level-were measured by microplate immunoenzymatic, colorimetric, and fluorometric assays, respectively. Spirometry (FEV1 parameter), exhaled NO (FENO), fibrinogen, d-dimers, IgE, and eosinophil, neutrophil, and platelet counts were assessed by standard clinical procedures.

RESULTS

We found the elevated NET predictors in the blood of patients with asthma, which notably correlate with significant inhibition of clot retraction and fibrinolysis compared to the control group. FENO was found to be the most closely correlated with impaired fibrinolysis and clot retraction among all clinical tests.

CONCLUSION

It was concluded that the formation of NET in the blood of patients with asthma is associated with impairment of clot retraction and fibrinolysis, which may contribute to the formation of unstable thrombi. This may partially explain the elevated risk of venous thromboembolism and pulmonary embolism in asthma.