von Willebrand Factor Directly Interacts With DNA From Neutrophil Extracellular Traps

Abstract

Objective—Inflammatory conditions provoke essential processes in the human vascular system. It leads to the formation of ultralarge von Willebrand factor (VWF) fibers, which are immobilized on the endothelial cell surface and transform to highly adhesive strings under shear conditions. Furthermore, leukocytes release a meshwork of DNA (neutrophil extracellular traps) during the process of the recently discovered cell death program NETosis. In the present study, we characterized the interaction between VWF and DNA and possible binding sites to underline the role of VWF in thrombosis and inflammation besides its function in platelet adhesion. Approach and Results—Both functionalized surfaces and intact cell layers of human umbilical vein endothelial cells were perfused with isolated, protein-free DNA or leukocytes from whole blood at distinct shear rates. DNA–VWF interaction was monitored using fluorescence microscopy, ELISA-based assays, molecular dynamics simulations, and electrostatic potential calculations. Isolated DNA, as well as DNA released by stimulated leukocytes, was able to bind to shear-activated, but not inactivated, VWF. However, DNA–VWF binding does not alter VWF degradation by a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13. Moreover, DNA–VWF interaction can be blocked using unfractionated and low-molecular-weight heparin, and DNA–VWF complexes attenuate platelet binding to VWF. These findings were supported using molecular dynamics simulations and electrostatic calculations of the A1- and A2-domains. Conclusions—Our findings suggest that VWF directly binds and immobilizes extracellular DNA released from leukocytes. Therefore, we hypothesize that VWF might act as a linker for leukocyte adhesion to endothelial cells, supporting leukocyte extravasation and inflammation

Pulmonary endothelial activation caused by extracellular histones contributes to neutrophil activation in acute respiratory distress syndrome

“…In addition to being a highly pro-thrombotic protein, vWF is also an important pro-inflammatory mediator, contributing to neutrophil diapedesis via modulating the integrity of the endothelial barrier [31–33]. Additionally, released vWF can directly interact with DNA from neutrophil extracellular traps to aggravate inflammatory damage [34]. This concept highlights the importance of understanding the mechanisms by which inflammatory mediators interact with endothelium.…”

Neutrophil Extracellular Traps Stimulate Proinflammatory Responses in Human Airway Epithelial Cells

“…6 c). Moreover, the anion heparin, which is expected to complete the charge interactions of DNA [44] , was unable to modulate the ability of SN NET to trigger cytokine release by epithelial cells ( Fig. 6 d).…”

Endothelium

“…DNA-bound vWF decreases platelet binding to vWF and might be a linker for leukocyte adhesion to endothelial cells, favoring leukocyte extravasation, and inflammation. 49 Cocaine consumption leads to endothelial dysfunction and accelerated atherosclerosis. Endothelial cells exposed to cocaine or plasma from chronic cocaine consumers were more proadhesive, with increased von Willebrand deposition, enhancing platelet binding, an effect prevented by statin treatment.…”