Fig. 2

Formation of neutrophil extracellular traps (NETs). A Schema of NET formation. In the process of NET formation, various molecular components such as ROS, PAD4, NE, MPO, and citrullinated histone are involved. Once the membrane is ruptured, the intracellular component is emitted as tangled neutrophil components. This is called a NET. It can be found in any organ and location. Thus, NETs and their accompanied components are involved in neutrophil-gated immune response in multiple organs, including the brain. The image sets represent intravital imaging of NETs in the LPS-induced inflamed mouse brain conducted via two-photon microscopy. B The brain blood vessel was stained with FITC-dextran (green, 70 kDa, 2.5 mg/kg) and SYTOX-orange (red, 5 mM). As SYTOX labels DNA strands not covered with intact membranes, it is possibly used as a NET indicator (red). Scale bar: 50 μm. C NETs are visualized using two different NET-defining markers: SYTOX-orange (red, 5 mM) and neutrophil elastase–Alexa 488 conjugated antibody (green, 0.1 mg/kg). Neutrophil elastase is used as one of the components of the NETs. It is observed as tangled with extDNA stained with SYTOX. Scale bar: 20 μm