Blood collection and separation of neutrophils
Venous blood samples (10 ml) obtained from the patients with ischemic
stroke and healthy controls were collected in ethylene diamine
tetraacetic acid anticoagulant vacuum tubes at admission. Blood samples
were fractionated through centrifugation at 3000 × g for 10 min at 4°C.
Next, the plasma layer was aliquoted and stored at -80°C for routine lab
assays. Neutrophils were separated using a standard Ficoll‐Paque Plus
gradient method for RNA extraction and examination as previously
described(G. Li, Ma, et al., 2018).