IL6 and transient ischemic attack: Days after the primary stroke and transient ischemic attack, more circulating immune cells (monocytes/macrophages and T lymphocytes) enter the brain parenchyma, and along with local microglia, release a large number of inflammatory factors, such as tumor necrosis factor α (TNF-α), interleukin 1-β (IL-1β), and interleukin 6 (IL-6), which cause serious inflammatory damage to the glia and neurons, ultimately leading to neuronal apoptosis and necrosis (Wang et al., 2021b; Qiu et al., 2021).