IL17A and early-onset autosomal dominant Alzheimer disease: In addition to the immunological disorders described above, emerging evidence suggests that IL-17A secreted by meningeal γδT cells regulates the pathogenesis of Alzheimer's disease (57, 58), IL-17A secreted by Th17 cells is involved in alcohol abuse (59), and IL-17A regulates blood pressure via the activation of paraventricular nucleus neurons (60) (Figure 2B).