IL-8 expression is linked to late onset AD.15 Importantly, IL-8 crosses the blood brain barrier and stimulates the recruitment of immune cells into the brain.16 Aβ causes a 10-fold increase in IL-8 gene expression, and IL-8 is detected in the culture supernatant 2 days after the induction of Aβ (Table 1). This evidence concerns the gene CXCL8 and Alzheimer disease.