IL13 and Alzheimer disease: Cytokines interleukin (IL)-4 and IL-13 [17] are also linked with AD, as they mediate Type 2 inflammation, the distinctive immune response whereby T-helper 2 (Th2) cells orchestrate an allergic cascade, prompting the recruitment of eosinophils, mast cells, and other immune effectors; the heightened Type 2 immune response contributes to the characteristic features of skin inflammation, pruritus, and compromised barrier function of AD.