IL4 and Alzheimer disease: Th2 cytokines reduce expression of important skin barrier proteins: filaggrin, loricrin and involucrin.97, 98 The expression of fibronectin is increased by IL‐4 and may facilitate S. aureus adherence in AD.99 The failure to mount an appropriate AMP response in AD may also be due to the suppressive effects of IL‐4 and IL‐13, and may enhance S. aureus colonization further.12, 13, 100