CCL17 and Alzheimer disease: Overall and across the stratum corneum, AD skin as compared to control skin displayed increased expression of cytokines involved in innate immunity (IL-18, CXCL8, IL-1β, TNF-α), Th1- (CXCL10), Th2-signaling (CCL17, CCL22, CCL27, TSLP) and angiogenesis (VEGFA) paralleled by a decreased expression of IL-1α.