Concerning the pro-inflammatory cytokines, keratinocyte stimulation with α-type PSMs resulted in enhanced expression of IL-6, TNF-α as well as IL-1 family cytokines (IL-1β and IL-36γ), which are known to be overexpressed in skin from AD patients and regulate chemokine expression in keratinocytes [55,56,63]. Here, IL6 is linked to Alzheimer disease.