The effect of IL-17 cytokines is mediated via the adaptor protein connection to I??B kinase and stress-activated protein kinases (CIKS)/Act1. [48] This is confirmed by the association of psoriasis with the gene encoding CIKS. IL-17A and IL-17F act on keratinocytes to stimulate the production of ??-defensins and antimicrobial peptides (AMPs), and chemokines such as IL-8, CCL20 and CCL2.