IL17A and psoriasis: There are several mechanisms with intricate casting in psoriasis induction by which IL-17 exerts its action on immune cells, keratinocytes, and fibroblasts, inducing the release of inflammatory mediators, including cytokines, IL-6, IL-1β, TNF, and granulocyte–macrophage colony-stimulating factor (GM-CSF), chemokines (CXCL1, CXCL2, CCL20, and CXCL8), matrix metalloproteinases (MMPs), antimicrobial peptides (AMPs; LL37, S100s, β-defensin), and complements [137,138,139].