Interleukin 20

Abstract

IL-20 is a member of the IL-10 family of cytokines that also includes IL-10, , and IL-26 as well as a number of viral homologs. Keratinocytes and monocytes in states of activation can produce IL-20. It transmits signals via two different cell-surface receptor complexes resulting in the activation of STAT3 in keratinocytes and other epithelial cells. Thus it appears to be primarily an inducible autocrine and paracrine factor that regulates proliferation and differentiation of keratinocytes in the context of inflammation. Several findings indicate that IL-20 mediates the hyperproliferation of keratinocytes associated with cutaneous inflammation. As such it is likely to have a central role in inflammatory skin diseases such as psoriasis and eczema. IL-20 also promotes the expansion of multipotential hematopoietic progenitor cells indicating a role beyond the response of epithelial cells to inflammation. Increased understanding of the biology of IL-20 may provide novel opportunities for diagnostic methods and therapeutic intervention.

Luteolin Prevents Solar Radiation-Induced Matrix Metalloproteinase-1 Activation in Human Fibroblasts: A Role for p38 Mitogen-Activated Protein Kinase and Interleukin-20 Released from Keratinocytes

“…In several pathological conditions, including cutaneous inflammation, psoriasis, and eczema, the expression of IL-20 is dramatically increased, so that the IL-20 system may be a useful target for therapeutic intervention. 39 As we have shown here, luteolin may be such a candidate because it reduces the SSR-induced release of IL-20 in keratinocytes, eventually reducing MMP-1 production in fibroblasts that are treated with such a conditioned keratinocyte medium. Neutralizing IL-20 antibodies also reduced MMP-1 production, but the effect was less pronounced compared to the p38 MAPK inhibitor, indicating that several p38 MAPK-dependent cytokines are involved in MMP-1 upregulation in fibroblasts, as suggested by Dong and colleagues.…”