Human Interleukin 37 (IL37) Protein

Background

IL37 is a unique member of the IL-1 family that functions as an anti-inflammatory cytokine by suppressing immune activation and limiting excessive inflammation. IL37 is synthesized as a precursor that translocates to the nucleus or binds to the IL-18 receptor alpha chain (IL18Rα) and IL1R8 (SIGIRR), leading to inhibition of NF-κB, MAPK, and inflammatory cytokine production. It is expressed in epithelial cells, monocytes, and dendritic cells, particularly during inflammatory and infectious conditions. IL37 acts as a master suppressor of inflammation by reducing pro-inflammatory cytokine levels, chemokine production, and immune cell activation. It plays a protective role in autoimmune diseases, cardiovascular diseases, and metabolic disorders, where its overexpression reduces inflammation and tissue damage. Dysregulation of IL37 is linked to chronic inflammatory diseases such as rheumatoid arthritis, lupus, and colitis. Knockdown studies demonstrate exacerbated inflammation, increased cytokine production, and tissue pathology, highlighting IL37's role as a crucial anti-inflammatory mediator and immune regulator in maintaining tissue homeostasis and controlling immune responses.