IL-36β is synthesized as an inactive precursor and requires proteolytic processing for activation. This processing typically involves the removal of the N-terminal propeptide, which is necessary for the cytokine to become biologically active . The active form of IL-36β binds to the IL-36 receptor (IL-36R), which then recruits the IL-1 receptor accessory protein (IL-1RAcP) to form a signaling complex. This complex activates intracellular signaling pathways, including NF-κB and MAPK, leading to the production of pro-inflammatory cytokines .
IL-36β is primarily expressed in epithelial cells, including keratinocytes in the skin, as well as in various immune cells such as dendritic cells and macrophages . It is upregulated in response to inflammatory stimuli and plays a crucial role in the immune response by promoting the activation and polarization of T cells and dendritic cells .
In the skin, IL-36β contributes to the inflammatory response and is involved in the pathogenesis of several skin disorders, including psoriasis. It enhances the Th17/Th23 axis, which is known to be dysregulated in psoriatic lesions . IL-36β is also expressed in other tissues, such as the lungs, intestines, and joints, where it may play roles in various inflammatory conditions .
The dysregulation of IL-36β has been implicated in several inflammatory diseases. For instance, mutations in the IL-36Ra gene, which encodes the antagonist of IL-36β, are associated with generalized pustular psoriasis, a severe and potentially life-threatening skin condition . Additionally, elevated levels of IL-36β have been observed in psoriatic plaques compared to healthy skin .
Therapeutic strategies targeting IL-36β are being explored for the treatment of inflammatory diseases. Anti-IL-36 antibodies have shown promise in preclinical models of psoriasis, where they attenuate skin inflammation . These findings suggest that IL-36β could be a potential therapeutic target for managing inflammatory conditions.
Recombinant human IL-36β is produced using various expression systems, including E. coli. The recombinant protein is typically purified to high levels of purity and is used in research to study its biological functions and potential therapeutic applications . It is available in both carrier-free and carrier-containing formulations, depending on the intended use .