Interleukin 23

Interleukin 23

Crystal structure of IL-12, a cytokine related to IL-23

Interleukin 23 (IL-23) is a cytokine that plays a crucial role in the immune system. It is involved in the inflammatory response and is important in the pathogenesis of several autoimmune diseases. IL-23 is a member of the IL-12 cytokine family and shares a common subunit with IL-12.

Structure

IL-23 is a heterodimeric cytokine composed of two subunits: the p19 subunit, which is unique to IL-23, and the p40 subunit, which is shared with IL-12. The p40 subunit is encoded by the IL12B gene. The structure of IL-23 allows it to bind to its specific receptor, the IL-23 receptor, which is expressed on the surface of certain immune cells.

Function

IL-23 is primarily produced by dendritic cells and macrophages. It plays a key role in the differentiation and maintenance of T helper 17 cells (Th17 cells), which are a subset of T cells involved in the immune response against extracellular pathogens and in the development of autoimmune diseases. IL-23 promotes the production of pro-inflammatory cytokines such as IL-17 and IL-22, which contribute to inflammation and tissue damage in autoimmune conditions.

Role in Disease

IL-23 has been implicated in the pathogenesis of several autoimmune diseases, including psoriasis, rheumatoid arthritis, inflammatory bowel disease, and multiple sclerosis. In these conditions, IL-23 drives the inflammatory response by promoting the expansion and activation of Th17 cells, leading to chronic inflammation and tissue damage.

Therapeutic Target

Due to its role in autoimmune diseases, IL-23 is a target for therapeutic intervention. Several biologic drugs have been developed to inhibit IL-23 signaling, including monoclonal antibodies that specifically target the p19 subunit of IL-23. These therapies have shown efficacy in treating conditions such as psoriasis and Crohn's disease by reducing inflammation and improving clinical symptoms.

Related pages

• Cytokine
• IL-12
• T helper 17 cells
• Autoimmune disease