Interleukin-16

Interleukin-16 (IL-16) is a cytokine that plays a crucial role in the immune system. It was originally described as a lymphocyte chemoattractant factor. IL-16 is produced by a variety of cells, including lymphocytes, monocytes, and dendritic cells.

Function

IL-16 functions primarily as a chemoattractant for CD4+ T cells, monocytes, and eosinophils. It binds to the CD4 receptor on the surface of these cells, triggering a cascade of intracellular events that lead to cell migration. This cytokine is also involved in the regulation of T cell activation and inflammatory response.

Structure

Interleukin-16 is initially synthesized as a precursor protein, known as pro-IL-16. This precursor is cleaved by caspase-3 to produce the active form of IL-16. The active cytokine is a homotetramer, meaning it consists of four identical subunits.

Clinical Significance

IL-16 has been implicated in various diseases and conditions, including asthma, rheumatoid arthritis, and HIV infection. Elevated levels of IL-16 have been observed in the synovial fluid of patients with rheumatoid arthritis, suggesting a role in the pathogenesis of this autoimmune disease. In the context of HIV, IL-16 may influence the progression of the disease by modulating the immune response.

Research

Ongoing research is exploring the potential of IL-16 as a therapeutic target in inflammatory and autoimmune diseases. Studies are also investigating its role in cancer and neurodegenerative disorders.

See also

• Cytokine
• Immune system
• CD4 receptor

External links

• IL16 gene - NCBI
• UniProt entry for IL16