Interleukin-17A

Interleukin-17A (IL-17A) is a cytokine that plays a crucial role in host defense against pathogenic organisms and in the development of inflammatory diseases and autoimmune diseases. It is produced by a subset of T cells known as Th17 cells, which are part of the adaptive immune system.

Structure

IL-17A is a member of the Interleukin-17 family, which consists of six members (IL-17A to IL-17F). It is a homodimeric protein, meaning it is composed of two identical subunits. Each subunit is approximately 35 kDa in size.

Function

IL-17A functions primarily as a proinflammatory cytokine, meaning it promotes inflammation. It does this by inducing other cells to produce inflammatory substances such as cytokines and chemokines. This leads to the recruitment of neutrophils, a type of white blood cell, to the site of infection or inflammation.

In addition to its role in inflammation, IL-17A also plays a role in bone metabolism. It stimulates the production of osteoclasts, cells that break down bone tissue, which can lead to bone loss in conditions such as rheumatoid arthritis and periodontitis.

Clinical significance

Due to its role in inflammation and autoimmune diseases, IL-17A is a target for therapeutic intervention. Drugs that block the action of IL-17A, such as secukinumab and ixekizumab, are used to treat conditions such as psoriasis, ankylosing spondylitis, and rheumatoid arthritis.

See also

• Interleukin-17 receptor
• Interleukin-17 family
• Cytokine
• Inflammation
• Autoimmune disease