Interleukin-6 (IL-6) is a cytokine primarily produced by macrophages. IL-6 plays a major role in acute inflammation. IL-6 also acts indirectly on the hypothalamus to cause fever. The inflammatory effects of IL-6 are involved in the pathogenesis of Giant Cell Arteritis.

Key Points

  • Interleukin-6 (IL-6)
    • Secreted by Macrophages
    • Actions
      • Causes fever
        • Via production of PGE2, which acts on hypothalamic nuclei
      • Promotes inflammation
        • Promotes vasodilation and increased capillary permeability
        • Activates endothelium to enhance leukocyte attachment and migration
      • Involved in pathogenesis of Giant Cell Arteritis (GCA)
        • Tociilizumab is a monoclonal antibody against IL-6 effective in treating GCA