Immunotherapy, autoimmunity, and interleukin-12

摘要

Interleukin-12 (IL-12), also known as natural killer cell stimulatory factor, is a recently discovered cytokine chiefly produced by activated monocytes/macrophages and other antigen-presenting cells of the immune system. IL-12 has recently been cloned in the dog and cat. It is a heterodimer, composed of two subunits, each encoded by a separate gene. The larger subunit (p40) is 40 kDa and is inducible while the smaller subunit, p35, is constitutively expressed. Apparently, p35 resembles the structureof IL-6 while p40 bears structural similarities to the soluble form of the IL-6 receptor, suggesting that IL-12 has evolved from a cytokine-receptor complex.