IL-2 (interleukin-2) expression is known to reduce with age and results in influenza infection, neoplasms and lethal autoimmunity. IL-2 participates in T cell proliferation and differentiation and controls the homeostasis of T cell. As a part of immune response, IL-2 stimulates the action of T helper cell 1 and 2 cells and endothelial white blood cells of skeletal muscles. IL-2 regulation is controlled by c-rel protein. IL-2 is a neurotrophic molecule and has special functions in cortical, hippocampal, septal, cerebellar and retinal neurons.
