Prednisone is an adrenocortical steroid that suppresses immune reactivity by its actions on several immunocompetent cells, particularly macrophages and T lymphocytes.
It interferes with macrophage function by inhibiting action of the macrophage migration-inhibition factor (MIF) and of  -interferon (IFN-) on macrophages.
It interferes with T lymphocyte function by:
-	inhibiting synthesis and release of interleukin-1 (IL-1) and tumor necrosis factor (TNF) by activated macrophages (and thus inhibiting activation of T lymphocytes)
-	inhibiting expression of the interleukin-2 (IL2) gene (and thus interaction of IL-2 with its receptor on T cells and activation of T lymphocytes)
-	inhibiting generation of cytotoxic T lymphocytes