MIF (macrophage migration inhibitory factor) was one of the first cytokine activities to be discovered and was initially described as a T cell-derived factor that inhibit the random migration of macrophages1. Recently, MIF was rediscovered as a pituitary hormone that act as the counterregulatory hormone for glucocorticoid action within the immune system2,3. MIF was released from macrophages and T cells in response to physiological concentrations of glucocorticoids. The secreted MIF counter-regulates the immunosuppres-sive effects of steroids on immune cell activation and cytokine production4. MIF plays a critical role in the host control of imflammation and immunity.