MIF also known as Macrophage migration inhibitory factor. MIF has been identified to be secreted by the pituitary gland and the monocyte/macrophage and to play an important role in endotoxic shock. MIF has the unique property of being released from macrophages and T cells in response to physiological concentrations of glucocorticoids. The secretion of MIF is tightly regulated and decreases at high, anti-inflammatory steroid concentration. Recombinant human MIF, fused to GST-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.