Migration Inhibitory Factor (MIF, Macrophage), human recombinant (rHuMIF)

Macrophage migration inhibitory activity originally identified 30 years ago based on the ability to prevent the migration of guinea pig macrophages out of capillary tubes in vitro. A number of cytokines, including interferon-g and IL-4, exhibit macrophage migration inhibitory activity. A cDNA clone was isolated from a lectin-stimulated T-cell hybridoma cDNA library and reported to encode a protein with macrophage migration inhibitory activity. This protein was referred to as human migration inhibitory factor (MIF). MIF cDNA encodes a 115 amino acid residue polypeptide that lacks conventional hydrophobic leader sequence. MIF is expressed in many tissues and in all cell lines examined to date. MIF was also discovered as a growth factor-induced delayed early response gene DER6. Recently, MIF was reported to be a secreted cytokine that exerts a central and wide ranging role in host inflammatory responses. Evidence for a receptor of this has not been reported. E. coli-expressed MIF lacks macrophage migration inhibitory activity and is recommended for use as a calibrator for MIF immunoassays. Purified recombinant human MIF contains 114 amino acid residues and lacks the N-terminal methionyl group. Recombinant MIF has a predicted molecular mass of approximately 12.5kD. Storage and Stability: Lyophilized powder may be stored at -20°C. Reconstitute with sterile PBS,, > 0.1% BSA or HSA. Aliquot and store at -20°C. Reconstituted product is stable for 3 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.