Specific inhibition of macrophage migration inhibition factor by fucosylated glycolipid RM

The effects of glycolipids on the interaction of the MIF (migration inhibition factor) with rat macrophages were examined using a migration inhibition assay system. MIF activity was specifically blocked by fucosylated Glycolipid RM [Gal alpha 1-3Gal(2-1 alpha Fuc) beta 1-3GalNAc beta 1-3Gal beta 1-4Glc beta 1-1ceramide, (1978) J. Biochem. 83, 85-90], but not by Cytolipin R, hematoside, or blood group B active glycolipid [Gal alpha 1-3Gal(2-1 alpha Fuc) beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc beta 1-1ceramide]. Inhibition of MIF activity was proportional to the concentration of Glycolipid RM. These findings suggest that Glycolipid RM acts as a receptor for MIF.