Presence of macrophage migration inhibitory factor (MIF) in ependyma, astrocytes and neurons in the bovine brain

We investigated the immunohistochemical localization of a cytokine macrophage migration inhibitory factor (MIF) in the bovine brain. MIF was present in the ependymal cell linings of the cerebral ventricles throughout. Double immunostaining of the section with anti-glial fibrillary acidic protein (GFAP) antibody and with anti-MIF antibody showed that the astrocytes present in subependymal layer were immunoreactive for MIF. In the hippocampus, the pyramidal cells in the CA3 and CA4 subfields and the granule cells of the dentate gyms were immunoreactive. The bundles of messy fibers were stained along their projections to CA3 and CA4 regions. The nuclei of the subpopulation of these MIF-immunoreactive cells were also immunostained. These results indicated the widespread distribution of a cytokine, MIF, in the bovine brain and suggested the possibility that MIF might play additional roles than a proinflammatory mediator role in the brain.