THE FEATURES OF THE EXPRESSION OF IBA1 PROTEIN ON THE MICROGLIAL CELLS OF THE SPINAL CORD OF MICE WITH THE EXPERIMENTAL ALLERGIC ENCEPHALOMYELITIS AS A MODEL OF THE MULTIPLE SCLEROSIS

Multiple sclerosis (MS) is the most common autoimmune disease of the central nervous system (CNS). Experimental autoimmune encephalomyelitis (EAE) is its widely used corresponding animal model. MS/EAE pathology are substantially modulated by microglia, the resident immune competent cells of the CNS. The aim - on acute and chronic form of EAE in mice, to study the dynamics of changes in the microglial population of the spinal cord by immunofluorescence analysis. We used activated microglia marker Iba1⁺ to characterize distribution of microglia/macrophages in spinal cord of normal mice and mice with acute and chronic model of EAE. We found that Iba1⁺ cells with morphology of resting microglia equally distributed in the normal spinal cord of control mice. In contrast to controls, microglia activation was more pronounced in the grey matter of acute spinal cords compare to the white matter. Amoeboid microglial cells formed some form of aggregations in the gray matter - «conglomerates», presumably attacking other cells of the spinal cord. In chronic spinal cord, we observed different pattern of distribution of microglial population - the cells localized in the white matter, presumably in the sites of demyelination. Hereby, in spinal cord of mice with acute form of EAE, activation and proliferation of microglial cells take place, mainly in the gray matter. The amount of activated microglia decreases in the chronic stage of the EAE with localization in the areas of demyelination in the white matter. The obtained results indicate that the morphological-functional changes in the microglial cells of the mouse spinal cord under the conditions of development of the EAE and the dynamics of the microglia responses under these conditions might determine the phenomenology of pathophysiological processes in the EAE. Hence, understanding microglia involvement in MS offers new promising paths for therapeutic intervention.

Iba1⁺-клетки , microglia, experimental allergic encephalomyelitis, spinal cord, Iba1⁺-cells

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