Immunohistochemical study with an anti-myelin serum. A marker for all glial cells except 'dark' oligodendrocytes.

ABSTRACT

The usefulness of an anti-myelin antiserum as a possible marker for glial cells and related structures was investigated using rat brain. As expected, the myelin fibers were heavily stained but the neuronal cells and their processes were unreactive. The oligodendrocytes, identified on electron microscopy, revealed labelling of only the light and medium types, but not the dark cells. These results indicate that the suggested morphological classification of oligodendrocytes may be based on varying amounts of myelin antigen synthesis. Astrocytes from all areas, Golgi epithelial cells, Bergmann fibers and some subependymal cells also reacted with this anti-myelin antiserum but the staining was abolished completely by preabsorption with kidney powder. In contrast, the myelin fibers and the light and medium oligodendrocytes could still be labelled. We conclude that this anti-myelin antiserum should prove useful in studies of oligodendrocytes in the central nervous system.