TRACING TRANSPLANTED OLIGODENDROCYTES DURING MIGRATION AND MATURATION IN THE SHIVERER MOUSE-BRAIN

Fragments of neural tissue from normal newborn mouse were stained with Hoechst 33342 dye before transplantation into the newborn shiverer mouse brain. Combination of this technique with immunohistochemistry demonstrated that, after transplantation, these cells are able to survive as long as unstained cells and to myelinate in the shiverer mouse host brain. Stained cells express the normal sequence of differentiation in terms of chronology of differentiation marker expression [04, galactocerebroside (GalC), myelin basic protein (MBP)], as normal cell do in situ. It has thus been possible by this technique to show the migration pathways of transplanted cells and to correlate them with the expression of specific markers: long distance migration along white matter axonal pathways occurs when cells are o4-positive, GalC-negative. By contrast, only GalC-positive cells are able to migrate across the grey matter in the absence of radial glia. Finally, it has been possible to propose a migration and differentiation sequence of these cells, suggesting that MBP-positive oligodendrocytes divide after migration in the target zone.