TRANSPLANTATION OF OLIGODENDROCYTE PRECURSORS IN THE ADULT DEMYELINATED SPINAL-CORD - MIGRATION AND REMYELINATION

A demyelinating lesion induced by an injection of lysolecithin into th e spinal cord can be partly repaired by oligodendrocyte precursors tra nsplanted at a distance of 6-8 mm from the lesion. Using a non-toxic f luorescent dye (Hoechst 33342) as a cell marker, we demonstrate that t ransplanted oligodendrocyte precursors from different origins (periven tricular zone fragments from newborn mouse and cultured rat oligodendr ocyte progenitor cells) can migrate along specific pathways (i.e. whit e matter fasciculi, ependymal wall, meninges and blood vessels). These cells can be attracted when passing at the vicinity of the lesion as well as differentiate and remyelinate axons with the lesion. Myelin re pair thus appears to be the result of distinct successive events: migr ation, specific attraction, differentiation and myelination. This can occur in both shiverer and normal adult hosts.