OLIGODENDROCYTE PRECURSORS SURVIVE POORLY AND DO NOT MIGRATE FOLLOWING TRANSPLANTATION INTO THE NORMAL ADULT CENTRAL-NERVOUS-SYSTEM

Cell cultures enriched for oligodendrocyte precursors were prepared fo r male neonatal rat pups and transplanted into the spinal cord white m atter of normal and x-irradiated syngeneic adult female rats. Transpla nted cells were detected using a probe specific for the rat Y chromoso me immediately after transplantation and 14 days later. In non-x-irrad iated tissue, significantly fewer cells were seen at 14 days compared with time zero, and no cell migration was observed. In x-irradiated ti ssue, cells both survived and migrated into the surrounding grey and w hite matter. The observed behaviour of oligodendrocyte precursors in n ormal adult tissue is in contrast to their behaviour in myelin mutants and neonates, where migration and survival have been well documented (Warrington et al., 1993; Lachapelle et al., 1994), but mimics the beh aviour of the O-2A progenitor-like cell line, CG4, following transplan tation into similar environments (Franklin et al., 1996). The findings in this study have profound implications for the use of grafts of oli godendrocyte precursors as a therapy in human demyelinating diseases, because they indicate that grafts will need to be introduced directly into each clinically relevant area of demyelination. (C) 1997 Wiley-Li ss, Inc.