Brustle et al. have reported successful remyelination in both the brain and the spinal chord after transplantation of oligodendrocyte precursors into rats suffering from demyelination.

The proliferation and differentiation of multipotential neural stem cells and precursor glial cells can be controlled by defined factors in the CNS. The team first aggregated the ES cells into embryoid bodies (EBs) and proceeded to expose them to a sequence of media with basic fibroblast growth factor (bFGF), FGF2 and epidermal growth factor (EGF), and FGF2 and platelet-derived growth factor (PDGF). The third combination has been reported to promote proliferation of glial precursor cells. And, as expected, the resulting isomorphous population demonstrated immunoreactivity to a monoclonal antibody for a typical glial precursor epitope. An epitope, or antigenic determinant is a localized region on an antigen's surface, chemically recognized by an antibody (Curtis). Withdrawal of growth factors promoted differentiation into oligodendrocytes and astrocytes. The former were recognized by a multipolar morphology and their immunoreaction to the antibody O4. After five days without growth factors the cells began to express myelin proteins.

Caption: A) Cells grown with FGF2 and PDGF are immunoreactive to the monoclonal antibody A2B5 which recognizes a membrane epitope typically expressed in glial precursors. B) Four days after growth factor withdrawal, many cells assumed the typical multipolar morphology of oligodendrocytes and express the oligodendroglial antigen O4. C) Immunoreactivity confirms the presence of astrocytes as well. (Top images - immunofluorescent, bottom images - phase contrast).