Generation of dopaminergic neurons in the adult brain from mesencephalic precursor cells labeled with a nestin-GFP transgene

Mesencephalic precursor cells may one day provide dopaminergic neurons for the treatment of Parkinson's disease. However, the generation of dopaminerg ic neurons from mesencephalic precursors has been difficult to follow, part ly because an appropriate means for recognizing mesencephalic ventricular z one precursors has not been available. To visualize and isolate mesencephal ic precursor cells from a mixed population, we used transgenic mice and rat s carrying green fluorescent protein (GFP) cDNA under the control of the ne stin enhancer. nestin-driven GFP was detected in the mesencephalic ventricu lar zone, and it colocalized with specific markers for neural precursor cel ls. In addition, data from flow-cytometry indicated that Prominin/CD133, a cell-surface marker for ventricular zone cells, was expressed specifically in these GFP-positive (GFP(+)) cells. After sorting by fluorescence-activat ed cell sorting, the GFP(+) cells proliferated in vitro and expressed precu rsor cell markers but not neuronal markers. Using clonogenic sphere formati on assays, we showed that this sorted population was enriched in multipoten t precursor cells that could differentiate into both neurons and glia. Impo rtantly, many neurons generated from nestin-GFP-sorted mesencephalic precur sors developed a dopaminergic phenotype in vitro. Finally, nestin-GFP(+) ce lls were transplanted into the striatum of a rat model of Parkinson's disea se. Bromodeoxyuridine-tyrosine hydroxylase double-labeling revealed that th e transplanted cells generated new dopaminergic neurons within the host str iatum. The implanted cells were able to restore dopaminergic function in th e host striatum, as assessed by a behavioral measure: recovery from ampheta mine-induced rotation. Together, these findings indicate that precursor cel ls harvested from the embryonic ventral mesencephalon can generate dopamine rgic neurons able to restore function to the chemically denervated adult st riatum.