Palfi S, Leventhal L, Chu Y, Ma SY, Emborg M, Bakay R, Déglon N, Hantraye P, Aebischer P, Kordower JH. Lentivirally delivered glial cell line-derived neurotrophic factor increases the number of striatal dopaminergic neurons in primate models of nigrostriatal degeneration. J Neurosci. 2002 Jun 15; 22(12):4942-54.