TH and Parkinson disease: In the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced monkey model of PD, intrastriatal injected endometrium-derived mesenchymal stromal cells (EDSCs) demonstrated neuron-like morphology, expressed tyrosine hydroxylase (TH), and eventually augmented the frequency of TH-expressing cells in vivo.