NPCs were re-plated on PLO/laminin-coated dishes or a 24-well plate at a density of 2 × 104 cells/cm2 in the neuronal differentiation medium comprising the neurobasal medium, 1% N2, 2% B27, 1% GlutaMax-1, 1% NEAA, 50 μM β-ME, 1% P/S, 20 ng/ml brain-derived neurotrophic factor (BDNF), 20 ng/ml glial-derived neurotrophic factor (GDNF), 20 ng/ml ciliary neurotrophic factor (CNTF). All growth factors and cytokines were purchased from R&D (Minneapolis, MN, USA), media and supplements were from Invitrogen (Carlsbad, NY, USA).
