1.25–5 × 105 NPCs (per well) were seeded onto poly-L-ornithine/Laminin-coated 12- or 48-well MEA plate (Axion), respectively. Transduction, spinfection, doxycycline addition, puromycin selection and Ara-C treatment were performed as described above. NPC medium was replaced with neuron medium, and half media changes, every second day were completed thereafter. Doxycycline was withdrawn at various time points, as indicated (Fig. 6B). After 14 days of induction, the MEA plate was loaded in the Axion Maestro MEA reader, the electrical activity of mNgn2-induced neurons was recorded and analyzed by the AxIS 2.0 software.
