hiPSC NPCs were maintained at high density, grown on Matrigel in NPC media (DMEM/F12, 1× N2, 1× B27-RA (Invitrogen), and 20 ng/ml FGF2 (Invitrogen) and split approximately 1:3–1:4 every week with Accutase (Millipore)37. NPCs can be expanded beyond 10 passages. NPC experiments were conducted on passage-matched populations, between passages 9 and 12. Control hiPSC and NPC validation as shown39,75. All hiPSC and NPCs in the laboratory are tested monthly using MycoAlert (Lonza) to ensure they remain mycoplasma free.
