Control and SCZD HFs were obtained from cell repositories and were reprogrammed with tetracycline-inducible lentiviruses expressing the transcription factors OCT4, SOX2, KLF4, cMYC and LIN287. Lentiviruses were packaged in 293T HEK cells transfected with Polyethylenimine (PEI) (Polysciences). HFs were transduced and then split onto mouse embryonic fibroblasts (mEFs). Cells were switched to HUES media (KO-DMEM (Invitrogen), 10% KO-Serum Replacement (Invitrogen), 10% Plasminate (Talecris), 1x Glutamax (Invitrogen), 1x NEAA (Invitrogen), 1x 2 mercaptoethanol (Sigma) and 20 ng/ml FGF2 (Invitrogen)) and 1 µg/ml Doxycycline (Sigma) was added to HUES media for the first 21–28 days of reprogramming. hiPSCs were generally grown in HUES media: early passage hiPSCs were split through manual passaging, while at higher passages hiPSCs could be enzymatically passaged with 1mg/ml Collagenase (Sigma).
