Human embryonic stem cell H1 and H9 were obtained from UCLA Broad Stem Cell Research Center through license agreement with WiCell Research Institute. Cells were initially grown and propagated in hESC growth medium- Dulbecco's Modified Eagle's Medium/Ham's nutrient mixture F12 (DMEM/F12) supplemented with 20% Knockout Serum Replacement (KSR), 1 mM glutamate, 1% non-essential amino acids, 0.1 mM β-mercaptoethanol and 5 ng/ml basic fibroblast growth factor (bFGF) with mitotically inactivated mouse embryonic fibroblast (MEF) feeder layer. Before treatment, cells were transferred to mTeSR1 medium on matrigel-coated 100 mm plates without feeder cells using standard conditions (Stem Cell Technologies, Vancouver, BC, Canada) (Xu et al., 2001).
