B Schematic illustration that outlines induction of the naïve-like state from primed hPSCs. Primed hPSCs were first cultured as single cells in conventional hPSC medium in the presence of ROCK inhibitor (ROCKi) and Y27632 (day 0). The medium was replaced by serum-free medium plus 2a2iL on day 1 without ROCKi. Compact dome-shaped colonies began to appear on day 3. The resultant naïve-like cells were passaged as single cells in the absence of ROCKi on day 5 in 2iL medium. 2a2iL-hPSCs were passaged every 3 to 4 days in 2iL, and kept typical naïve-like morphology for over 50 passages. 