Line h1 embryonic stem cells

HIOs were generated and maintained as previously described^{2 (link)–4} . Briefly, line H1 embryonic stem cells (WiCell Research Institute, Inc.) were grown in feeder-free conditions in Matrigel (BD Biosciences) coated six-well Nunclon surface plates (Nunc) and maintained in mTESR1 media (Stem Cell Technologies). For induction of definitive endoderm (DE), cells were passaged with Accutase (Stem Cell Technologies) and plated at a density of 65,000 cells per well in 24-well Nunc plates. Cells were allowed to grow in mTESR1 media for two days before treatment with 100 ng/ml of Activin A for three days as previously described. DE was then treated with hindgut induction medium (RPMI 1640, 100x NEAA, 2% dFCS,) for four days with 100 ng/ml FGF4 (R&D) and 3 µM Chiron 99021 (Tocris) to induce formation of mid-hindgut spheroids. Spheroids were then plated in Growth Factor Reduced (GFR) Matrigel and maintained in intestinal growth medium (Advanced DMEM/F-12, N2 supplement, B27 supplement, 15 mM HEPES, 2 mM L-glutamine, penicillin-streptomycin) supplemented with 100 ng/ml EGF (R&D) to generate human intestinal organoids (HIOs). Media was changed twice weekly thereafter. HIOs were replated in fresh Matrigel every 14 days. HIOs were utilized for surgical transplantation between days 28 and 36.