Single-cell transcriptomic comparison of the developing human fetal stomach and pluripotent stem cell-derived gastric organoids.

The goal of engineering increasingly complex human organoid models is to more accurately model human organogenesis and disease. Recently, human antral gastric organoids (hAGOs) were engineered to contain splanchnic mesenchyme (SM) and enteric neural crest cells (NCCs), resulting in functional three germ layer gastric organoids. To determine the robustness of hAGOs and how additional germ layers impact development, we benchmarked these hAGOs with the developing human stomach. Human AGOs in vitro were most similar to 7 week fetal stomach with the epithelium comprising primarily mucous precursors. The SM and NCCs added to hAGOs formed fetal gastric-like mesenchymal or neuroglial precursors, respectively. Incorporation of SM and NCCs did not drastically alter the cellular diversity of the epithelium in vitro. Following transplantation, hAGOs with SM matured into tissue more like the 2nd trimester stomach. Bioinformatic inference confirmed known signaling crosstalk between germ layers and identified new signaling candidates that may regulate tissue assembly. Together, three germ layer hAGOs faithfully model the multilayer complexity of the fetal stomach at the single-cell transcriptomic level and provide insight into human stomach development.