Figure 3. Generating new organoid models with reporter cell lines.

Development and optimization of new organoid generation methods can be greatly accelerated by genomically engineered fluorescence reporter stem cells. In this example, a red fluorescent protein (RFP) gene is integrated at a gene that is expressed in precursor cells. The successfully derived precursor cell‐containing organoids will exhibit red fluorescence, allowing quick identification of optimal deriving conditions. Similarly, via multiplex genome editing in the same stem cell line, a green fluorescence protein (GFP) gene integrated at a gene that is expressed in the mature target cell type will assist protocol development for generating mature organoids. A short 2A “self‐cleaving” peptide sequence (shown in blue) can be placed between the target gene and the fluorescence protein for non‐destructive labeling.