Single cell transcriptomic analysis of nephron and UB lineages in recombinant hPSC-derived kidney organoids grown under various conditions.

To model tissue interactions in kidney development, a protocol was devised to combine human pluripotent stem cell (hPSC)-derived ureteric bud progenitors with nephrogenic mesenchyme to form kidney organoids. The resulting organoids had a complex composition including the nephron, ureteric, stromal, and endothelial lineages. scRNA-seq was performed to catalog and analyze the populations and developmental trajectories of the different lineages. Kidney organoids were generated by combining induced ureteric bud (UB) and nephrogenic mesenchyme (NM) progenitor cells. Organoids were sampled at days 0, 3, 7, 10, and 14 under standard baseline conditions. Control organoids comprising only NM or UB were also analyzed. Additional conditions were also including: organoids with NOTCH inhibition (DAPT) from days 4-6 and organoids grown in collecting duct (CD) medium +/- A83, U0126, and XAV939 from days 10-14.