Abstract: TH-PO0562
Regulation of Nephrogenesis Events Within Kidney Organoids
Session Information
- Development, Stem Cells, and Regenerative Medicine
November 06, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Development, Stem Cells, and Regenerative Medicine
- 600 Development, Stem Cells, and Regenerative Medicine
Authors
- Noto, Rio, RIKEN, Center for Biosystems Dynamics Research, Kobe, Hyogo Prefecture, Japan
- Takasato, Minoru, RIKEN, Center for Biosystems Dynamics Research, Kobe, Hyogo Prefecture, Japan
Background
In the developing kidney, nephron progenitor cells (NPCs) undergo mesenchymal-to-epithelial transition (MET), leading to the sequential formation of pretubular aggregates (PTAs), renal vesicles (RVs), and functional nephrons. Leveraging developmental biology, human iPSCs can be directed to form kidney organoids via WNT pathway activation, which induces MET and promotes 3D self-organization. Enhancing nephron induction efficiency is essential for advancing kidney organoid-based regenerative therapies; however, the regulatory mechanisms governing RV formation remain incompletely understood.
Methods
To elucidate the underlying mechanism, we employed a culture system to induce RV formation from hiPSCs. Time-course single-cell RNA sequencing was conducted to identify the cell populations driving MET.
Results
Kidney organoids prior to nephrogenesis contained not only nephron progenitor cells (NPCs), but also stromal, vascular, and off-target cells. NPC subclustering revealed shifts in subpopulation sizes after stimulation. Notably, specific subclusters showed marked cell depletion, suggesting differentiation. These clusters transiently expressed early MET markers at 8–12 hours, aligning with transition into pretubular aggregates (PTAs) and renal vesicles (RVs). A downstream Wnt target gene was upregulated after 12 hours, mainly in RVs.
Focusing on the NPC subclusters that declined in number following stimulation—presumed to represent undifferentiated, MET-competent populations—we conducted CellChat analysis, designating them as signal receivers. This revealed several candidate pathways, including midkine (MK) and non-canonical Wnt5. Based on these findings, we optimized the culture conditions to influence specific signaling environments and promote the generation of high-quality NPCs with improved MET responsiveness.
Intervening in specific signaling pathways uncovered by CellChat analysis resulted in improved MET efficiency, underscoring the critical role of their regulation in directing nephron differentiation.
Conclusion
These findings provide mechanistic insights into early nephron differentiation and underscore the importance of intercellular signaling in guiding MET within kidney organoids. By pinpointing key pathways that regulate NPC behavior, this work contributes to optimizing organoid-based kidney models, with potential applications in disease modeling, drug screening, and regenerative medicine.