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Updated: Oct 22, 2025
Author Spotlight: Optimizing iPSC Differentiation for Efficient Production to Generate Kidney Organoids
Published on: September 1, 2023
Angiotensin II biphasically regulates cell differentiation in human iPSC-derived kidney organoids
Stacy M Yanofsky1, Courtney M Dugas1, Akemi Katsurada1
1Department of Physiology and Hypertension and Renal Center of Excellence, Tulane University School of Medicine, New Orleans, Louisiana.
Abstract:
Human kidney organoid technology holds promise for novel kidney disease treatment strategies and utility in pharmacological and basic science. Given the crucial roles of the intrarenal renin-angiotensin system (RAS) and angiotensin II (ANG II) in the progression of kidney development and injury, we investigated the expression of RAS components and effects of ANG II on cell differentiation in human kidney organoids. Human induced pluripotent stem cell-derived kidney organoids were induced using a modified 18-day Takasato protocol. Gene expression analysis by digital PCR and immunostaining demonstrated the formation of renal compartments and expression of RAS components. The ANG II type 1 receptor (AT1R) was strongly expressed in the early phase of organoid development (around day 0), whereas ANG II type 2 receptor (AT2R) expression levels peaked on day 5. Thus, the organoids were treated with 100 nM ANG II in the early phase on days 0-5 (ANG II-E) or during the middle phase on days 5-10 (ANG II-M). ANG II-E was observed to decrease levels of marker genes for renal tubules and proximal tubules, and the downregulation of renal tubules was inhibited by an AT1R antagonist. In contrast, ANG II-M increased levels of markers for podocytes, the ureteric tip, and the nephrogenic mesenchyme, and an AT2R blocker attenuated the ANG II-M-induced augmentation of podocyte formation. These findings demonstrate RAS expression and ANG II exertion of biphasic effects on cell differentiation through distinct mediatory roles of AT1R and AT2R, providing a novel strategy to establish and further characterize the developmental potential of human induced pluripotent stem cell-derived kidney organoids.NEW & NOTEWORTHY This study demonstrates angiotensin II exertion of biphasic effects on cell differentiation through distinct mediatory roles of angiotensin II type 1 receptor and type 2 receptor in human induced pluripotent stem cell-derived kidney organoids, providing a novel strategy to establish and further characterize the developmental potential of the human kidney organoids.
Insights
Human kidney organoids reveal biphasic effects of angiotensin II on cell differentiation. Angiotensin II type 1 receptor and type 2 receptor mediate distinct developmental roles, offering new strategies for kidney organoid research.
Area of Science:
- Stem cell biology and regenerative medicine
- Renal physiology and pathophysiology
- Developmental biology
Background:
- Human kidney organoids are promising models for studying kidney development and disease.
- The intrarenal renin-angiotensin system (RAS) and angiotensin II (ANG II) are critical in kidney development and injury.
- Understanding ANG II's role in kidney organoid differentiation is crucial for their application.
Purpose of the Study:
- To investigate the expression of RAS components in human kidney organoids.
- To determine the effects of ANG II on cell differentiation during organoid development.
- To elucidate the distinct roles of ANG II type 1 receptor (AT1R) and type 2 receptor (AT2R) in mediating these effects.
Main Methods:
- Generation of human induced pluripotent stem cell-derived kidney organoids using a modified Takasato protocol.
- Gene expression analysis via digital PCR and immunostaining to confirm renal compartment formation and RAS component expression.
- Treatment of organoids with ANG II during early (days 0-5) and middle (days 5-10) developmental phases, with and without AT1R and AT2R antagonists.
Main Results:
- RAS components were expressed in developing kidney organoids.
- Early ANG II exposure (ANG II-E) with AT1R activation decreased renal tubule markers, while middle phase exposure (ANG II-M) with AT2R activation increased podocyte and ureteric tip markers.
- Specific receptor antagonists (AT1R and AT2R blockers) modulated the respective ANG II-induced differentiation effects.
Conclusions:
- Human kidney organoids express RAS components and respond to ANG II in a biphasic manner.
- AT1R mediates inhibitory effects on renal tubule differentiation in early development.
- AT2R promotes differentiation of podocytes and other cell types in later developmental stages, offering novel strategies for organoid development and characterization.
