ASN's Mission

To create a world without kidney diseases, the ASN Alliance for Kidney Health elevates care by educating and informing, driving breakthroughs and innovation, and advocating for policies that create transformative changes in kidney medicine throughout the world.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005

email@asn-online.org

202-640-4660

The Latest on X

Kidney Week

Abstract: SA-PO555

Optimized Culture Media Extends Human Kidney Organoid Longevity to 6 Months

Session Information

  • Bioengineering
    October 26, 2024 | Location: Exhibit Hall, Convention Center
    Abstract Time: 10:00 AM - 12:00 PM

Category: Bioengineering

  • 400 Bioengineering

Authors

  • Blackburn, Sophie M., University of Washington - Division of Nephrology, Department of Medicine, Kidney Research Institute, and Institute for Stem Cell and Regenerative Medicine, Seattle, Washington, United States
  • Sen, Arjun, University of Washington - Division of Nephrology, Department of Medicine, Kidney Research Institute, and Institute for Stem Cell and Regenerative Medicine, Seattle, Washington, United States
  • Freedman, Benjamin S., University of Washington - Division of Nephrology, Department of Medicine, Kidney Research Institute, and Institute for Stem Cell and Regenerative Medicine, Seattle, Washington, United States
Background

Although kidney organoids, derived from human pluripotent stem cells (hPSC), mature in vitro in approximately 3 weeks, there is an interest in using this model to study the effects of microgravity on the kidney during long-term space flight. The most widely used kidney organoid protocols consider their structures mature between day 16 and day 28 of differentiation, generally completing experimental assays at that time or shortly thereafter.

Methods

Standard kidney organoid differentiation was performed until cultures reached the renal vesicle stage. We then supplemented our standard differentiation media with organoid tubular enhancing media (OTEM) which contains components proposed to promote epithelial cell growth and limit de-differentiation. Organoid counts were obtained using full-well brightfield images and nephron segments were visualized using immunostaining. Viability was assessed with a colorimetric assay. Transcriptomic analysis was performed via single-cell RNA sequencing of kidney organoid cultures at days 25 and 180 of differentiation.

Results

OTEM drastically improved the longevity of kidney organoids, whereas no kidney organoids survived past day 100 when treated with standard media. After six months of culture, structural and transcriptomic analyses showed viable podocytes, proximal tubules, and distal tubules present in OTEM treated kidney organoids. We also identified an early glomerular epithelial cell cluster that grew relative to other cell types over the course of the experiment.

At day 26 of differentiation, cultures treated with OTEM had four-fold more kidney organoids than those grown in standard media. Furthermore, the OTEM-treated cultures had less stromal overgrowth and contained twice as many viable cells compared to controls.

Conclusion

Our findings indicate that OTEM is improving the stability of kidney organoids and supporting the proliferation of cell types that indicate increasing maturity of the structures. This is a simple yet powerful change to our differentiation protocol that sets the stage for future studies of organoid aging on earth and in space.

Timecourse of OTEM-treated kidney organoids

Funding

  • Other U.S. Government Support