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Abstract Intracellular pH dynamics is increasingly recognized to regulate myriad cell behaviors. We report a finding that intracellular pH dynamics also regulates adult stem cell lineage specification. We identify an intracellular pH gradient in mouse small intestinal crypts, lowest in crypt stem cells and increasing along the crypt column. Disrupting this gradient by inhibiting H+efflux by Na+/H+exchanger 1 abolishes crypt budding and blocks differentiation of Paneth cells, which are rescued with exogenous WNT. Using single-cell RNA sequencing and lineage tracing we demonstrate that intracellular pH dynamics acts downstream of ATOH1, with increased pH promoting differentiation toward the secretory lineage. Our findings indicate that an increase in pH is required for the lineage specification that contributes to crypt maintenance, establishing a role for intracellular pH dynamics in cell fate decisions within an adult stem cell lineage.
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This content will become publicly available on April 22, 2026
Engineered epithelial curvature controls Paneth cell localization in intestinal organoids
The cellular organization within organoid models is important to regulate tissue-specific function, yet few engineering approaches can control or direct cellular organization. Here, a photodegradable hydrogel is used to create softened regions that direct crypt formation within intestinal organoids, where the dimensions of the photosoftened regions generate predictable and defined crypt architectures. Guided by in vivo metrics of crypt morphology, this photopatterning method is used to control the width and length of in vitro organoid crypts, which ultimately defines the curvature of the epithelium. By tracking expression of differentiated Paneth-cell markers in real time, we show that epithelial curvature directs the localization of Paneth cells within engineered crypts, providing user-directed control over organoid functionality. We anticipate that our improved control over organoid architecture and thus Paneth-cell localization will lead to more consistent in vitro organoid models for both mechanistic studies and translational applications.
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- Award ID(s):
- 2033723
- PAR ID:
- 10579153
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Cell Biomaterials
- ISSN:
- 25100046
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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