Abstract: TH-PO0534
Investigating the Early Origins of the Metanephric Mesenchyme
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
- Ferran-Heredia, Carlos, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States
- McCracken, Kyle, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States
Group or Team Name
- McCracken Lab.
Background
The mammalian kidney derives from the metanephric mesenchyme (MM) which arises from the posterior-most region of the intermediate mesoderm (IM) and contributes to the stromal and nephron progenitors of the kidney. Key features of the MM include its ability to self-renew, to self-organize, and to drive complex morphogenetic events through interactions with the ureteric bud. Although putative MM-like cells have been differentiated from human pluripotent stem cells (hPSCs) to generate nephron-containing kidney organoids, they do not exhibit these advanced properties. We hypothesize that these deficiencies result from the failure of in vitro protocols to faithfully recapitulate the early steps of MM formation in vivo, which are currently undefined. To address this critical knowledge gap, we sought to precisely delineate the differentiation pathway that generates MM in the embryo. First, by identifying the specific gastrulation-stage progenitors, and then by mapping the stepwise fate decisions required to form posterior IM.
Methods
We used in vivo genetic lineage tracing models, single cell transcriptomic analysis, and wholemount immunofluorescence staining to trace gastrulation-stage axial progenitors through embryonic development and to characterize MM formation.
Results
Temporally inducible lineage labelling demonstrated that the nephron and stromal progenitor pools of the MM derive from neuro-mesodermal competent axial progenitors in the caudal lateral epiblast. These axial progenitors committed to a mesodermal fate between E7.5-E8.5 to form the early tailbud mesoderm and subsequently the MM. This suggests a shared progenitor between posterior paraxial and IM. In contrast to the conventional view of early mesoderm formation in the gastrula, the labelled axial progenitors exhibited potential to form neural but not endodermal derivatives. Through single cell profiling and trajectory analyses, we identified the lineage fate decisions by which these progenitors differentiate into IM and MM.
Conclusion
In summary, this is the first comprehensive analyses of the origin of the MM. Our data provides a new roadmap to be used as a reference to differentiate hPSCs into more authentic MM progenitor cells and to address the self-renewing and self-organizing capacity of the MM that is currently lacking in kidney organoid models.
Funding
- Other NIH Support