Kidney Week

Abstract: SA-PO992

Modeling Podocytopathies in Human Kidney Organoids

Session Information

• Glomerular Diseases: Podocyte Biology - II
  November 04, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Glomerular Diseases

• 1403 Podocyte Biology

Authors

• El Saghir, Jamal, University of Michigan Michigan Medicine, Ann Arbor, Michigan, United States

Jamal El Saghir,

• Berthier, Celine C., University of Michigan Michigan Medicine, Ann Arbor, Michigan, United States

Celine C. Berthier,

• Lassé, Moritz, Universitatsklinikum Hamburg-Eppendorf, Hamburg, Hamburg, Germany

Moritz Lassé,

• Fischer, Matthew, University of Michigan Michigan Medicine, Ann Arbor, Michigan, United States

Matthew Fischer,

• Minakawa, Akihiro, University of Michigan Michigan Medicine, Ann Arbor, Michigan, United States

Akihiro Minakawa,

• Vega-Warner, V., University of Michigan Michigan Medicine, Ann Arbor, Michigan, United States

V. Vega-Warner,

• Menon, Rajasree, University of Michigan Michigan Medicine, Ann Arbor, Michigan, United States

Rajasree Menon,

• Rinschen, Markus M., Universitatsklinikum Hamburg-Eppendorf, Hamburg, Hamburg, Germany

Markus M. Rinschen,

• Kretzler, Matthias, University of Michigan Michigan Medicine, Ann Arbor, Michigan, United States

Matthias Kretzler,

• Harder, Jennifer L., University of Michigan Michigan Medicine, Ann Arbor, Michigan, United States

Jennifer L. Harder,

Group or Team Name

• MiKTMC.

Background

Podocytopathies include multiple kidney diseases such as Focal Segmental Glomerulosclerosis (FSGS) and Minimal Change Disease (MCD) in which podocyte injury results in albuminuria. Kidney organoids (KOrgs) derived from human pluripotent stem cells generate 3D architecture with multiple cell types seen in native kidneys more reflective of the human in vivo podocyte environment. The aim of this study was to assess KOrg podocyte (KOrg-podos) response to inflammatory stressors and hypoxia and to evaluate their ability to capture pathways relevant to human podocytopathies.

Methods

KOrgs were treated with recombinant TNFα or interferon-γ (IFNG) or subjected to 1% O₂ environment for 24 and 48h. Assessment of gene/protein expression in KOrgs included qRT-PCR, bulk and single cell (Sc) RNAseq, ELISA, IF and untargeted proteomics. Probability of ligand-target cell engagement was assessed by NicheNet based on differential protein expression. Organoid stressor-specific gene signatures were generated from bulk RNA-seq and/or proteomics data and used to assess summary gene expression in proteinuric human kidney tissue (NEPTUNE cohort).

Results

Proteomics analysis showed that baseline KOrgs expressed >90% proteins detected in human glomeruli; IF imaging confirmed anticipated localization of slit diaphragm proteins SYNPO and CD2AP in KOrg-podos. Further, NicheNet analysis confirmed that KOrg-podos responded to a host of ligands expressed by other cell types. Following treatment with TNFα, IFNG or hypoxia, Sc transcriptional profiling revealed that KOrg-podos lose expression of key podocyte markers (NPHS1, PODXL) and increase expression of genes observed in early glomerular epithelial cells (LYPD1, CDH6) as well as pathways associated with inflammatory response (NFkB) and mitochondrial stress. KOrgs stressor-specific gene signature expression segregated subgroups of individuals in a podocytopathic cohort.

Conclusion

Our multi-platform integrative analysis of KOrgs demonstrates that KOrg-podos functionally respond to multiple stimuli thought to contribute to podocytopathies. Further, KOrgs stressor-specific gene activity identified individuals with poor outcome in proteinuric kidney disease. These results confirm the relevance of KOrgs to studies of molecular mechanisms of podocytopathies.

Funding

• NIDDK Support – Eli Lilly