Abstract: TH-OR062

Human iPSC-Derived Glomeruli Facilitate Accurate Modeling of Podocytopathy

Session Information

Category: Glomerular

  • 1003 Glomerular: Cell Biology

Authors

  • Hale, Lorna J., Murdoch Childrens Research Institute, MELBOURNE, New South Wales, Australia
  • Howden, Sara E., Murdoch Childrens Research Institute, MELBOURNE, New South Wales, Australia
  • Phipson, Belinda, Murdoch Childrens Research Institute, MELBOURNE, New South Wales, Australia
  • Ghobrial, Irene, Murdoch Childrens Research Institute, MELBOURNE, New South Wales, Australia
  • Er, Pei Xuan, Murdoch Children's Research Institute, Parkville, New South Wales, Australia
  • Kumar, Santhosh V, Murdoch childrens research institute, Melbourne, New South Wales, Australia
  • Oshlack, Alicia, Murdoch Childrens Research Institute, MELBOURNE, New South Wales, Australia
  • Little, Melissa H., Murdoch Childrens Research Institute, MELBOURNE, New South Wales, Australia
Background

Numerous kidney diseases leading to proteinuria result from alterations to the podocyte which leads to foot process effacement and loss of slit diaphragms. Immortalised cell lines have been the gold standard in podocyte biology, however, this model has inherent limitations. Consequently, validation of novel disease-associated mutations is most often performed in animal models which may not replicate the human condition. The advent of iPSC organoids now provides a new avenue for the study of human podocyte disease ex utero.

Methods

Sieved glomeruli isolated from human iPSC kidney organoids were characterised and compared to conditionally immortalised human podocytes by RNA-sequencing. The capacity of organoid-derived glomeruli to recapitulated podocytopathy through introduction of clinically relevant mutations into iPSC was assessed using CRISPR-Cas9 technology.

Results

Organoid-derived glomeruli showed superior podocyte-specific gene expression when compared to conditionally immortalised podocytes, with an upregulation of 2187 genes. GO terms associated with slit diaphragm development, and glomerular epithelial cell differentiation and development were significantly enriched. Glomeruli isolated from homozygous MAFB mutant organoids accurately recapitulated anticipated disease related transcriptional changes.

Conclusion

We provide the first evidence that human iPSC kidney organoids can accurately model podocytopathy. Organoid podocytes which are allowed to form in 3D via the patterning and segmentation seen during normal nephrogenesis are superior to the current gold standard conditionally immortalised podocyte cell system. The capacity to readily generate such an accurate model of the human glomerulus from iPSC will facilitate patient-specific functional genomics to validate novel podocytopathy genes and further interrogate the pathogenic mechanisms of existing podocytopathies in vitro.

Funding

  • Government Support - Non-U.S.