The directed differentiation of human iPS cells into kidney podocytes

PLoS One. 2012;7(9):e46453. doi: 10.1371/journal.pone.0046453. Epub 2012 Sep 28.

Abstract

The loss of glomerular podocytes is a key event in the progression of chronic kidney disease resulting in proteinuria and declining function. Podocytes are slow cycling cells that are considered terminally differentiated. Here we provide the first report of the directed differentiation of induced pluripotent stem (iPS) cells to generate kidney cells with podocyte features. The iPS-derived podocytes share a morphological phenotype analogous with cultured human podocytes. Following 10 days of directed differentiation, iPS podocytes had an up-regulated expression of mRNA and protein localization for podocyte markers including synaptopodin, nephrin and Wilm's tumour protein (WT1), combined with a down-regulation of the stem cell marker OCT3/4. In contrast to human podocytes that become quiescent in culture, iPS-derived cells maintain a proliferative capacity suggestive of a more immature phenotype. The transduction of iPS podocytes with fluorescent labeled-talin that were immunostained with podocin showed a cytoplasmic contractile response to angiotensin II (AII). A permeability assay provided functional evidence of albumin uptake in the cytoplasm of iPS podocytes comparable to human podocytes. Moreover, labeled iPS-derived podocytes were found to integrate into reaggregated metanephric kidney explants where they incorporated into developing glomeruli and co-expressed WT1. This study establishes the differentiation of iPS cells to kidney podocytes that will be useful for screening new treatments, understanding podocyte pathogenesis, and offering possibilities for regenerative medicine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Activins / pharmacology*
  • Animals
  • Bone Morphogenetic Protein 7 / pharmacology*
  • Cell Aggregation
  • Cell Differentiation / drug effects*
  • Cell Membrane Permeability
  • Cell Proliferation
  • Cells, Cultured
  • Coculture Techniques
  • Fluorescein-5-isothiocyanate / analogs & derivatives
  • Fluorescein-5-isothiocyanate / metabolism
  • Fluorescent Dyes / metabolism
  • Gene Expression
  • Humans
  • Induced Pluripotent Stem Cells / drug effects
  • Induced Pluripotent Stem Cells / metabolism
  • Induced Pluripotent Stem Cells / physiology*
  • Kidney / cytology
  • Mesangial Cells / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Octamer Transcription Factor-3 / genetics
  • Octamer Transcription Factor-3 / metabolism
  • Podocytes / metabolism*
  • Podocytes / physiology
  • Serum Albumin / metabolism
  • Tissue Culture Techniques
  • Tretinoin / pharmacology*

Substances

  • Bone Morphogenetic Protein 7
  • FITC-albumin
  • Fluorescent Dyes
  • Octamer Transcription Factor-3
  • POU5F1 protein, human
  • Serum Albumin
  • activin A
  • Activins
  • Tretinoin
  • Fluorescein-5-isothiocyanate

Grant support

This work was supported by the Alport Foundation of Australia and a Monash University Strategic Grant. CA Bernard is a recipient of an Erdi Fellowship in Neurological Diseases and funding from the Baker Foundation. Microscopy was performed with technical expertise from Monash Micro Imaging, Monash University. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.