Differentiation of human iPSCs into functional podocytes

PLoS One. 2018 Sep 17;13(9):e0203869. doi: 10.1371/journal.pone.0203869. eCollection 2018.

Abstract

Podocytes play a critical role in glomerular barrier function, both in health and disease. However, in vivo terminally differentiated podocytes are difficult to be maintained in in vitro culture. Induced pluripotent stem cells (iPSCs) offer the unique possibility for directed differentiation into mature podocytes. The current differentiation protocol to generate iPSC-derived podocyte-like cells provides a robust and reproducible method to obtain podocyte-like cells after 10 days that can be employed in in vitro research and biomedical engineering. Previous published protocols were improved by testing varying differentiation media, growth factors, seeding densities, and time course conditions. Modifications were made to optimize and simplify the one-step differentiation procedure. In contrast to earlier protocols, adherent cells for differentiation were used, the use of fetal bovine serum (FBS) was reduced to a minimum, and thus ß-mercaptoethanol could be omitted. The plating densities of iPSC stocks as well as the seeding densities for differentiation cultures turned out to be a crucial parameter for differentiation results. Conditionally immortalized human podocytes served as reference controls. iPSC-derived podocyte-like cells showed a typical podocyte-specific morphology and distinct expression of podocyte markers synaptopodin, podocin, nephrin and WT-1 after 10 days of differentiation as assessed by immunofluorescence staining or Western blot analysis. qPCR results showed a downregulation of pluripotency markers Oct4 and Sox-2 and a 9-fold upregulation of the podocyte marker synaptopodin during the time course of differentiation. Cultured podocytes exhibited endocytotic uptake of albumin. In toxicological assays, matured podocytes clearly responded to doxorubicin (Adriamycin™) with morphological alterations and a reduction in cell viability after 48 h of incubation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Culture Techniques / methods*
  • Cell Differentiation / physiology
  • Cell Survival
  • Cells, Cultured
  • Humans
  • Induced Pluripotent Stem Cells / metabolism*
  • Intracellular Signaling Peptides and Proteins
  • Membrane Proteins
  • Podocytes / metabolism*
  • Synaptophysin
  • WT1 Proteins

Substances

  • Intracellular Signaling Peptides and Proteins
  • Membrane Proteins
  • NPHS2 protein
  • SYNPR protein, human
  • Synaptophysin
  • WT1 Proteins
  • WT1 protein, human
  • nephrin

Grants and funding

The research leading to these results has received support from the Innovative Medicines Initiative Joint Undertaking under grant agreement no 115439 (StemBANCC, to GG, MB and PJ), resources of which are composed of financial contribution from the European Union Seventh Framework Programme (FP7/2007-2013) and EFPIA companies’ in-kind contribution. This publication reflects only the author’s views and neither the IMI JU nor EFPIA nor the European Commission are liable for any use that may be made of the information contained therein. Furthermore, the financial support by Foundation ProCare, Zürich, Switzerland, and Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach, Germany (to GG) and from the in3 Marie Skłodowska-Curie Action - Innovative Training Network under grant no. 721975 (to PJ) is also gratefully acknowledged. Boehringer Ingelheim Pharma GmbH & Co. KG supported in the form of salaries for authors [FM, MB] and consumables. FM and MB further supported in the study design and with analysis tools, but did not have a role in the decision to publish, or the preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section.