SOX9-induced Generation of Functional Astrocytes Supporting Neuronal Maturation in an All-human System

Stem Cell Rev Rep. 2021 Oct;17(5):1855-1873. doi: 10.1007/s12015-021-10179-x. Epub 2021 May 12.


Astrocytes, the main supportive cell type of the brain, show functional impairments upon ageing and in a broad spectrum of neurological disorders. Limited access to human astroglia for pre-clinical studies has been a major bottleneck delaying our understanding of their role in brain health and disease. We demonstrate here that functionally mature human astrocytes can be generated by SOX9 overexpression for 6 days in pluripotent stem cell (PSC)-derived neural progenitor cells. Inducible (i)SOX9-astrocytes display functional properties comparable to primary human astrocytes comprising glutamate uptake, induced calcium responses and cytokine/growth factor secretion. Importantly, electrophysiological properties of iNGN2-neurons co-cultured with iSOX9-astrocytes are indistinguishable from gold-standard murine primary cultures. The high yield, fast timing and the possibility to cryopreserve iSOX9-astrocytes without losing functional properties makes them suitable for scaled-up production for high-throughput analyses. Our findings represent a step forward to an all-human iPSC-derived neural model for drug development in neuroscience and towards the reduction of animal use in biomedical research.

Keywords: All-human co-culture system; Astrocytes; Differentiation protocol; Genome engineering; Pluripotent stem cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Astrocytes* / cytology
  • Humans
  • Induced Pluripotent Stem Cells / cytology
  • Mice
  • Neural Stem Cells* / physiology
  • Neurogenesis / physiology
  • Neurons / cytology
  • SOX9 Transcription Factor / metabolism


  • SOX9 Transcription Factor
  • SOX9 protein, human