• DOI:10.1038/s41556-020-00591-9
• Corpus ID: 222319682

Gli1+ mesenchymal stromal cells form a pathological niche to promote airway progenitor metaplasia in the fibrotic lung

@article{Cassandras2020Gli1MS,
  title={Gli1+ mesenchymal stromal cells form a pathological niche to promote airway progenitor metaplasia in the fibrotic lung},
  author={Monica Cassandras and Chaoqun Wang and Jaymin J. Kathiriya and Tatsuya Tsukui and Peri Matatia and Michael A. Matthay and Paul J. Wolters and Ari B. Molofsky and Dean Sheppard and Hal Chapman and Tien Peng},
  journal={Nature cell biology},
  year={2020},
  volume={22},
  pages={1295 - 1306}
}

• Monica Cassandras, Chaoqun Wang, +8 authors Tien Peng
• Published 18 September 2020
• Biology
• Nature cell biology

Aberrant epithelial reprogramming can induce metaplastic differentiation at sites of tissue injury, culminating in transformed barriers composed of scar and metaplastic epithelium. While the plasticity of epithelial stem cells is well-characterized, the identity and role of the niche has not been delineated in metaplasia. Here we show that Gli1+ mesenchymal stromal cells (MSCs), previously shown to contribute to myofibroblasts during scarring, promote metaplastic differentiation of airway progenitors into KRT5+ basal cells. During fibrotic repair, Gli1+ MSCs integrate hedgehog activation to upregulate BMP antagonism in the progenitor niche that promotes metaplasia. Restoring the balance towards BMP activation attenuated metaplastic KRT5+ differentiation while promoting adaptive alveolar differentiation into SFTPC+ epithelium. Finally, fibrotic human lungs demonstrate altered BMP activation in the metaplastic epithelium. These findings show that Gli1+ MSCs integrate hedgehog signaling as a rheostat to control BMP activation in the progenitor niche to determine regenerative outcome in fibrosis.