2. Academic Validation
  3. Bidirectional fibrogenic cross-talk revealed in a human iPSC-derived epithelial-mesenchymal co-culture model of pulmonary fibrosis

Bidirectional fibrogenic cross-talk revealed in a human iPSC-derived epithelial-mesenchymal co-culture model of pulmonary fibrosis

  • bioRxiv. 2026 Jan 31:2026.01.30.702837. doi: 10.64898/2026.01.30.702837.
Andrea B Alber 1 2,  George Kwong 1 2,  Vishal K Gupta 1 2,  Porter E Dooley 1 2,  Jill R Patel 1 2,  Pushpinder S Bawa 1,  Kasey Minakin 1 2,  Dakota Jones 1 2,  Diya Gopal 1 2,  Huan Souza 3,  Maria Yampolskaya 3,  Eitan Vilker 1 2,  Chandani Sen 4,  Ansley S Conchola 5,  Pankaj Mehta 3,  Brigitte N Gomperts 4,  Tristan Frum 5,  Jason R Spence 5,  Konstantinos-Dionysios Alysandratos 1 2,  Darrell N Kotton 1 2
Affiliations

Affiliations

  • 1 Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA 02118, USA.
  • 2 The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA.
  • 3 Department of Physics, Boston University, Boston, MA 02215, USA.
  • 4 Department of Pediatrics, David Geffen School of Medicine, UCLA Children's Discovery and Innovation Institute, Mattel Children's Hospital, University of California, Los Angeles, CA 90095, USA.
  • 5 Department of Internal Medicine, Division of Gastroenterology and Hepatology, University of Michigan Medical School, Ann Arbor, MI 48109, USA.
PMID: 41659605 DOI: 10.64898/2026.01.30.702837
Abstract

Pulmonary fibrosis (PF) can arise from mutations in alveolar epithelial type 2 (AT2) cell-specific genes, but manifests in fibrotic activation of mesenchymal cells, thus involving fibrogenic epithelial-mesenchymal crosstalk. The ligand-receptor interactions underlying the onset and early progression of PF remain poorly understood. Induced pluripotent stem cell (iPSC)-derived models are powerful tools to study respiratory diseases, yet are currently limited to reductionist single lineage epithelial models or multi-lineage systems that lack purity and lung-specificity of the mesenchyme. Here we generate a human iPSC line carrying both a lung mesenchyme-specific reporter (TBX4-LERtdTomato) and a reporter for mesenchymal activation/differentiation (ACTA2GFP). Applying this line, we develop a directed differentiation protocol capable of generating cells that express key molecular and functional features of primary human developing lung mesenchyme across multiple iPSC genetic backgrounds. We then establish co-cultures of these iPSC-derived lung mesenchymal cells (iLM) with patient-specific iPSC-derived alveolar epithelial type 2 cells (iAT2s) carrying an SFTPCI73T mutation as a model for PF. We find increased expression of fibrotic markers in co-cultures with mutant iAT2s as compared to co-cultures with gene-corrected iAT2s. Moreover, mutant iAT2s express markers of alveolar-basal intermediate (ABI) cells only in the presence of iLM, suggesting that bidirectional crosstalk promotes this aberrant cell state. We identify ligand-receptor pairs enriched in co-cultures with mutant iAT2s, including TGFβ, multiple integrins, and additional genes that have not been previously linked to PF. Finally, we show that small molecule-mediated inhibition of TGFβ or integrins αvβ1/αvβ6 attenuates both fibrotic mesenchymal activation and the presence of ABI cells in iLM/iAT2 co-cultures. Thus, we have established a human iPSC-derived co-culture system that recapitulates key molecular hallmarks of bidirectional fibrogenic epithelial-mesenchymal crosstalk in pulmonary fibrosis, and enables the identification and study of potentially druggable pathways involved in disease initiation and progression.

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