Generation of Valvular Interstitial Cells from Human Pluripotent Stem Cells

Mazine, A.; Mikryukov, A. A.; Fernandes, I.; Liu, C. Z.; Jahangiri, S.; Martin, M.; Gähwiler, E. K.; Generali, M.; Gomez, J.; Latifi, N.; Miao, Y.; Liu, Y.; Laflamme, M.; Simmons, C. A.; Hoerstrup, S. P.; Emmert, M. Y.; Gelb, B. D.; Gu, M.; Keller, G.

doi:10.1101/2025.09.17.676963

bioRxiv · 10.1101/2025.09.17.676963

Generation of Valvular Interstitial Cells from Human Pluripotent Stem Cells

Mazine, A.·Mikryukov, A. A.·Fernandes, I.·Liu, C. Z.·Jahangiri, S.·Martin, M.·Gähwiler, E. K.·Generali, M.·Gomez, J.·Latifi, N.·Miao, Y.·Liu, Y.·Laflamme, M.·Simmons, C. A.·Hoerstrup, S. P.·Emmert, M. Y.·Gelb, B. D.·Gu, M.·Keller, G.

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Abstract

Heart valves are living structures whose sophisticated functions are mediated by a specialized population of mesenchymal cells known as valvular interstitial cells (VICs). Given their central role in valve homeostasis, VICs represent a promising cell population for studying heart valve diseases and developing novel therapies to treat them. Here, we describe a strategy for generating VICs from human pluripotent stem cells (hPSCs) by stage-specific manipulation of developmental signalling pathways. Our results demonstrate that hPSC-derived VICs show a high transcriptional similarity to primary human fetal VICs and can secrete key proteins of the valve extracellular matrix. We further investigate the heterogeneity of hPSC-derived VICs and identify two major subpopulations with distinct molecular and functional properties, mirroring the cellular diversity observed in vivo. Finally, we utilize an in vitro model of Noonan syndrome to demonstrate that hPSC-derived VICs can accurately recapitulate key aspects of valve disease. Collectively, these findings provide a reproducible method for the scaled generation of bona fide hPSC-derived VICs and establish their utility in disease modelling and tissue engineering applications. Clinical PerspectiveO_ST_ABSWhat is new?C_ST_ABS- We established a robust platform to generate bona fide valvular interstitial cells (VICs) from human pluripotent stem cells (hPSCs), recapitulating native VIC identity and function. - We delineated signaling pathways that promote the development of two distinct VIC subsets and identified a surface marker to distinguish between them. What are the clinical implications?- A renewable, human-specific source of VICs enables precise mechanistic studies of valve development and disease that are not possible with limited surgical specimens or animal models. - This platform creates opportunities for therapeutic applications, including drug discovery and tissue engineering approaches for valve repair.

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Mazine, A., Mikryukov, A. A., Fernandes, I., Liu, C. Z., Jahangiri, S., Martin, M., Gähwiler, E. K., Generali, M., Gomez, J., Latifi, N., Miao, Y., Liu, Y., Laflamme, M., Simmons, C. A., Hoerstrup, S. P., Emmert, M. Y., Gelb, B. D., Gu, M., Keller, G.. 2025-09-21. Generation of Valvular Interstitial Cells from Human Pluripotent Stem Cells. https://doi.org/10.1101/2025.09.17.676963

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