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bioRxiv · 10.1101/2024.09.26.615125

Immortalization of human valve interstitial cells: an in vitro tool for studying fibro-calcific aortic valve degeneration

Moschetta, D.·Massaiu, I.·Bertolini, F.·Valerio, V.·Rusconi, V.·De Giorgi, D.·Myasoedova, V. A.·Poggio, P.
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Abstract

Human primary valve interstitial cells (VIC) are essential for studying the detrimental fibrocalcification processes typical of aortic valve degeneration. However, their limited lifespan poses a significant challenge. To address this, we immortalized VICs to extend their lifespan and facilitate genetic manipulation, enabling the study of dysregulated molecular and cellular pathways in this pathology and the test of potential drugs in vitro. We achieved immortalization by transducing primary VICs with simian virus 40 gene and human telomerase large T gene. Post-immortalization, we conducted RNA sequencing on both primary and immortalized VICs to identify pathways regulation following infection. Additionally, we assessed whether immortalized VICs retained their mesenchymal markers and responded to the pro-osteogenic and pro-calcific stimuli similarly to primary VICs. Given the comparable data obtained from both cell types, we propose using immortalized VICs as a reliable tool for in vitro study of fibro-calcific aortic valve degeneration.

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Moschetta, D., Massaiu, I., Bertolini, F., Valerio, V., Rusconi, V., De Giorgi, D., Myasoedova, V. A., Poggio, P.. 2024-09-26. Immortalization of human valve interstitial cells: an in vitro tool for studying fibro-calcific aortic valve degeneration. https://doi.org/10.1101/2024.09.26.615125

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