Hypoxic culture maintains cell growth of the primary human valve interstitial cells with stemness. Hypoxic culture maintains cell growth of the primary human valve interstitial cells with stemness

Characterization of aortic valve interstitial cells (VICs) maintained in an optimized culture is es-sential for understanding the molecular mechanism underlying aortic valve stenosis. Here, we propose 2% hypoxia as an optimum VIC culture condition. Harvested leaflets from patients with aortic valve regurgitation were digested using collagenase and VICs were cultured under the 2% hypoxic condition. Significant elevation in VIC growth was observed in the 2% hypoxia group (hypo-VICs), compared to the normoxia group (normo-VICs). RNA-sequencing revealed that downregulation of oxidative stress-marker genes (such as superoxide dismutase) and upregula-tion of cell cycle accelerators (such as cyclins) were detected in hypo-VICs. Overall design: To characterize VICs cultured in hypoxic condition (hypo-VICs), we examined the gene expression profiles of hypo-VICs using RNA-sequencing and evaluated their ability to differentiation into osteoblasts.