Donor Age Impairs Vasculogenic Potential of hiPSC-Derived Endothelial Progenitors

Background: Human induced pluripotent stem cells (hiPSCs) hold promise for vascular regeneration, but preliminary research often relies on neonatal donors, whereas clinical applications will use cells derived from aged individuals. Although the impact of donor age on reprogramming efficiency has been studied, its effect on the functionality of hiPSC-derived endothelial progenitors (hiPSC-EPs) remains unclear. This question is the focus of the current study. Methods and Results: We derived EPs from iPSCs sourced from three neonatal donors (ND) and three mature donors (MD) matched 1:1 for sex and somatic cell origin. We assessed their functional, epigenetic, and transcriptomic characteristics. Despite higher CD34? yields from MD-iPSCs, MD-hiPSC-EPs formed poorly interconnected and non-lumenized vascular structures in 3D hydrogels, compared to neonatal donor (ND) lines. In 2D culture, MD-hiPSC-EPs exhibited reduced cell density and aberrant VE-Cadherin localization. DNA methylation analysis revealed that somatic cell origin was the dominant driver of variance, but consistent differences in methylation of mesoderm commitment, angiogenesis, ECM remodeling, and cytoskeleton-related genes were observed between age groups. Epigenetic age prediction showed MD-hiPSC-EPs had more developmentally advanced signatures, potentially explaining their shift away from vasculogenic competence. Our RNA-sequencing findings confirm trends seen in the DNA methylation data and show differential expression of pathways linked to mitochondrial regulation and nitric oxide signaling. Conclusions: Donor age significantly alters the vasculogenic function of hiPSC-EPs. These findings underscore the necessity of donor-specific considerations in hiPSC-based vascular engineering and highlight potential barriers to translating hiPSC-derived therapeutics into aged patient populations.