Spatiotemporal Transcriptomic Dissection Uncovers Age-Dependent Deceleration of Esophageal Cell Differentiation

Precise orchestration of stem and progenitor cells is essential for tissue homeostasis and regeneration but becomes dysregulated during aging. Despite the known markers, the age-related dynamics of esophageal epithelial cell lineages remain unclear. Using single-cell single cell transcriptomics, we analyzed human esophageal epithelia across different age groups. We identified two stem cell populations: quiescent (qeSCs) and proliferative (peSCs) esophageal stem cells. qeSCs from young donors showed higher WNT10A expression and Wnt signaling activity. Analysis of cell lineage trajectories combined with cell plastic potentials showed stronger connectivity between peSCs and differentiated cells in younger tissues, indicating more efficient and rapid epithelial turnover and homeostatic maintenance. Cell-cell interaction analysis further demonstrated that NOTCH signaling is more prominent within peSCs and qeSCs in younger esophagi, whereas in older tissues, NOTCH activity is preferentially retained in differentiated cells. Additionally, the inflammatory signaling, Interleukin-1 pathway, is more active in younger esophagi but is largely restricted to differentiated cells. Our findings suggest that age-related decline in esophageal homeostasis is primarily driven by impaired differentiation dynamics rather than by alterations in stem cell self-renewal capacity.