Abstract
The cornea, which refracts light toward the retina and acts as a protective barrier for the eye, is critical for our visual system. The corneal epithelium, continuously renewed by corneal epithelial stem cells (CESCs), is required to maintain corneal transparency and thus is critical for vision. Recent experiments in corneal epithelial lineage tracing, live imaging, and single-cell RNA sequencing have deepened our understanding of CESCs and uncovered their unexpected properties. In this review, we focus on recent progress in elucidating these essential properties of CESCs, including their location and how they maintain their populations and their heterogeneity. Additionally, we discuss the limitations of current studies and highlight critical issues that urgently need to be addressed in the field of CESCs. These new insights into CESCs will evolve into game-changing therapeutics for corneal diseases by harnessing CESCs in regenerative medicine.