Perturbation of epithelial and limbal stem cell identity in a mouse model of pathologic corneal neovascularization
The epithelial layer of the cornea is a critical physical and ocular immune barrier for maintaining tissue integrity, homeostasis, and transparency for proper vision. Corneal injury can trigger inflammation, impair wound healing and compromise immune privilege and avascularity, leading to vision loss. Moreover, injury to the cornea can disrupt the engine of epithelial repair and restoration, the limbal stem cell (LSC) niche. Here we used a corneal suture model to induce epithelial damage, sustained inflammation and neovascularization, to examine the impact on LSCs. Using single-cell transcriptomics, we analyzed corneal cell state changes and additionally evaluated the potential of duloxetine, an FDA-approved medicine, to promote wound healing and corneal homeostasis. Single-cell RNA-seq analysis revealed loss of homeostatic limbal stem cells, basal and differentiated epithelial cells and an increase in distinct limbal-like, conjunctival, inflammatory, and vascular cell states, suggesting a coordinated wound healing response in different tissue layers. Importantly, duloxetine treatment promoted epithelial homeostasis, enhanced stem cell-like and stromal repair processes, and suppressed immune and vascular responses. Examination of corneal cell perturbation and transformations at the single-cell level thorough marker profile annotations can improve the understanding of LSC plasticity and function while yielding potential biomarkers of corneal repair processes.