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. Corneal injury can trigger inflammation and an aggressive wound healing response that can compromise immune privilege and avascularity, leading to vision loss. The effects of chronic inflammation on limbal stem cell (LSC) function and its ability to renew the epithelium, however, remain unclear. Here, we use a corneal suture model in C57Bl/6 male mice to induce epithelial damage, inflammation and neovascularization, to examine the impact on LSCs. Using single-cell transcriptomics, we evaluate corneal cell state changes and the potential of duloxetine, an FDA-approved medicine, to promote corneal homeostasis. We show with single-cell RNA-seq analysis a loss of homeostatic LSCs, basal, and differentiated epithelial cells, and an increase in transformed LSC, conjunctival, inflammatory, and vascular cell states following cornea injury, suggesting a coordinated wound healing response in different tissue layers. We show duloxetine promotes epithelial homeostasis, LSC identity maintenance, epithelial and stromal repair, and suppression of immune and vascular responses. The current treatment regimen is, however, insufficient to improve the corneal phenotype in the short term. Single-cell level dynamics reveal detailed drug modes of action, highlighting key aspects of LSC and corneal cell plasticity during tissue repair.