Single-cell RNA transcriptome shows IFITM1 regulates stem cell activation in limbal epithelium in response to alkali burn.

To examine whether the upregulation of Ifitm1 is essential for the expansion of stem/early TA cells in response to corneal injury, wild type mouse eyes were topically treated with AAV-shRNA-Ifitm1 or AAV-empty vector (control) and subsequently were subjected to corneal NaOH burn. AAV-shRNA-Ifitm1 treatment downregulated Ifitm1 expression in mouse limbal epithelium . A scRNA-seq assay was conducted using cells isolated from corneal/limbal tissues at three days after corneas were injured. scRNA-seq assay identified stem/early TA cell population using Gpha2, a limbal epithelial stem /eTA cell marker. In AAV-EV treated mouse eyes, NaOH injury increased the numbers of the stem/eTA cells compared to uninjured eyes. Such expansion of stem/eTA cell population following corneal injury was markedly reduced in AAV-shRNA-Ifitm1 treated eyes. This suggests a positive role of Ifitm1 in stem/early TA cell expansion after corneal injury. Overall design: Methods: We conducted scRNA-seq on ocular anterior segmental tissue from 2 uninjured wild-type, 2 NaOH injured AAV-empty vector-transduced, and 2 NaOH injured AAV-shRNA-Ifitm1 transduced mice, using a 10X Gemomics pipeline. Cell populations were distinguished by UMAP embedding. Seurat analysis was conducted to compare gene expression profiles between these groups of mice.