Basic Fibroblast Growth Factor Supports the Function of Limbal Niche Cells via the Wnt/β-Catenin Pathway.

To test the effects and underlying mechanisms of basic fibroblast growth factor (bFGF) on the limbal niche cell (LNC) function . By using different concentrations of bFGF (0, 4, 8, 12, and 16 ng/mL) and fibroblast growth factor receptor (FGFR) inhibitors, the effects of bFGF on LNC proliferation, expression of stem cell markers, and transcription levels of the β-catenin were investigated. Single-cell RNA sequencing (scRNA-seq) was used to analyze the action and mechanisms of FGFR subtypes and the Wnt/β-catenin pathway during LNC culture. An mature corneal epithelial cell (MCEC)/LNC three-dimensional model was constructed to verify whether bFGF activates the Wnt/β-catenin pathway in LNC by inhibiting FGFR or β-catenin targets. scRNA-seq showed that is the main receptor in LNC, along with the molecules in the Wnt pathway, including and β-catenin. The 12 ng/mL bFGF treatment group showed higher LNC proliferation rate and transcription levels of , and β-catenin than any other groups ( < 0.001). In the MCEC/LNC co-culture model, MCEC/LNC treated with 12 ng/mL bFGF promoted the aggregation of the spheres than other groups, associated with increased transcription levels of , , β-catenin, and a decreased transcription level of ( < 0.001). Wnt/β-catenin inhibitor LF3 treatment reversed the abovementioned effect of bFGF. bFGF could maintain and promote the stemness of LNC via the /// axis in a concentration-dependent manner.