Goblet Cell Differentiation Potential in Human Corneal Limbal Epithelial Progenitor Cells In Vitro

PURPOSE. The existence of goblet cells has been regarded as a critical differential point to distinguish conjunctival epithelium from corneal epithelium in vivo. We tested differentiation potential of single progenitor cells from corneal limbal epithelium with growth factors in vitro. METHODS. Dissociated single cells from corneal limbal epithelium were cultured in the serum- and feeder cell-free medium containing B27 and various growth factors using nontissue culture dishes. Specific marker expression was examined in the colonies stimulated with growth factors. Differentiation of some mucosal epithelia was tested. RESULTS. Adherent single cells from dissociated single cells in corneal limbal epithelium did not proliferate in the serum- and feeder cell-free medium containing B27 only and formed corneal epithelium with B27 plus epidermal growth factor, while they gave rise to goblet cell with periodic acid Schiff-positive mucin and cytokeratin-3 and -12 expressing corneal epithelium with fibroblast growth factor (FGF)2 stimulation. Colonies stimulated with FGF2 expressed goblet cell specific MUC5AC and cytokeratin-7 mRNA and protein. FGF receptor 1 was a functional receptor for the differentiation to goblet cells and corneal epithelium. CONCLUSIONS. Single corneal limbal progenitor cells give rise to goblet cells and corneal epithelium by FGF2 stimulation via FGF receptor 1 in vitro.