Abstract
Purpose: :
Purpose: To explore the potential of murine hair follicle (HF)-derived epithelial stem cells to replenish corneal epithelium using a murine limbal stem cell deficiency model.
Methods: :
Methods: We used a tet-On tri-transgenic Krt12rtTA/rtTA/tet-O-Cre/ROSAmTmG dual-reporter mouse line which allowed the detection of hair follicle progenitor (stem) cells that differentiate to express cytokeratin 12 (K12) and convert red to green fluorescence upon doxycycline induction. Epithelial stem cells (SC) were isolated from vibrissa HF of whole-body-red tri-transgenic mice. The SC were enriched by clonal expansion on a 3T3 feeder cell layer over 14 days and subsequently subcultured for 7 days on fibrin gels as a transplantable carrier. The presence of red or green fluorescence was checked microscopically prior to transplantation onto 17 limbal SC deficient WT mice and at various time points post-transplantation. Post-transplantation the mice were fed with doxycycline chow to allow detection of K12 expression in engrafted hair follicle-derived cells.
Results: :
Results: Post-transplantation 30% of the engrafted fibrin-based HF-epithelial constructs derived from the transgenic mice showed signs of transdifferentiation and an increasing expression (green fluorescence) of the corneal epithelial differentiation marker K12 over the following three weeks. An immunohistochemical staining using an antibody against K12 additionally confirmed K12 expression in the engrafted hair follicle-derived epithelial cells. The corneal integrity and opacity were found to be satisfactory after fluorescein staining and microscopic examination.
Conclusions: :
Conclusions: HF-derived epithelial SC possess the potential to be reprogrammed into corneal epithelial-like phenotype. They are able to express K12 and regenerate the corneal epithelium when transplanted in a murine limbal SC deficiency model.
Keywords: cornea: basic science • cornea: epithelium • transplantation