Objective: Although oral mucosal epithelial stem cells are thought to reside in the basal layer, such cells have not yet been isolated. We isolated a population of rabbit oral epithelial progenitor cells containing putative stem cells.
Materials and methods: Epithelial cells harvested from rabbit buccal mucosa were allowed to adhere to dishes coated with collagen IV for periods ranging from 10 min to 16 h. The properties of individual cell populations were evaluated using BrdU, Ki-67, integrin β1, integrin α6 and keratin 13 using colony forming efficiency (CFE).
Results: Cells that adhered to collagen IV-coated dishes within 10 min were enriched about sixfold in terms of BrdU incorporation, Ki-67, integrin α6 and integrin β1 were strongly expressed. Interestingly, keratin 13 was faintly expressed. The CFE of rapidly adherent cells among oral epithelial cells was significant compared with other cell populations.
Conclusions: These results suggested that rabbit oral epithelial cells could be isolated by depending on adhesiveness to collagen IV, especially when segregated according to progenitor cell properties. Putative progenitor cells with stem cell properties were most effectively harvested within 10 min. Our separation procedure should be a useful tool with which to isolate epithelial stem cells for regenerative medicine.