Identification of Epithelial Stem Cells In Vivo and In Vitro Using Keratin 19 and BrdU
Progress in the identification of skin stem cells and the improvement of culture methods open the possibility to use stem cells in regenerative medicine. Based on their quiescent nature, the development of label retention assays allowed the localization of skin stem cells in the bulge region of the pilosebaceous units and in the bottom of rete ridges in glabrous skin. The development of markers such as keratin 19 also permits their study in human tissues. In this chapter, protocols to identify skin stem cells based on their slow-cycling property and their expression of keratin 19 will be described in detail. The methods include the labeling of skin stem cells within mouse or rat tissues in vivo, the labeling of proliferative human cells in vitro using 5-bromo-2-deoxyuridine (BrdU), and the detection of keratin 19 and BrdU by immunofluorescence or immunoperoxidase staining.
Key wordsCell culture Epidermis Hair follicle Human Keratinocytes Keratin 19 Mouse Proliferation Rat Regenerative medicine Stem cells Vibrissa
The authors would like to thank current and former members of the LOEX laboratory who have contributed to develop the foregoing protocols, particularly Claudia Fugère and Israël Martel. We are thankful to Nathalie Tremblay for her help regarding the research of technical information.
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