Vibrissa hair bulge houses two populations of skin epithelial stem cells distinct by their keratin profile

• DOI: 10.1096/fj.07-8109com
• Publication Date: 2007-12-28T01:14:21Z
• Authors: Danielle Larouche; Xuemei Tong; Julie Fradette; Pierre A. Coulombe; Lucie Germain
• Keywords: Keratin 5; Epidermis (zoology); Keratin 14

Defining the properties of postnatal stem cells is interest given their relevance for tissue homeostasis and therapeutic applications, such as skin engineering burn patients. In hair follicles, bulge region outer root sheath houses cells. We show that explants from prominent area, but not bulb, in rodent vibrissa follicles can produce epidermis a model engineering. Using morphological criteria keratin expression, we typified epithelial bulge. Two types slow-cycling (Bb, Bs1) featuring high colony-forming capacity occur Bb are located outermost basal layer, express K5, K15, K17, K19, feature loosely organized network. Bs1 localize to suprabasal layers proximal K5/K17, correlating with network densely bundled filaments. These bundles missing K17-null mice, which lack vibrissa. Atypically, both keratinocytes K14 expression. findings heterogeneity within follicle cell repository, establish subset location, point special role K5/K17 filaments newly defined Our results discussed context long-term survival engineered tissues after grafting requires presence