Reassessing K15 as an Epidermal Stem Cell Marker
March 2011
in “
Stem Cell Reviews and Reports
”
Research cited in this study
16 / 16 resultsresearch Nonviral in Situ Green Fluorescent Protein Labeling and Culture of Primary, Adult Human Hair Follicle Epithelial Progenitor Cells
research Epidermal Homeostasis: A Balancing Act of Stem Cells in the Skin
Skin stem cells are crucial for maintaining and repairing the skin and hair, using a complex mix of signals to do so.
research Markers to Evaluate the Quality and Self-Renewing Potential of Engineered Human Skin Substitutes In Vitro and After Transplantation
Cytokeratin 19 and cytokeratin 15 are key markers for monitoring the quality and self-renewing potential of engineered skin.
research Multi-Potentiality of a New Immortalized Epithelial Stem Cell Line Derived from Human Hair Follicles
Scientists created a long-lasting stem cell line from human hair that can turn into different skin and hair cell types.
research The human keratins: biology and pathology
Keratins are crucial for cell stability, wound healing, and cancer diagnosis.
research Vibrissa Hair Bulge Houses Two Populations of Skin Epithelial Stem Cells Distinct by Their Keratin Profile
There are two types of stem cells in rodent hair follicles, each with different keratin proteins.
research Claudin Expression Modulations Reflect an Injury Response in the Murine Epidermis
Claudin expression changes help the skin respond to injury.
research Scratching the Surface of Skin Development
The document concludes that skin stem cells are important for hair growth and wound healing, and could be used in regenerative medicine.
research Delayed Epidermal Permeability Barrier Formation and Hair Follicle Aberrations in Inv-Cldn6 Mice
Mice with too much Claudin-6 have skin barrier problems and abnormal hair growth.
research Location and phenotype of human adult keratinocyte stem cells of the skin
The study identified markers for distinguishing stem cell, transit amplifying, and differentiating compartments in adult human skin using flow cytometry. Epidermal cells with high α6 integrin and low CD71 (α6briCD71dim) were identified as stem cells, comprising 2%-5% of the K14bri fraction, characterized by quiescence, small size, and high clonogenic capacity. In contrast, cells with high levels of both α6 integrin and CD71 (α6briCD71bri) were identified as transit amplifying cells, actively cycling with intermediate clonogenic capacity. Differentiating cells were marked by low α6 integrin (α6dim) and poor clonogenic efficiency. The study concluded that stem and transient amplifying cells were located in the deep rete ridges, while differentiating cells were in the shallow rete ridges.
research Keratin 15 Promoter Targets Putative Epithelial Stem Cells in the Hair Follicle Bulge
The study investigated the keratin 15 (K15) promoter's role in targeting epithelial stem cells in the hair follicle bulge using K15/lacZ transgenic mice. It was found that K15 expression was age-dependent and correlated with keratinocyte differentiation levels, with strong expression in less differentiated cells in the neonatal epidermis and adult bulge area. The K15 promoter specifically targeted bulge cells, which are thought to be stem cells, throughout all hair cycle stages, with 92%±3% of K15/lacZ-positive cells being label-retaining, indicating a quiescent stem cell phenotype. This research provided a valuable tool for further studies on hair follicle biology, wound healing, and carcinogenesis.
research Keratin 15 Expression in Stratified Epithelia: Downregulation in Activated Keratinocytes
research Expression of the Intermediate Filament Keratin Gene,K15,in the Basal Cell Layers of Epithelia and the Hair Follicle
research Onset of Keratin 17 Expression Coincides with the Definition of Major Epithelial Lineages during Skin Development
Keratin 17 is important for skin development and may help define skin cell types.
research The Epidermis: Rising to the Surface
The document concludes that recent research has improved understanding of skin diseases and the balance between cell growth and differentiation in the epidermis.
research Expression of keratin K14 in the epidermis and hair follicle: insights into complex programs of differentiation.
The study examined the expression of keratin K14 in human skin, particularly in the epidermis and hair follicles, using monospecific antisera and cRNA probes. It was found that K14 expression and filament organization differed significantly between the hair follicle and epidermis. In the outer root sheath (ORS) cells, which are mitotically active, K14 expression was low, and keratin filaments were fewer and more loosely organized compared to basal epidermal cells. As ORS cells differentiated, they increased K14 expression and formed denser keratin bundles. In contrast, matrix cells, which can differentiate into the inner root sheath, cuticle, and hair shaft, did not express K14 or form keratin filaments. Instead, they produced hair-specific keratins and dense filament bundles without inducing K14 expression. The study suggested that the patterns of K14 expression and filament organization in skin epithelial cells were linked to their pluripotency and highlighted the distinct differentiation programs of hair follicles compared to other stratified squamous epithelia.
Related Research
5 / 5 resultsresearch Keratins of the Human Hair Follicle
The document reviewed the genomic organization and expression characteristics of human hair keratin genes, highlighting their role in hair follicle biology and hereditary disorders. It noted that research on human hair keratins lagged behind studies in other species. The review discussed the complex regulatory mechanisms of hair keratin expression and the differentiation of hair follicle compartments. It also addressed keratin-related pathologies, such as epidermolysis bullosa simplex and pachyonychia congenita, which affect the outer root sheath and nail beds, respectively. The study emphasized the need for further research to understand the molecular mechanisms governing hair follicle differentiation and keratin expression.
research Expression of E6 and E7 papillomavirus oncogenes in the outer root sheath of hair follicles extends the growth phase and bypasses resting at telogen.
research Effects of Epidermal Growth Factor on the Morphology and Patterns of DNA Synthesis in Isolated Human Hair Follicles
EGF makes hair follicles grow longer but stops hair production.
research Expression of keratin K14 in the epidermis and hair follicle: insights into complex programs of differentiation.
The study examined the expression of keratin K14 in human skin, particularly in the epidermis and hair follicles, using monospecific antisera and cRNA probes. It was found that K14 expression and filament organization differed significantly between the hair follicle and epidermis. In the outer root sheath (ORS) cells, which are mitotically active, K14 expression was low, and keratin filaments were fewer and more loosely organized compared to basal epidermal cells. As ORS cells differentiated, they increased K14 expression and formed denser keratin bundles. In contrast, matrix cells, which can differentiate into the inner root sheath, cuticle, and hair shaft, did not express K14 or form keratin filaments. Instead, they produced hair-specific keratins and dense filament bundles without inducing K14 expression. The study suggested that the patterns of K14 expression and filament organization in skin epithelial cells were linked to their pluripotency and highlighted the distinct differentiation programs of hair follicles compared to other stratified squamous epithelia.