Project description:Human hair follicles from normal areas of the scalp were disassociated to single cells, sorted and tested by microarrray To compare the expression of human CD200+ CD49+ hair follicle keratinocytes versus CD200-CD49+ keratinocytes
Project description:Mouse back skin was disassociated to single cells, sorted by cell surface markers and tested by microarrray To compare the gene expression of mouse bulge (CD34+CD200+CD49+) versus secondary hair germ (CD34-CD200+CD49+) versus interfollicular epidermis (CD34-CD200-CD49+) xx Bald scalp retains hair follicle stem cells but lacks CD200-rich and CD34-positive hair follicle progenitor cells Androgenetic alopecia (AGA) or common baldness results from a marked decrease in hair follicle size. This miniaturization may be related to loss of hair follicle stem or progenitor cells. To test this hypothesis, we analyzed bald and non-bald scalp from the same individuals for the presence of hair follicle stem and progenitor cells using flow cytometry to quantitate cells expressing CYTOKERATIN 15 (KRT15), CD200, CD34 and ALPHA-6-INTEGRIN (ITGA6). High levels of KRT15 expression correlated with stem cell properties of small cell size and quiescence. Cells with the highest level of KRT15 expression were maintained in bald scalp; however, distinct populations of CD200high ITGA6high cells and CD34-positive cells were markedly diminished. Consistent with a progenitor cell phenotype, the diminished populations localized closely to the stem-cell rich bulge area but were larger and more proliferative than the bulge stem cells. In functional assays, analogous CD200 high /Itga6 high cells from murine hair follicles were multipotent and generated new hair follicles in skin reconstitution assays. These findings suggest that a defect in stem cell activation plays a role in the pathogenesis of AGA. 4 independent biologic replicates (each pooled from 3 distinct mice) were sorted for Mouse bulge (CD34+CD200+CD49+) versus secondary hair germ (CD34-CD200+CD49+) versus interfollicular epidermis (CD34-CD200-CD49+)
Project description:Mouse back skin was disassociated to single cells, sorted by cell surface markers and tested by microarrray To compare the gene expression of mouse bulge (CD34+CD200+CD49+) versus secondary hair germ (CD34-CD200+CD49+) versus interfollicular epidermis (CD34-CD200-CD49+) xx Bald scalp retains hair follicle stem cells but lacks CD200-rich and CD34-positive hair follicle progenitor cells Androgenetic alopecia (AGA) or common baldness results from a marked decrease in hair follicle size. This miniaturization may be related to loss of hair follicle stem or progenitor cells. To test this hypothesis, we analyzed bald and non-bald scalp from the same individuals for the presence of hair follicle stem and progenitor cells using flow cytometry to quantitate cells expressing CYTOKERATIN 15 (KRT15), CD200, CD34 and ALPHA-6-INTEGRIN (ITGA6). High levels of KRT15 expression correlated with stem cell properties of small cell size and quiescence. Cells with the highest level of KRT15 expression were maintained in bald scalp; however, distinct populations of CD200high ITGA6high cells and CD34-positive cells were markedly diminished. Consistent with a progenitor cell phenotype, the diminished populations localized closely to the stem-cell rich bulge area but were larger and more proliferative than the bulge stem cells. In functional assays, analogous CD200 high /Itga6 high cells from murine hair follicles were multipotent and generated new hair follicles in skin reconstitution assays. These findings suggest that a defect in stem cell activation plays a role in the pathogenesis of AGA.
Project description:The human hair follicle bulge is an important niche for keratinocyte stem cells (KSCs). Elucidation of human bulge cell biology could be facilitated by analysis of global gene expression profiles and identification of unique cell-surface markers. The lack of distinctive bulge morphology in human hair follicles has hampered studies of bulge cells and KSCs. In this study, we determined the distribution of label-retaining cells to define the human anagen bulge. Using navigated laser capture microdissection, bulge cells and outer root sheath cells from other follicle regions were obtained and analyzed with cDNA microarrays. Gene transcripts encoding inhibitors of WNT and activin/bone morphogenic protein signaling were overrepresented in the bulge, while genes responsible for cell proliferation were underrepresented, consistent with the existence of quiescent noncycling KSCs in anagen follicles. Positive markers for bulge cells included CD200, PHLDA1, follistatin, and frizzled homolog 1, while CD24, CD34, CD71, and CD146 were preferentially expressed by non-bulge keratinocytes. Importantly, CD200+ cells (CD200hiCD24loCD34loCD71loCD146lo) obtained from hair follicle suspensions demonstrated high colony-forming efficiency in clonogenic assays, indicating successful enrichment of living human bulge stem cells. The stem cell behavior of enriched bulge cells and their utility for gene therapy and hair regeneration will need to be assessed in in vivo assays.
Project description:The human hair follicle bulge is an important niche for keratinocyte stem cells (KSC). Elucidation of human bulge cell biology could be facilitated by analysis of global gene expression profiles and identification of unique cell surface markers. The lack of distinctive bulge morphology in human hair follicles has hampered studies of bulge cells and KSC. In this study, we determined the distribution of label-retaining cells to carefully define the human anagen bulge. Using navigated-laser capture microdissection, bulge cells and outer root sheath cells from other follicle regions were obtained and analyzed with cDNA microarrays. Gene transcripts encoding inhibitors of WNT and Activin/BMP signaling were over-represented in the bulge while genes responsible for cell proliferation were under-represented, consistent with quiescent non-cycling KSC in anagen follicles. Positive markers for bulge cells included CD200, PHLDA1, follistatin, and frizzled homolog 1 while CD24, 34, 71 and 146 were preferentially expressed by non-bulge keratinocytes. Importantly, CD200+ cells (CD200hi24lo34lo71lo146lo) obtained from hair follicle suspensions demonstrated high colony forming efficiency in clonogenic assays, indicating successful enrichment of living human bulge stem cells. Keywords: Affymetrix micrarray analysis of human hair follicles
Project description:We established a culture method of human keratinocytes from the bulge region of a plucked hair follicle, that contains multipotent epithelial stem cells with high proliferative potential. Using our method, keratinocyte cultures were successfully obtained from all subjects without invasive skin biopsies. We compared the gene expression profiles between the cultured keratinocytes derived from human hair-follicle-bulge (bulge–derived keratinocytes; BDKs) and neonatal human epidermal keratinocytes (NHEKs), and between BDKs from donors with atopic dermatitis and non-atopic controls using microarray analysis. Keywords: expressin profiling
Project description:We established a culture method of human keratinocytes from the bulge region of a plucked hair follicle, that contains multipotent epithelial stem cells with high proliferative potential. Using our method, keratinocyte cultures were successfully obtained from all subjects without invasive skin biopsies. We compared the gene expression profiles between the cultured keratinocytes derived from human hair-follicle-bulge (bulgeM-bM-^@M-^Sderived keratinocytes; BDKs) and neonatal human epidermal keratinocytes (NHEKs), and between BDKs from donors with atopic dermatitis and non-atopic controls using microarray analysis. Keywords: expressin profiling Two cell cultures, BDK vs. NHEK cells. 18 BDKs; derived from eighteen healthy volunteers , 6 NHEKs; purchased from Kurabo (Osaka, Japan). One replicate per array.
Project description:Androgenetic alopecia (AGA) or common baldness results from a marked decrease in hair follicle size. This miniaturization may be related to loss of hair follicle stem or progenitor cells. To test this hypothesis, we analyzed bald and non-bald scalp from the same individuals for the presence of hair follicle stem and progenitor cells using flow cytometry to quantitate cells expressing CYTOKERATIN 15 (KRT15), CD200, CD34 and ALPHA-6-INTEGRIN (ITGA6). High levels of KRT15 expression correlated with stem cell properties of small cell size and quiescence. Cells with the highest level of KRT15 expression were maintained in bald scalp; however, distinct populations of CD200high ITGA6high cells and CD34-positive cells were markedly diminished. Consistent with a progenitor cell phenotype, the diminished populations localized closely to the stem-cell rich bulge area but were larger and more proliferative than the bulge stem cells. In functional assays, analogous CD200 high /Itga6 high cells from murine hair follicles were multipotent and generated new hair follicles in skin reconstitution assays. These findings suggest that a defect in stem cell activation plays a role in the pathogenesis of AGA. This SuperSeries is composed of the SubSeries listed below.
Project description:A permantly active form of the oncogene Akt was expressed in the keratinocytes of the basal proliferative layer of the epidermis. Stem cells of the hair follicle expressing the cell surface marker CD34 were isolated. RNA form the CD34(+) and CD34(-) keratinocytes was extracted and and hybridized to Mouse Genome 430 2.0 Affymetrix arrays. Gene expression was compared between CD34(+) hair follicle stem cells and CD34(-) cells isolates from the back skin of K5-myrAkt transgenic mice.