Project description:BMP signalling is a potent regulator of skin morphogenesis, homeostasis and remodelling. However, molecular mechanisms underlying its involvement in regulating gene expression programs in keratinocytes and fibroblasts remain largely unknown. We analyzed the effect of BMP4 tratment on gene expression programs in human primary epidermal keratinocyte and dermal fibroblasts cultures. We identified specific changes in gene expression programs for each cell type. The primary human epidermal keratinocytes and dermal fibroblasts were treated with recombinant BMP4 or solvent control for 8 hours to reveal early and intermediate response genes. The RNA was isolated and used for micro-array analysis. Changes in gene expression programs were analyzed for each cell type and were compared between cell types.
Project description:BMP signalling is a potent regulator of skin morphogenesis, homeostasis and remodelling. However, molecular mechanisms underlying its involvement in regulating gene expression programs in keratinocytes and fibroblasts remain largely unknown. We analyzed the effect of BMP4 tratment on gene expression programs in human primary epidermal keratinocyte and dermal fibroblasts cultures. We identified specific changes in gene expression programs for each cell type.
Project description:In search for factors, overexpression of which in human dermal fibroblasts causes direct conversion to cells similar to keratinocytes, micro RNA expression profiles of human primary keratinocytes and human primary dermal fibroblasts are investigated. Skin samples obtained from 3 different sites of 1 subject were used for establishment of 3 primary keratinocytes and 3 primary dermal fibroblasts. Thus obtained 3 primary keratinocytes and primary dermal fibroblasts underwent micro RNA profiling.
Project description:To induce the differentiation, undifferentiated human pluripotent stem cells (both hESC andh iPSC; T0 time point) were transferred into 20% O2 atmosphere environment and treated with mTESR1 basal media supplemented with 1 μM ATRA (Sigma-Aldrich) and 25 ng/ml BMP4 (R&D) for 7 days (Induction). To select for the cells that acquired early ectodermal fate, cells were harvested and re-plated onto freshly prepared 3D human dermal fibroblast ECM at a density of 5-10x10^3 cells per cm2 and grown in DMEM:Ham F12 (3:1) (Life Technologies) supplemented with 1 μM ATRA and 25 ng/ml BMP4 for a further 7 days (Selection). To enrich for putative epidermal progenitors, rapid-adhesion to type IV collagen-coated dishes was used, and the rapidly-adhering cells were cultured in DK SFM supplemented with 1 μM ATRA for 7 days (Enrichment). After that, the cells were cultured in EpiLife medium (Life Technologies) for a further 7 days (Expansion) before final harvest (T3 time point) and analysis. We analyzed here gene expression profiles of undifferentiated hESC/hiPSC (T0), hESC/hIPC-derived keratinocytes (T3) and primary normal human keratinocytes from skin biopsy (NHK). We found that hESC/hIPC-derived keratinocytes are similar to NHK. Biological triplicates of undifferentiated (T0) hESC (KCL034) and hiPSC lines (iKCL004, iKCL011) were compared with hESC/hiPSC-derived keratinocytes (T3), primary human keratinocyes (NHK) and fibroblasts (BJ).
Project description:We present for the first time the direct molecular effects of microneedling therapy on epidermal keratinocytes and dermal fibroblasts using a standardized 3D skin model. Microneedling treatment resulted in histological alterations and changed the expression of various genes related to epidermal differentiation, inflammation, and dermal remodeling. We speculate that skin microneedling plays a role in dermal remodeling, increases epidermal differentiation, and might also have a direct effect on collagen synthesis. These findings may increase our understanding of the molecular mechanisms of human skin repair induced by microneedling therapy and will allow comparisons with competing applications, such as laser therapies
Project description:Hair follicle formation depends on reciprocal epidermal-dermal interactions and occurs during skin development, but not in adult life. This suggests that the properties of dermal fibroblasts change during postnatal development. To examine this, we used a PdgfraEGFP mouse line to isolate GFP-positive fibroblasts from neonatal skin, adult telogen and anagen skin and adult skin in which ectopic hair follicles had been induced (EF skin) by transgenic epidermal activation of beta-catenin. We also isolated epidermal cells from each mouse. The gene expression profile of EF epidermis was most similar to that of anagen epidermis, consistent with activation of beta-catenin signalling. In contrast, adult dermis with ectopic hair follicles more closely resembled neonatal dermis than adult telogen or anagen dermis. In particular, genes associated with mitosis were upregulated and extracellular matrix-associated genes were downregulated in neonatal and EF fibroblasts. We confirmed that sustained epidermal beta-catenin activation stimulated fibroblasts to proliferate to reach the high cell density of neonatal skin. In addition, the extracellular matrix was comprehensively remodelled, with mature collagen being replaced by collagen subtypes normally present only in developing skin. The changes in proliferation and extracellular matrix composition originated from a specific subpopulation of fibroblasts located beneath the sebaceous gland. Our results show that adult dermis is an unexpectedly plastic tissue that can be reprogrammed to acquire the molecular, cellular and structural characteristics of neonatal dermis in response to cues from the overlying epidermis. We have isolated the following populations of cells from mouse back skin by flow cytometry: 1A) GFP+ WT neonatal dermal fibroblasts, 1B) ItgA6+ WT neonatal epidermal keratinocytes, 2A) GFP+ WT telogen dermal fibroblasts, 2B) ItgA6+ WT telogen epidermal keratinocytes, 3A) GFP+ D2 transient activation (anagen) dermal fibroblasts, 3B) ItgA6+ D2 transient activation (anagen) epidermal keratinocytes, 4A) GFP+ D2 sustained activation (ectopic follicles) dermal fibroblasts, 4B) ItgA6+ D2 sustained activation (ectopic follicles) epidermal keratinocytes
Project description:Head and neck squamous cancer stromal fibroblasts produce growth factors influencing phenotype of normal human keratinocytes. Epithelial-mesenchymal interaction between stromal fibroblasts and cancer cells influences the functional properties of tumor epithelium including the tumor progression and spreading. We compared fibroblasts prepared from stroma of squamous cell carcinoma and normal dermal fibroblasts concerning their biological activity towards normal keratinocytes assessed by immunocytochemistry and profiling of gene activation for growth factors/cytokines by microarray chip technology. IGF-2 and BMP-4 were determined as candidate factors responsible for tumor associated fibroblast activity that influence normal epithelia. This effect was confirmed by addition of recombinant IGF-2 and BMP4 respectively to the culture medium. This hypothesis was also verified by inhibition experiments where blocking antibodies were employed in medium conditioned by cancer associated fibroblast. Presence of these growth factors was also detected in tumor samples.
Project description:We have used RNA-sequencing on six different proliferating cell lines consisting of normal human dermal fibroblasts (NHDF), normal human epidermal keratinocytes (NHEK), pericytes (PC), human microvADSCular blood endothelial cells (HMEC), lymphatic endothelial cells (LEC) and adipose derived stem cells (ADSC), subjected to different doses of radiotherapy.
Project description:In skin homeostasis, dermal fibroblasts are responsible for coordinating the migration and differentiation of overlying epithelial keratinocytes. As hairy skin heals faster than non-hairy skin, we hypothesised that follicular fibroblasts would accelerate skin re-epithelialisation after injury faster than interfollicular fibroblasts. We found that hair follicle dermal papilla fibroblast conditioned media (DPFi CM) could significantly accelerate wound closure compared to controls partly due to the presence of sAXL in this media. We used microarrays to identify upregulated and downregulated genes in human epidermal keratinocytes incubated with sAXL, DPFi CM and Epilife (keratinocyte growth media;control) after scratch wounds in vitro.
Project description:We performed whole-genome methylation analysis using 450K Illumina BeadArrays on different human cell types. In total 24 experiments were performed. Dermal fibroblasts, three different epidermal melanocytes (dark, medium and light pigmentation), epidermal keratinocytes, mammary fibroblasts, mammary epithelial cells, mammary endothelial cells and mesenchymal stem cells were analyzed in technical duplicates. Unmethylated DNA were analyzed in technical duplicates. Two different normal breast tissue samples were analyzed. Finally peripheral blood leukocytes and an enzymatically methylated sample were analyzed. Genome-wide DNA methylation analysis of different cell types using Illumina Human Methylation 450K Beadchips.