Project description:Genome wide DNA methylation profiling of epidermal and dermal samples obtained from sun-exposed and sun-protected body sites from younger (<35 years old) and older (>60 years old) individuals. The Illumina Infinium 450k Human DNA methylation Beadchip was used to obtain DNA methylation profiles across approximately 450,000 CpGs in dermal and epidermal samples. Samples included 10 younger sun protected dermal samples, 10 younger sun exposed dermal samples, 10 older sun protected dermal samples, 10 older sun exposed dermal samples, 9 younger sun protected epidermal samples, 9 younger sun exposed epidermal samples, 10 older sun protected epidermal sample, 10 older sun exposed epidermal samples.
Project description:Genome wide DNA methylation profiling of epidermal and dermal samples obtained from sun-exposed and sun-protected body sites from younger (<35 years old) and older (>60 years old) individuals. The Illumina Infinium 450k Human DNA methylation Beadchip was used to obtain DNA methylation profiles across approximately 450,000 CpGs in dermal and epidermal samples. Samples included 10 younger sun protected dermal samples, 10 younger sun exposed dermal samples, 10 older sun protected dermal samples, 10 older sun exposed dermal samples, 9 younger sun protected epidermal samples, 9 younger sun exposed epidermal samples, 10 older sun protected epidermal sample, 10 older sun exposed epidermal samples. Bisulphite converted DNA from the 78 samples were hybridized to the Illumina Infinium 450k Human Methylation Beadchip.
Project description:Gene expression profiling of epidermal samples obtained from sun-exposed and sun-protected body sites from younger (<35 years old) and older (>60 years old) individuals. The Affymetrix U133A plus 2.0 array was used to obtain gene expression data. Samples included 4 younger sun exposed epidermal samples, 4 older sun exposed epidermal samples, 3 younger sun protected epidermal samples, 5 older sun protected epidermal samples.
Project description:Here we used a pan-cytokeratin antibody to differentiate the epidermal from dermal compartment and assayed over 18,000 RNA probes from multiple regions of interest (ROI) comparing sun protected skin, and two regions (edge and center) from AK/sun damaged skin. This allows for a trajectory from sun protected to sun damaged within an individual. Traditionally, cancer biology focusses on change within the tumor compartment for diagnosis and staging and current genetic profiling of actinic keratosis (the precursor lesion for cutaneous squamous cell carcinoma) has focused on analysis limited to whole skin or the epidermal compartment alone. Here we use spatial transcriptomics to compare and contrast the epidermal and stromal compartments from different regions of actinic keratosis and matched sun protected skin from six individuals. Our data show that the major changes in AK at the transcriptional level are evident in the dermal compartment. Sun protected skin (n=5-6 from 6 individuals for a total of 34 ROI), the center of an AK lesion (n=3 for a total of 18 ROI) and edge of the AK lesion (n=2-3 for a total of 17 ROI) representing sun-damaged skin, from six unrelated individuals, the center of an AK lesion (n=3 for a total of 18 ROI) and edge of the AK lesion (n=2-3 for a total of 17 ROI) representing sun-damaged skin, from six unrelated individuals.
Project description:Here we used a pan-cytokeratin antibody to differentiate the epidermal from dermal compartment and assayed over 18,000 RNA probes from multiple regions of interest (ROI) comparing sun protected skin, and two regions (edge and center) from AK/sun damaged skin. This allows for a trajectory from sun protected to sun damaged within an individual. Traditionally, cancer biology focusses on change within the tumor compartment for diagnosis and staging and current genetic profiling of actinic keratosis (the precursor lesion for cutaneous squamous cell carcinoma) has focused on analysis limited to whole skin or the epidermal compartment alone. Here we use spatial transcriptomics to compare and contrast the epidermal and stromal compartments from different regions of actinic keratosis and matched sun protected skin from six individuals. Our data show that the major changes in AK at the transcriptional level are evident in the dermal compartment. Sun protected skin (n=5-6 from 6 individuals for a total of 34 ROI), the center of an AK lesion (n=3 for a total of 18 ROI) and edge of the AK lesion (n=2-3 for a total of 17 ROI) representing sun-damaged skin, from six unrelated individuals, the center of an AK lesion (n=3 for a total of 18 ROI) and edge of the AK lesion (n=2-3 for a total of 17 ROI) representing sun-damaged skin, from six unrelated individuals.
Project description:Human skin undergoes profound structural remodelling following chronic exposure to ultraviolet radiation (UVR) – photoageing - that is normally studied by comparing photoexposed and photoprotected skin sites. Whilst it is well established that the abundance and distribution of major dermal extracellular matrix (ECM) proteins (principally collagen I and elastin) are compromised in skin, the influence of UVR exposure on other skin protein constituents, including epidermal proteins, is poorly understood. We used label-free LC-MS/MS proteomics to characterise the proteomic profiles of intrinsically aged buttock and photoaged forearm epidermis and dermis. Besides traditional shotgun proteomics we have also developed and used novel proteomics analysis approach to reveal locational changes in peptide yields from proteins named Manchester Peptide Locational Fingerprinting (MPLF) which is based on spectral counting. MPLF is a new proteomic analysis tool that can identify structural modification-associated differences within proteins from label-free liquid chromatography tandem mass spectrometry (LC-MS/MS) datasets generated from biological samples. We have identified a total of 174 dermal proteins and 146 epidermal proteins with MPLF while relative quantification revealed a total of 635 dermal proteins and 926 epidermal proteins significantly different between photoaged forearm and intrinsically-aged buttock according to peak area intensity.
Project description:Fibroblasts are the main dermal cell type and are essential for the architecture and function of human skin. Important differences have been described between fibroblasts localized in distinct dermal layers, and these cells are also known to perform varied functions. However, this phenomenon has not been analyzed comprehensively yet. Here we have used single-cell RNA sequencing to analyze >15,000 cells from a sun-protected area in young and old donors. Our results define four main fibroblast subpopulations that can be spatially localized and functionally distinguished. Importantly, intrinsic aging reduces this fibroblast ‘priming’, generates distinct expression patterns of skin aging-associated genes, and substantially reduces the interactions of dermal fibroblasts with other skin cell types. Our work thus provides comprehensive evidence for a functional specialization of human dermal fibroblasts and suggests that the age-related loss of fibroblast priming contributes to human skin aging.