Project description:Fibroblasts are the main dermis-resident cells, yet they remain poorly characterized. Fundamentally, fibroblasts originate from the same population of mesenchymal cells but fibroblast subpopulations have been identified. Papillary and reticular fibroblasts were characterized based on their respective location in the papillary and reticular dermis. Here, we identified a new subset of fibroblasts, located in human papillary dermis and displaying specific features such as their organization into cell clusters. We used microarrays to detail the gene expression profiles of the novel fibroblast subpopulation we have identified compared to papillary and reticualr fibroblasts and notably the relative contribution of the different fibroblast subpopulations to the extracellular matrix of the dermis.
Project description:Fibroblasts synthesize the extracellular matrix of connective tissue and play an essential role in maintaining tissue integrity. We have previously shown that mouse skin connective tissue, the dermis, is comprised of functionally distinct fibroblast lineages. However, the extent of fibroblast heterogeneity in human skin is unknown. Here, using a combination of spatial transcriptional profiling of human and mouse dermis and single cell transcriptional profiling of human dermal fibroblasts, we show that there are at least four distinct fibroblast populations in adult human skin. We define markers permitting prospective isolation of these cells and show that although marker expression is rapidly lost in culture, different fibroblast subpopulations retain distinct functionality in terms of Wnt signalling, T cell communication and the ability to support human epidermal reconstitution in organotypic culture. Furthermore, while some fibroblast subpopulations are spatially segregated, others are not. These findings have profound implications for normal wound healing and diseases characterized by excessive fibrosis, and suggest that ex vivo expansion or in vivo ablation of specific fibroblast subpopulations may have therapeutic applications.
Project description:Nanostring nCounter Human Fibrosis V2.0 Panel Hidradenitis Suppurativa is a chronic inflammatory disease of which the pathogenesis is incompletely understood. Dermal fibroblasts have been previously identified as a major source of inflammatory cytokines, however information pertaining to the characteristics of subpopulations of fibroblasts in HS remains unexplored. Using in silico-deconvolution of whole-tissue RNAseq, Nanostring gene expression panels and confirmatory immunohistochemistry we identified fibroblast subpopulations in HS tissue and their relationship to disease severity and lesion morphology. Gene signatures of SFRP2+ fibroblast subsets were increased in lesional tissue, with gene signatures of SFRP1+ fibroblast subsets decreased. SFRP2+ and CXCL12+ fibroblast numbers, measured by IHC, were increased in HS tissue, with greater numbers associated with epithelialized tunnels and Hurley Stage 3 disease. Pro-inflammatory CXCL12+ fibroblasts were also increased, with reductions in SFRP1+ fibroblasts compared to healthy controls. Evidence of Epithelial Mesenchymal Transition was seen via altered gene expression of SNAI2 and altered protein expression of ZEB1, TWIST1, Snail/Slug, E-Cadherin and N-Cadherin in HS lesional tissue. The greatest dysregulation of EMT associated proteins was seen in biopsies containing epithelialized tunnels. The use of the oral Spleen tyrosine Kinase inhibitor Fostamatinib significantly reduced expression of genes associated with chronic inflammation, fibroblast proliferation and migration suggesting a potential role for targeting fibroblast activity in HS.
Project description:Human cells produce thousands of lipids that impact biological processes in ways we are only starting to characterize. The cellular composition in lipids changes during differentiation and also varies across individual cells of the same type. Yet, whether and how cell-to-cell differences in lipid composition affect cell phenotypes remain unknown. Here we have measured the lipidomes and transcriptomes of individual human dermal fibroblasts by coupling high-resolution mass spectrometry imaging to single-cell transcriptomics. We find that the cell-to-cell variation of specific lipid metabolic pathways contributes to the establishment of cell states involved in the organization of skin architecture. In fact, sphingolipid composition defines fibroblast subpopulations and its metabolic rewiring drives cell state transitions. These data uncover a role for cell-to-cell lipid heterogeneity in the determination of cell states and reveal a new regulatory component to the self-organization of multicellular systems.
Project description:Different types of hair follicles can be found in the skin of mice. It is believed that the signals that control hair follicle differentiation arise from cells in a structure called the dermal papilla. Understanding the nature of those signals is of interest for the biology of the normal tissue. We have developed a technique for isolation of dermal cells by enzymatic digestion of intact skin. We have identified two subpopulations of cells that can be separated by FACS. The Sox2-positive CD133-positive cells are found exclusively in the dermal papillae of guard/awl/auchene hairs, while Sox2-negative, CD133-positive cells are found in the other hair follicle types. We compared these populations with unfractionated dermal cells. We isolated the following 3 populations of cells from the back skin of neonatal mice (P2) by Flow Cytometry: 1) GFP-CD133- Total dermal cells 2) GFP-CD133+ Dermal Papilla cells 3) GFP+CD133+ Dermal Papilla cells The yield is approximately 50,000 cells of each population.
Project description:miR-29 can target many gene transcripts encoding extracellular matrix proteins. To unravel novel targets, we used microarray analysis to detect global gene expression changes when inhibiting endogenous miR-29. Total RNA from human dermal fibroblast cells after 48 h treatment with miR-29a inhibitor or control inhibitor were isolated and subjected to whole gene expression microarray analysis.
Project description:In previous study we found that Lnc-URIDS increased in diabetic dermal fibroblast and delayed wound healing.To further verify the roles of lnc-URIDS in fibroblast during wound heaing, A lnc-URIDS shRNA lentivirus and a control lentivirus were transfected into rat dermal fibroblast respectively (three independent replicates for each group) for 48h. Then, differential expressed genes between Control fibroblast and Lnc-URIDS knockdown fibroblast were detected by using microarray expression profiling though Agilent rat 4 x 44K gene expression microarrays (Agilent Technologies, Santa Clara, CA) .