Project description:Foetal skin is known to heal without scar. This ability is lost in the third trimester of gestation. In mouse, scarless wound healing was reported until the day 15-16 of gestation. A range of factors that could explain the mechanisms of scarless skin wound healing have been identified, to mention reduced immune response, a greater proportion of collagen type III, hyaluronic acid and transforming growth factor beta isoform 3. The involvement of epigenetic changes, which are known to determine developmental processes, has not been examined in the context of scarless foetal skin healing so far. We performed the microarray analysis methylome and transcriptome of murine foetal dorsal skin at embryonic day 15 contrasted with those in later phases at embryonic days 18-19 as well as the in the adult mouse. The group of genes which show decreased methylation status in the foetal skin before the loss of ability to scarless healing between embryonic day 15 and 18 are enriched with transcriptional factors involved in embryonic morphogenesis, epithelium development, neuron differentiation, and synapse functions. The genes with increased methylation after the transition are associated with cell death and epithelial cell differentiation, inflammatory and wounding response and the degradation of hyaluronic acid. A substantial part of DNA methylation differences observed between embryonic day 15 and 18 were retained later at embryonic day 19 and in adults and remarkably correlated with gene expression changes. A major part of genes encoding the key factors responsible for cutaneous wound healing show significant changes in gene expression following the transition from scar free to normal healing. The results show that skin methylome and transcriptome undergoe extensive alterations following the loss of ability to scarless healing, while the functions associated with the changes imply their central role in skin wound repair.
Project description:Foetal skin is known to heal without scar. This ability is lost in the third trimester of gestation. In mouse, scarless wound healing was reported until the day 15-16 of gestation. A range of factors that could explain the mechanisms of scarless skin wound healing have been identified, to mention reduced immune response, a greater proportion of collagen type III, hyaluronic acid and transforming growth factor beta isoform 3. The involvement of epigenetic changes, which are known to determine developmental processes, has not been examined in the context of scarless foetal skin healing so far. We performed the microarray analysis methylome and transcriptome of murine foetal dorsal skin at embryonic day 15 contrasted with those in later phases at embryonic days 18-19 as well as the in the adult mouse. The group of genes which show decreased methylation status in the foetal skin before the loss of ability to scarless healing between embryonic day 15 and 18 are enriched with transcriptional factors involved in embryonic morphogenesis, epithelium development, neuron differentiation, and synapse functions. The genes with increased methylation after the transition are associated with cell death and epithelial cell differentiation, inflammatory and wounding response and the degradation of hyaluronic acid. A substantial part of DNA methylation differences observed between embryonic day 15 and 18 were retained later at embryonic day 19 and in adults and remarkably correlated with gene expression changes. A major part of genes encoding the key factors responsible for cutaneous wound healing show significant changes in gene expression following the transition from scar free to normal healing. The results show that skin methylome and transcriptome undergoe extensive alterations following the loss of ability to scarless healing, while the functions associated with the changes imply their central role in skin wound repair.
Project description:Wound healing is a well-organized dynamic process involving coordinated consecutive phases: homeostasis, inflammation, proliferation and resolution. Fibroblasts play major roles in skin wound healing such as in wound contraction and release of growth factors which are of importance in angiogenesis and tissue remodeling. Abnormal fibroblast phenotypes have been identified in patients with chronic wounds. In this work, we analyzed scRNA-seq datasets of normal and wounded skin from mice at day 4 post-wound to investigate fibroblast heterogeneity during the proliferative phase of wound healing. Compositional analysis revealed a specific subset of fibroblast (cluster 3) that primarily increased in wounded skin (14%) compared to normal skin (3.9%). This subset was characterized by a gene signature marked by the plasma membrane proteins Sfrp2 + Sfrp4 + Sfrp1 + and the transcription factors Ebf1 + Prrx1 + Maged1 + . Differential gene expression and enrichment analysis identified epithelial to mesenchymal transition (EMT) and angiogenesis to be upregulated in the emerging subset of fibroblasts of the wounded skin. Using two other datasets for murine wounded skin confirmed the increase in cluster 3-like fibroblasts at days 2, 7 and 14 post-wounding with a peak at day 7. By performing a similarity check between the differential gene expression profile between wounded and normal skin for this emerging fibroblast subset with drug signature from the ConnectivityMap database, we identified drugs capable of mimicking the observed gene expression change in fibroblasts during wound healing. TTNPB, verteprofin and nicotinic acid were identified as candidate drugs capable of inducing fibroblast gene expression profile necessary for wound healing. On the other hand, methocarbamol, ifosfamide and penbutolol were recognized to antagonize the identified fibroblast differential expression profile during wound healing which might cause delay in wound healing. Taken together, analysis of murine transcriptomic skin wound healing datasets suggested a subset of fibroblasts capable of inducing EMT and further inferred drugs that might be tested as potential candidates to induce wound closure.
Project description:In order to clarify the human response of re-epithelialization, we biopsied split-thickness skin graft donor site wounds immediately before and after harvesting, as well as during the healing process 3 and 7 days thereafter. Altogether 25 biopsies from 8 patients qualified for the study. All samples were analysed by genome-wide microarrays. Here we identified the genes associated with normal skin re-epithelialization on time-scale, and organized them by similarities according to their induction or suppression patterns during wound healing. Overall 25 samples were analyzed
Project description:In order to clarify the human response of re-epithelialization, we biopsied split-thickness skin graft donor site wounds immediately before and after harvesting, as well as during the healing process 3 and 7 days thereafter. Altogether 25 biopsies from 8 patients qualified for the study. All samples were analysed by genome-wide microarrays. Here we identified the genes associated with normal skin re-epithelialization on time-scale, and organized them by similarities according to their induction or suppression patterns during wound healing.