Project description:We performed scRNA-seq analyses on patient matched lesional and nonlesional skin from viitiligo patients using the 10x genomics platform to examine different cell populations and keratinocyte states that may contribute to vitiligo disease persistence.
Project description:Vitiligo is an acquired depigmentation of the skin inducing a marked alteration of the quality of life of affected individuals. Halting the disease progression and repigmenting the lesional skin represent the two faces of the therapeutic challenge in vitiligo. So far, none of them has been successfully addressed. Oxidative stress and immune system in genetically predisposed individuals participate to the complex pathophysiology of vitiligo. We performed a transcriptome and proteomic analysis on lesional, perilesional and non-depigmented skin of vitiligo patients compared to matched skin controls of healthy subjects. Our results show that the WNT pathway, implicated in melanocytes differentiation, was found to be altered in vitiligo skin. We demonstrated that the oxidative stress decreases WNT expression/activation in keratinocytes and in melanocytes. We developed an ex vivo skin model that remains functional up to 15 days. We then confirmed the decreased activation of the WNT pathway in human skin subjected to oxidative stress. Finally, using pharmacological agents that activate the WNT pathway, we treated the ex vivo depigmented skins from vitiligo patients and successfully induced the differentiation of resident stem cells into pre-melanocytes supporting further exploration of WNT activators to repigment vitiligo lesions. Total of 40 chips. 10 patients (3 biospies per patient: 1 lesional , 1 perilesional and 1 non lesional) ; 10 healthy volunteers (1biopsy in matched anatomical areas)
Project description:Background: Vitiligo is a chronic autoimmune skin depigmenting disorder, with a major impact on quality of life. Therapeutic options are still limited, with only one topical JAK inhibitor being FDA-approved. Although vitiligo is primarily regarded as a Th1/IFN-driven disease, emerging evidence suggests the involvement of additional immune axes, but their relevance to disease pathogenesis remains unclear. Objective: To obtain a global cutaneous transcriptomic profile of lesional and nonlesional vitiligo. Results: Robust inflammatory dysregulation was captured not only in lesional, but also nonlesional vitiligo skin relative to healthy controls. Lesional samples demonstrated upregulation of Th1 (OASL, CXCL9, CXCL10), Th2 (IL4, IL4R, CCL13, CCL17, CCL22, CCL26), and Th17/22 (IL20, S100A7, S100A8, S100A9, PI3) related markers. Similarly, nonlesional samples demonstrated activation of Th1 (CXCL9, OASL), Th2 (IL4R, IL10, CCL13, CCL17, CCL22), and Th17/22 (PI3, DEFB4A) associated markers. Clinical severity scores (VASI and/or VIDA) significantly and positively correlated with multiple inflammatory mediators (i.e., CXCL14, IL25, IL17RC) in lesional and/or nonlesional vitiligo skin. On a single-cell level, IL13 and IFNG expression were primarily found in nonlesional helper T cells and in lesional proliferating T cells, respectively. Conclusions: Our findings show that immune dysregulation in vitiligo involves immune axes beyond Th1/Tc1, with upregulation of particularly type 2 markers already in nonlesional skin, suggesting a role during early lesion formation. Capsule Summary: We suggest that the inflammatory dysregulation of vitiligo is more complex than previously appreciated, involving not only Th1, but also Th2 and some components of Th17/22 immune axes, even in clinically normal appearing skin. Clinical implications: The dysregulation of multiple inflammatory mediators in nonlesional vitiligo skin might have major implications for future targeted treatment approaches.
Project description:Vitiligo skin samples with an active inflammatory infiltrate were selected for gene expression profiling in order to identify inflammatory pathways that drive depigmentation in vitiligo. Total RNA was isolated from 10 deidentified human samples from formalin fixed, paraffin-embedded skin, 5 from vitiligo patients and 5 from controls. Control skin was age- and site-matched excision tips without pathology.
Project description:We performed single-cell RNA seq analysis on skin biopsies from six acne patients with a total of 32,966 cells from lesional skin and 29,202 cells from non-lesional skin using 10X Genomics. Gene expression data derived from cells in both lesional and non-lesional skin were aligned and projected onto a two-dimensional space using UMAP (Uniform Manifold Approximation and Projection). Unsupervised clustering revealed eight major clusters corresponding to seven different cell types lymphocytes, myeloid cells, keratinocytes, fibroblasts, endothelial cells, smooth muscle cells, and melanocytes.
Project description:We used microarry to charactarize differences in gene expression between lesional and non-lesional psoriasis skin. Our hypothethis was that IL-37 is downregulated in psoriasis.
Project description:Vitiligo skin samples with an active inflammatory infiltrate were selected for gene expression profiling in order to identify inflammatory pathways that drive depigmentation in vitiligo.
Project description:Vitiligo is an autoimmune depigmentation disorder characterized by melanocyte loss and complex immune dysregulation. Despite therapeutic advances, variable efficacy and frequent relapse highlight the need for deeper insight into its pathophysiology. Conventional 3–5 mm skin biopsies are invasive and require suturing, limiting their use in clinical and translational research. Here, we demonstrate that minimally invasive 1 mm punch biopsies yield adequate RNA compatible with bulk transcriptomic profiling and enable comprehensive molecular characterization of vitiligo skin. RNA sequencing of 105 biopsies spanning lesional, perilesional, non-lesional, and control skin revealed distinct region-specific transcriptional signatures involving interferon signaling, immune activation, and metabolic reprogramming. Beyond canonical melanocyte and immune pathways, we identify underexplored dysregulation of cellular clearance and structural regulatory mechanisms, implicating ferroptosis, peroxisome, and efferocytosis pathways in lesion persistence. Connectivity Map analysis further predicted candidate compounds capable of reversing the lesional transcriptional signature, pointing to epigenetic regulators, tyrosine kinase inhibitors, and metabolic modulators. These findings establish 1 mm skin biopsies as a feasible and biologically informative tool for minimally invasive molecular profiling and highlight new therapeutic axes in vitiligo pathogenesis.