ABSTRACT: Comparison of gene expression in atopic dermatitis (AD) and ichthyosis vulgaris (IV) patients skin compared to healthy control skin depending on filaggrin(FLG) genotype
Project description:Disrupted skin barrier due to altered keratinocyte differentiation is common in pathologic conditions such as atopic dermatitis, ichthyosis and psoriasis. However, the molecular cascades governing keratinocyte terminal differentiation are still poorly understood. We have previously demostrated that a dominante mutation in ZNF750 leads to a clinical phenotype that reminiscent of psoriasis and seborrehic dermatitis. We defined ZNF750 as a nuclear effector that is atrongly activated in and essiential for keratinocyte terminal differentiation. ZNF750 knockdown in HaCaT keratinocytes markedly reduced the expression of epidermal late differentiation markers, including gene subsets of epidermal differentiation complex and skin barrier formation such as FLG, LOR, SPINK5, ALOX12B and DSG1, known to be mutated in various human skin diseases. Furthermore, ZNF750 over-expression in undifferentiated cells induced terminal differentiation genes. Thus, ZNF750 is a regulator of keratinocyte terminal differnetiation, and with its downstream targets can serve in future elucidation of therapeutics for common disease of skin barrier Gene expression analysis: To determine the differentaition signature for HaCaT keratinocytes, with ZNF750 gene silencing, total RNA was isolated in biologic triplicates from cells induced to differentiate for twelve days and hybridized to Affymerix Human Gene 1.0 ST arrays.
Project description:Previous transcriptome analyses confirmed the major role of immunological and skin barrier abnormalities in atopic dermatitis (AD). We here aimed at identifying novel pathogenic pathways involved in AD by comparing AD patients stratified for filaggrin (FLG) mutations not only to healthy donors but also to patients with ichthyosis vulgaris (IV). We applied single-molecule direct RNA-sequencing to analyze the whole transcriptome of nonlesional skin. Six hundred and one genes (478 up-regulated and 123 down-regulated by greater than 2-fold) were differentially expressed when all AD patients were compared to healthy donors. Expression of genes involved in RNA/protein synthesis, RNA splicing, and ATP synthesis was enhanced. Interestingly, genes involved in cell death, response to oxidative stress, DNA damage/repair and xenobiotic metabolism were largely enriched. Two hundred and thirty-seven genes (216 up-regulated and 21 down-regulated by greater than 2-fold) were altered in the skin of IV patients when compared to healthy donors. Remarkably, enhancement of xenobiotic metabolism was only detected in AD skin. Moreover, increased expression of genes encoding for keratinocyte cross-linking (SPRR2) and S100 proteins characterizes the skin of patients with AD flare when compared to patients without. We did not find significant differences in gene profiling between AD patients with and without FLG mutations.This work reveals new putative pathogenic pathways related to xenobiotic metabolisms involved in AD.
Project description:The purpose of this study was to analyze the genomic signatures and profiles of skin from ichthyosis (various subtypes) vs. healthy patients. The analysis strategy was to study differentially expressed genes common to the ichthyosis shared phenotype, as well as individual ichthyosis subtypes, and compare and contrast to the genomic profiles of atopic dermatitis and psoriasis.
Project description:Disrupted skin barrier due to altered keratinocyte differentiation is common in pathologic conditions such as atopic dermatitis, ichthyosis and psoriasis. However, the molecular cascades governing keratinocyte terminal differentiation are still poorly understood. We have previously demonstrated that a dominant mutation in ZNF750 leads to a clinical phenotype that reminiscent of psoriasis and seborrheic dermatitis. We defined ZNF750 as a nuclear effector that is strongly activated in and essential for keratinocyte terminal differentiation. ZNF750 knockdown in HaCaT keratinocytes markedly reduced the expression of epidermal late differentiation markers, including gene subsets of epidermal differentiation complex and skin barrier formation such as FLG, LOR, SPINK5, ALOX12B and DSG1, known to be mutated in various human skin diseases. Furthermore, ZNF750 over-expression in undifferentiated cells induced terminal differentiation genes. Thus, ZNF750 is a regulator of keratinocyte terminal differentiation, and with its downstream targets can serve in future elucidation of therapeutics for common disease of skin barrier
Project description:In this study we used genomic profiling to characterize differences in expression of genes related to epidermal growth/differentiation and inflammatory circuits in skin lesions of psoriasis and atopic dermatitis (AD), comparing expression values to normal skin. Skin biopsies were collected from 9 patients with chronic atopic dermatitis, 15 psoriasis patients, and 9 healthy volunteers. Keywords: Genetic-pathology
Project description:The skin barrier is vital for protection against environmental threats including insults caused by skin-resident microbes. Dysregulation of this barrier is a hallmark of atopic dermatitis (AD) and ichthyosis, with variable consequences for host immune control of colonizing commensals and opportunistic pathogens. While Malassezia is the most abundant commensal fungus of the skin, little is known about the host control of this fungus in inflammatory skin diseases. Here we show that in barrier-impaired skin, Malassezia acquires enhanced fitness and overt growth properties. By using four distinct and complementary murine models of atopic dermatitis and ichthyosis we provide evidence that structural and metabolic changes in the dysfunctional epidermal barrier environment provide increased accessibility and an altered lipid profile, to which the lipid-dependent yeast adapts for enhanced nutrient assimilation. These findings reveal fundamental insights into the implication of the mycobiota in the pathogenesis of common skin barrier disorders.
Project description:In this study we used genomic profiling to characterize differences in expression of genes related to epidermal growth/differentiation and inflammatory circuits in skin lesions of psoriasis and atopic dermatitis (AD), comparing expression values to normal skin. Skin biopsies were collected from 9 patients with chronic atopic dermatitis, 15 psoriasis patients, and 9 healthy volunteers. Keywords: Genetic-pathology Psoriasis and AD are common inflammatory skin diseases which share important features, including: 1) large infiltrates of T-cells and inflammatory dendritic cells in skin lesions, 2) immune activation with up-regulated expression of many cytokines, chemokines, and inflammatory molecules 3) marked epidermal hyperplasia in chronic diseased skin and 4) defective barrier function with increased transepidermal water loss (TEWL), which reflects underlying alterations in keratinocyte differentiation. Using genomic profiling we provide a comprehensive comparison of chronic psoriasis and AD skin lesions as compared with normal skin.
Project description:Flaky tail mice (FTM) with gene mutations to FLG and TMEM79 are known to spontaneously develop atopic dermatitis (AD)-like dermatitis with age. Interestingly, we have already reported that the spontaneous development of dermatitis exhibits site-specificity, i. e. , the face and neck develop spontaneous dermatitis, while the dorsal flank shows normal skin in old FTM. In fact, transepidermal water loss and stratum corneum (SC) pH increased, SC hydration decreased, and epidermis thickened in the neck, but not in the dorsal flank. The detailed pathogenic mechanisms of such site-specific emergence of dermatitis in FTM remain unclear. To clarify the pathogenesis of site-specificity, we analyzed skin of the neck and flank in old FTM using a microarray.