Project description:BP180, also known as collagen XVII, is a hemidesmosomal component and plays a key role in 2 maintaining skin dermal/epidermal adhesion. Dysfunction of BP180, either through genetic 3 mutations in Junctional Epidermolysis Bullosa (JEB) or autoantibody insult in Bullous Pemphigoid 4 (BP), leads to subepidermal blistering accompanied by skin inflammation. However, whether BP180 5 is involved in skin inflammation remains unknown. To address this question, we generated a BP180-6 dysfunctional mouse strain and found that mice lacking functional BP180 (termed ΔNC16A) 7 developed spontaneous skin inflammatory disease, characterized by severe itch, defective skin 8 barrier, infiltrating immune cells, elevated serum IgE levels and increased expression of thymic 9 stromal lymphopoietin (TSLP). Severe itch is independent of adaptive immunity and histamine, but 10 dependent on increased expression of TSLP by keratinocytes. Our data provide the first direct 11 evidence showing that BP180 regulates skin inflammation independently of adaptive immunity, and 12 BP180 dysfunction leads to a TSLP mediated itch.
Project description:BP180, also known as collagen XVII, is a hemidesmosomal component and plays a key role in maintaining skin dermal/epidermal adhesion. Dysfunction of BP180, either through genetic mutations in junctional epidermolysis bullosa (JEB) or autoantibody insult in bullous pemphigoid (BP), leads to subepidermal blistering accompanied by skin inflammation. However, whether BP180 is involved in skin inflammation remains unknown. To address this question, we generated a BP180-dysfunctional mouse strain and found that mice lacking functional BP180 (termed ΔNC16A) developed spontaneous skin inflammatory disease, characterized by severe itch, defective skin barrier, infiltrating immune cells, elevated serum IgE levels, and increased expression of thymic stromal lymphopoietin (TSLP). Severe itch is independent of adaptive immunity and histamine, but dependent on increased expression of TSLP by keratinocytes. In addition, a high TSLP expression is detected in BP patients. Our data provide direct evidence showing that BP180 regulates skin inflammation independently of adaptive immunity, and BP180 dysfunction leads to a TSLP-mediated itch. The newly developed mouse strain could be a model for elucidation of disease mechanisms and development of novel therapeutic strategies for skin inflammation and BP180-related skin conditions.
Project description:We conducted RNA sequencing analysis on skin tissues obtained from spontaneous inflammatory skin lesions in keratinocyte-specific Mettl3 knockout (K14CreERT2;Mettl3fl/fl) mice and their controls (Mettl3fl/fl). In brief, we observed spontaneous skin inflammation in the tail of K14CreERT2;Mettl3fl/fl mice 2-3 weeks following tamoxifen injection. The objective of this study was to investigate the impact and underlying mechanism of Mettl3 in epidermal keratinocytes regarding skin inflammation
Project description:Obesity is a major driver of type 2 diabetes (T2D) and related metabolic disorders, characterized by chronic inflammation and adipocyte dysfunction. However, the molecular triggers initiating these processes remain poorly understood. We identify FAM20C, a serine/threonine kinase, as an early obesity-induced mediator of adipocyte dysfunction. Fam20c expression is substantially upregulated in adipocytes in response to obesity, correlating with a proinflammatory transcriptional signature. Forced expression of Fam20c in adipocytes promotes robust upregulation of proinflammatory cytokines and induces insulin resistance that is dependent on its kinase activity. Conversely, deletion of adipocyte Fam20c after established obesity and hyperglycemia improves glucose tolerance, augments insulin sensitivity, and reduces visceral adiposity, without altering body weight. Phosphoproteomic studies reveal that FAM20C regulates phosphorylation of intracellular and secreted proteins, modulating pathways critical to inflammation, metabolism, and extracellular matrix remodeling. We identify FAM20C-dependent substrates, such as CNPY4, whose phosphorylation contributes to proinflammatory adipocyte signaling. Of translational relevance, we show that in humans visceral adipose FAM20C expression positively correlates with insulin resistance. Our findings establish FAM20C as an early regulator of obesity-induced adipocyte dysfunction and systemic metabolic impairment. Our studies provide proof of concept that inhibition of FAM20C may serve as a potential therapy for T2D by restoring adipocyte health.
Project description:This SuperSeries is composed of the following subset Series: GSE12248: Genetic architecture of murine skin inflammation and tumor susceptibility GSE21247: Network Analysis of Skin Tumor Progression Identifies a Rewired Genetic Architecture Affecting Inflammation and Tumor Susceptibility (carcinomas) GSE21263: Network Analysis of Skin Tumor Progression Identifies a Rewired Genetic Architecture Affecting Inflammation and Tumor Susceptibility (papillomas) GSE26273: Network Analysis of Skin Tumor Progression Identifies a Rewired Genetic Architecture Affecting Inflammation and Tumor Susceptibility (aCGH) Refer to individual Series
Project description:The maintenance of tissue-specific chronic inflammation results from the interplay of genetic and unidentified environmental factors. Here, we describe an immunoregulatory role for an environmentally driven microbial metabolite in Card14E138A/+-induced spontaneous psoriasis. Through metabolite screening, we demonstrate chronic skin inflammation is accompanied by alterations microbial metabolite. Notably, depletion of gut, not skin, microbes alleviates disease symptoms. We further identify indoxyl sulfate (I3S), a bacteriogenic metabolite, as a key driver of psoriatic inflammation and confirm that gut-resident indole-producing microbiota mediate this process. Mechanistically, indole-producing microbiota promote host I3S biothsynthesis via a metabolic relay, and I3S potentiates skin inflammation by reshaping chromatin accessibility in skin Th17 cells through AHR signaling. In human psoriasis cohorts, serum I3S levels correlate with disease severit. In summary, our study uncovers a mechanistic link between gut microbial factors and type 3 skin inflammation, highlighting targeting gut microbiota as a strategy for mitigating skin inflammation.
Project description:The maintenance of tissue-specific chronic inflammation results from the interplay of genetic and unidentified environmental factors. Here, we describe an immunoregulatory role for an environmentally driven microbial metabolite in Card14E138A/+-induced spontaneous psoriasis. Through metabolite screening, we demonstrate chronic skin inflammation is accompanied by alterations microbial metabolite. Notably, depletion of gut, not skin, microbes alleviates disease symptoms. We further identify indoxyl sulfate (I3S), a bacteriogenic metabolite, as a key driver of psoriatic inflammation and confirm that gut-resident indole-producing microbiota mediate this process. Mechanistically, indole-producing microbiota promote host I3S biothsynthesis via a metabolic relay, and I3S potentiates skin inflammation by reshaping chromatin accessibility in skin Th17 cells through AHR signaling. In human psoriasis cohorts, serum I3S levels correlate with disease severit. In summary, our study uncovers a mechanistic link between gut microbial factors and type 3 skin inflammation, highlighting targeting gut microbiota as a strategy for mitigating skin inflammation.