Project description:Background: Atopic dermatitis (AD) is a common inflammatory skin disease with broad impact on quality of life and on the health care system. The pathophysiology is not fully understood, but it is likely multifactorial involving immune dysfunction, altered skin barrier and environmental factors. Narrow band ultraviolet B (nb-UVB) treatment leads to normalization of the tissue and clinical improvement. However, knowledge of early changes in AD skin in response to nb-UVB is lacking and could provide important clues to decipher the disease mechanisms and potential new treatment targets. Objective: To map the early transcriptional changes in the skin in response to nb-UVB treatment. Results: When examining the early response after only three local UVB-treatments, gene expression analysis revealed 30 down- and 47 up-regulated transcripts. Among these only a small proportion were related to the inflammatory response. Interestingly, two cytokines of the interleukin (IL)-1 family were differentially expressed: the proinflammatory cytokine IL-36γ was reduced after treatment, while the anti-inflammatory cytokine IL-37 increased in skin after treatment with nb-UVB. Conclusion: Local nb-UVB induced an early decrease of the pro-inflammatory cytokine IL-36γ and an increase of the anti-inflammatory IL-37. This likely represents one of the first changes in inflammatory signaling induced by nb-UVB in atopic eczema.
Project description:Background: Atopic dermatitis (AD) is a common inflammatory skin disease exhibiting a predominantly Th2/"T22" immune activation and a defective epidermal barrier. Narrow-band UVB (NB-UVB) is considered an efficient treatment for moderate to severe AD. In psoriasis, NB-UVB has been found to suppress the Th1/Th17 immune polarization with subsequent reversal of epidermal hyperplasia. The immunomodulatory effects of this treatment are largely unknown in AD. Our study evaluates the effects of NB-UVB on immune and barrier abnormalities in AD, aiming to establish reversibility of disease and biomarkers of therapeutic response. Methods: 12 moderate-to-severe chronic AD patients received NB-UVB phototherapy 3 times weekly for up to 12 weeks. Lesional and non-lesional skin biopsies were obtained before and after treatment and evaluated by gene-expression and immunohistochemistry studies. Results: All patients had at least a 50% reduction in SCORing of AD (SCORAD) index with NB-UVB phototherapy. The Th2, T22, and Th1 immune pathways were suppressed and measures of epidermal hyperplasia and differentiation also normalized after phototherapy. The reversal of disease activity was associated with elimination of inflammatory leukocytes, Th2/"T22"-associated cytokines and chemokines, and normalized expression of barrier proteins. Conclusions: Our study shows reversal of both the epidermal defects and underlying immune activation in AD. By determining the correlation of variables with therapeutic response, we have defined a set of biomarkers of disease response that associate resolved Th2 and T22 inflammation with reversal of barrier pathology. This data supports the "inside-out" hypothesis of AD, suggesting that it is a disease primarily driven by an immune stimulus. genomic profiling of treatment effect of NB-UVB in AD in both lesional and non-lesional AD skin from 10 patients. Treatment effect, disease state analysis
Project description:Background: Atopic dermatitis (AD) is a common inflammatory skin disease exhibiting a predominantly Th2/“T22” immune activation and a defective epidermal barrier. Narrow-band UVB (NB-UVB) is considered an efficient treatment for moderate to severe AD. In psoriasis, NB-UVB has been found to suppress the Th1/Th17 immune polarization with subsequent reversal of epidermal hyperplasia. The immunomodulatory effects of this treatment are largely unknown in AD. Our study evaluates the effects of NB-UVB on immune and barrier abnormalities in AD, aiming to establish reversibility of disease and biomarkers of therapeutic response. Methods: 12 moderate-to-severe chronic AD patients received NB-UVB phototherapy 3 times weekly for up to 12 weeks. Lesional and non-lesional skin biopsies were obtained before and after treatment and evaluated by gene-expression and immunohistochemistry studies. Results: All patients had at least a 50% reduction in SCORing of AD (SCORAD) index with NB-UVB phototherapy. The Th2, T22, and Th1 immune pathways were suppressed and measures of epidermal hyperplasia and differentiation also normalized after phototherapy. The reversal of disease activity was associated with elimination of inflammatory leukocytes, Th2/“T22”-associated cytokines and chemokines, and normalized expression of barrier proteins. Conclusions: Our study shows reversal of both the epidermal defects and underlying immune activation in AD. By determining the correlation of variables with therapeutic response, we have defined a set of biomarkers of disease response that associate resolved Th2 and T22 inflammation with reversal of barrier pathology. This data supports the “inside-out” hypothesis of AD, suggesting that it is a disease primarily driven by an immune stimulus.
Project description:mRNA array analysis of total RNA from primary kertinocytes from three healthy controls, three atopic dermatitis patients and three psoriasis patients was carried out
Project description:Clinical overlaps between psoriasis and atopic dermatitis are sometimes undiscernible, and there is no consensus whether to treat the overlap phenotype as psoriasis or atopic dermatitis. We enrolled patients diagnosed with either psoriasis or atopic dermatitis, and clinically re-stratified them into classic psoriasis, classic atopic dermatitis, and the overlap phenotype between psoriasis and atopic dermatitis. We compared gene expression profiles of lesional and nonlesional skin biopsy tissues between the three comparison groups. Global mRNA expression and T-cell subset cytokine expression in the skin of the overlap phenotype were consistent with the profiles of psoriasis and different from the profiles of atopic dermatitis. Unsupervised k-means clustering indicated that the best number of distinct clusters for the total population of the three comparison groups was two, and the two clusters of psoriasis and atopic dermatitis were differentiated by gene expression. Our study suggests that clinical overlap phenotype between psoriasis and atopic dermatitis has dominant molecular features of psoriasis, and genomic biomarkers can differentiate psoriasis and atopic dermatitis at molecular levels in patients with a spectrum of psoriasis and atopic dermatitis.
Project description:Characteization host-microbiome interactions in patients with allergic (model: atopic dermatitis) and autoimmune (model: psoriasis) diseases by integration of microarray transcriptome data with 16S microbial profiling. 6mm punch biopsies were collected from the skin of atopic dermatitis and psoriasis patients alongside healthy volunteers, and subjected to analysis using Affymetrix Human Gene ST 2.1 arrays.
Project description:Atopic dermatitis is increasing worldwide, correlating with air pollutions. Various organic components of pollutants activate transcription factor AhR (aryl-hydrocarbon receptor). We have established AhR-CA mice, whose keratinocytes express constitutive-active AhR, and these mice developed atopic dermatitis-like frequent scratching and allergic inflammation. In this study we performed ChIP-seq analyses and identified keratinocyte-specific AhR target genes, including inflammatory cytokines Tslp and IL33, and neurotrophic factor Artemin. While AhR-CA mice exhibited epidermal hyperinnervation and alloknesis leading to hypersensitivity to pruritus, blockade of Artemin alleviated these phenotypes. AhR-CA mice showed scratching-induced barrier insufficiency and enhanced sensitization to epicutaneously-applied antigens, recapitulating human atopic dermatitis. Consistently, AhR activation and Artemin expression was detected in the epidermis of atopic dermatitis patients and keratinocytes exposed to air pollutants. Thus, AhR in keratinocytes senses the environmental stimuli and responds to them through moderating inflammation. We propose a mechanism in which air pollution induces atopic dermatitis through AhR activation.
Project description:Lipids play a critical role in the skin as components of the epidermal barrier and as sig-naling molecules. Atopic dermatitis in dogs is associated with changes in the lipid composition of the skin, but whether these precede the onset of dermatitis or occur secondary to the dermatitis is unclear. We applied rapid lipid profiling mass spectrometry methods to skin and blood samples of dogs and determined changes following systemic treatment. Thirty control dogs and 30 atopic dogs with mild to moderate dermatitis were enrolled. Marked differences in lipid profiles were observed between control, nonlesional and lesional skin of dogs. Additionally, there were significant altera-tions in the lipid composition of the blood samples indicating systemic changes in lipid metabolism. Treatment with oclacitinib or lokivetmab resulted in a significant decrease of the disease clinical severity associated with changes in skin and blood lipids. A set of lipid features of the skin were selected as biomarkers that classified samples as control or atopic dermatitis with 95% accuracy, whereas blood lipids discriminated between control and atopic dogs with 82% accuracy. These data suggest that atopic dermatitis is a systemic disease and support the use of rapid lipid profiling to identify novel biomarkers.