Project description:TREX2 is a keratinocyte specific 3â-deoxyribonuclease that participates in the maintenance of skin homeostasis upon damage. This transcriptome analysis identified multiple genes and pathways deregulated by TREX2 loss in the IMQ-induced psoriasis-like model in mouse skin. mRNA sequencing of 5 biological replicates of skin from wild-type mice treated with Imiquimod and 6 of Trex2 knockout mice treated with Imiquimod
Project description:Tumor necrosis factor receptor associated factor 6 (TRAF6) is an adaptor protein that regulates NF-κB and MAPK signaling pathway and is reported to affect immune response and cell death in immune cells. However, the roles of TRAF6 in epithelium have not been well investigated. Using a mouse model of imiquimod-induced psoriasis dermatitis, we show that TRAF6 in epithelial cells totally regulates IL-17-mediated inflammation in the skin. Mice lacking TRAF6 in keratinocytes were unable to activate dendritic cells and failed to produce IL-23 or initiate IL-17 production from γδ T cells at the imiquimod-treated sites. Subcutaneous administrations of IL-23 restored IL-17 production in the mutant animals, suggesting that the induction of IL-23 production is the major TRAF6-dependent contribution of keratinocytes to this process. Therefore, the epithelial TRAF6 signaling is supposed to play an essential role in instructing and propagating the cutaneous immune response. To broadly characterize the impact of the lack of TRAF6 in keratinocytes on the skin inflammation, we analyzed gene expression in IMQ-treated whole ears of Traf6EKO mice and Traf6f/f mice using a cDNA microarray.
Project description:TREX2 is a keratinocyte specific 3’-deoxyribonuclease that participates in the maintenance of skin homeostasis upon damage. This transcriptome analysis identified multiple genes and pathways deregulated by TREX2 loss in the IMQ-induced psoriasis-like model in mouse skin.
Project description:CaMK4 has an important function in autoimmune diseases, and the contribution of CaMK4 in psoriasis remains obscure. Here, we show that CaMK4 expression is significantly increased in psoriatic lesional skin from psoriasis patients compared to healthy human skin as well as inflamed skin from an imiquimod (IMQ)-induced mouse model of psoriasis compared to healthy mouse skin. Camk4-deficient (Camk4−/−) mice treated with IMQ exhibit reduced severity of psoriasis compared to wild-type (WT) mice. There are more macrophages and fewer IL-17A+γδ TCR+ cells in the skin of IMQ-treated Camk4−/− mice compared to IMQ-treated WT mice. CaMK4 inhibits IL-10 production by macrophages, thus allowing excessive psoriatic inflammation. Deletion of Camk4 in macrophages alleviates IMQ-induced psoriatic inflammation in mice. In keratinocytes, CaMK4 inhibits apoptosis as well as promotes cell proliferation and the expression of pro-inflammatory genes such as S100A8 and CAMP. Taken together, these data indicate that CaMK4 regulates IMQ-induced psoriasis by sustaining inflammation and provides a potential target for psoriasis treatment.
Project description:Psoriasis is one of the most common dermatological disorders, characterized by increased epidermal hyperplasia and immune cell infiltration. Psychological stress has been reported to contribute to the severity, aggravation, and relapse of psoriasis. We developed a chronic restrain stress (CRS)-imiquimod (IMQ)-induced psoriasis-like mouse model and performed a comprehensive comparative transcriptomic and metabolic analysis with control mice, CRS-treated mice, and IMQ-treated mice to investigate how psychological stress affects psoriasis. We found that CRS-IMQ-induced psoriasis-like mice showed significant exacerbation of psoriasis-like skin inflammation compared with mice treated with IMQ only. Mice of the CRS+IMQ group showed increased expression of keratinocyte proliferation and differentiation genes, differential regulation of cytokines, and promotion of the linoleic acid metabolism. Our study provides new insights into the effects of psychological stress on psoriasis pathogenesis and the mechanisms involved, which provides clues for development of therapeutics or biomarkers.
Project description:We use back skin of WT SD rats, or imiquimod(IMQ)-induced psoraisis-like rat model treated with or without epidural injection of 1% lidocaine. We isolate total RNA for RNA-sequencing.
Project description:Psoriasis is a common inflammatory skin disease characterized by aberrant inflammation and epidermal hyperplasia. Molecular mechanisms that regulate psoriasis-like skin inflammation remain to be fully understood. Here we show that the expression of Ovol1 transcription factor is upregulated in psoriatic skin, and its deletion results in aggravated psoriasis-like skin symptoms following stimulation with imiquimod (IMQ). Using bulk and single-cell RNA-sequencing, we identify molecular changes in the epidermal, fibroblast and immune cells of Ovol1-deficient skin that reflect altered course of epidermal differentiation and enhanced inflammatory responses. Furthermore, we provide evidence for excessive full-length IL-1 signaling in the microenvironment of IMQ-treated Ovol1-deficient skin that functionally contributes to immune cell infiltration and epidermal hyperplasia. Collectively, our study uncovers a protective role for Ovol1 in curtailing psoriasis-like inflammation and the associated skin pathology
Project description:Imiquimod (IMQ) is a topical therapeutic immune activator that causes psoriasiform inflammation in mice. To determine if IMQ-induced inflammation and gene expression changes depended on the time of day in which treatment is administered, we performed gene expression profiling of dorsal mouse back skin by microarray after different durations of topical 1% IMQ treatment (control = no treatment, 6 hr, 24 hr, and 5 days of IMQ treatment) at different times of day (ZT01, ZT07, ZT09 = day-time treatment; ZT13 and ZT19 = night-time treatment). We also performed a time course after IMQ treatment by collecting mouse back skin after 0 (no treatment), 1, 2, 4, 6, and 24 hours post-treatment. Lastly, we determined gene expression changes in response to IMQ in mice deleted for the core circadian clock gene, Bmal1, after 0 (no treatment) and 24 hours post-1% IMQ compared to Wt (both treated and collected during the daytime at ZT09). The results of this study are important as they show that IMQ-induced activation of interferon sensitive genes are diurnal in Wt mice after 6 hours and 24 hours but not after 5 consecutive treatments. Furthermore, we find that interferon sensitive genes are induced more robustly in the skin of Bmal1 KO mice after 24 hr IMQ compared to Wt mice. These results are important for further understanding how the circadian clock regulates immune activation in response to the theraputic agent IMQ. In this dataset, we include the expression data obtained from 28 microarray samples, all of which were generated from whole back skin RNA samples pooled from 5-7 mice per sample.