The mechanisms of inflammation in acne are not well understood. This study performed in two separate patient populations focused on the activation of adaptive and innate immunity in early inflamed acne. Biopsies were collected from lesional and non-lesional skin of acne patients. Psoriasis patients and healthy volunteers were included in the study for comparison (not included in the records). Using Affymetrix Genechips, we observed significant elevation of the signature cytokines of the Th17 lineage in acne lesions compared to non-lesional skin. The increased expression of IL-17 was confirmed with real-time qPCR (RT-PCR) in two separate patient populations. Cytokines involved in Th17 lineage differentiation (IL-1beta, IL-6, TGF-beta; IL23p19) were remarkably induced at the RNA level. In addition, pro-inflammatory cytokines (IL-8, TNF-), Th1 markers (IL12p40, CXCR3, T-bet, IFN-gamma), T regulatory cell markers (Foxp3, IL-10, TGF-) and antimicrobial peptides (S100A7, S100A9, LNC2, hBD2, hBD3, hCAP18) were induced. Importantly, immunohistochemistry revealed significantly increased numbers of IL-17A positive T cells and CD83 dendritic cells in the acne lesions. In summary our results demonstrate the presence of IL17A positive T cells and the activation of Th17-related cytokines in acne lesions, indicating that the Th17 pathway may play a pivotal role in the disease process, offering new targets of therapy.
IL-17/Th17 pathway is activated in acne lesions.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Nuclear hormone 1α,25-dihydroxyvitamin D3 elicits a genome-wide shift in the locations of VDR chromatin occupancy.
Specimen part, Cell line, Treatment
View SamplesIdentification of primary target genes of vitamin D receptor (VDR) in an immune-related cellular model (THP-1 cells) to study, in conjunction with VDR binding data from ChIP-seq, the genome-wide mechanisms of transcriptional regulation by VDR.
Nuclear hormone 1α,25-dihydroxyvitamin D3 elicits a genome-wide shift in the locations of VDR chromatin occupancy.
Specimen part, Cell line, Treatment
View SamplesThe transcription factor Peroxisome Proliferator-Activated Receptor (PPAR) is an important regulator of hepatic lipid metabolism. While PPAR is known to activate transcription of numerous genes, no comprehensive picture of PPAR binding to endogenous genes has yet been reported. To fill this gap, we performed ChIP-chip in combination with transcriptional profiling on HepG2 human hepatoma cells treated with the PPAR agonist GW7647. We found that GW7647 increased PPAR binding to 4220 binding regions. GW7647-induced binding regions showed a bias around the transcription start site and most contained a predicted PPAR binding motif. Several genes known to be regulated by PPAR, such as ACOX1, SULT2A1, ACADL, CD36, IGFBP1 and G0S2, showed GW7647-induced PPAR binding to their promoter. A GW7647-induced PPAR-binding region was also assigned to SREBP-targets HMGCS1, HMGCR, FDFT1, SC4MOL, and LPIN1, expression of which was induced by GW7647, suggesting cross-talk between PPAR and SREBP signaling. Our data furthermore demonstrate interaction between PPAR and STAT transcription factors in PPAR-mediated transcriptional repression, and suggest interaction between PPAR and TBP and C/EBP in PPAR-mediated transcriptional activation. Overall, our analysis leads to important new insights into the mechanisms and impact of transcriptional regulation by PPAR in human liver and highlight the importance of cross-talk with other transcription factors.
Profiling of promoter occupancy by PPARalpha in human hepatoma cells via ChIP-chip analysis.
Specimen part, Cell line, Treatment
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