Project description:GPR43 is a short-chain fatty acid receptor exerting anti-inflammatory functions in various inflammatory diseases. Even though eosinophils are one of the cell types highly expressing GPR43, the role of GPR43 in regulating eosinophils has not been studied. In this experiment, we compared transcriptomic profiles of control (Epx-Cre/+) and GPR43-deficient (Epx-Cre/+GPR43fl/fl) eosinophils purified from asthmatic lungs using bulk RNA sequencing.
Project description:GPR43 is a short-chain fatty acid receptor exerting anti-inflammatory functions in various inflammatory diseases. Even though eosinophils are one of the cell types highly expressing GPR43, the role of GPR43 in regulating eosinophils has not been studied. In this experiment, we induced asthma in control (Epx-Cre/+) mice and eosinophil-specific GPR43-deficient (Epx-Cre/+GPR43fl/fl) mice using house dust mite extracts and compared the immune cell landscape in the asthmatic lungs of each group using single-cell RNA sequencing.
Project description:During inflammation immune cells can induce endothelial activation and angiogenesis by cytokines and other mediators1,2. The inhibition of inflammation-associated angiogenesis ameliorates inflammatory diseases by reducing the recruitment of tissue infiltrating leukocytes3-5. However, there is limited evidence on initial mechanisms of both processes. Here we show that angiogenesis precedes leukocyte infiltration during graft-versus-host disease (GVHD) and experimental colitis. A key feature of GVHD is the incompletely understood organ tropism to skin, liver and the intestines. We found that angiogenesis initiates GVHD in target organs whereas in non-target organs no angiogenesis and no subsequent inflammation occur, suggesting a previously unrecognized role of the endothelium in GVHD organ tropism. The initiation phase of angiogenesis was not associated to classical endothelial cell (EC) activation signs, such as Vegfa/VEGFR1+2 upregulation or increased adhesion molecule expression. In gene array- and proteomic analyses, we found significant metabolic and cytoskeleton changes in ECs leading to profoundly higher deformation in real-time deformability cytometry6. Our results demonstrate that metabolic changes trigger enhanced migratory and proliferating potential of ECs during the initiation of angiogenesis in GVHD target organs. Our study adds evidence to the hypothesis that angiogenesis can initiate inflammation and provides novel insight in pathophysiology and tropism of GVHD.
Project description:To uncover the role of opioid induced dysbiosis in disrupting intestinal homeostasis, we conducted a multi-omics analysis with gut microbial, metabolite and intestinal transcriptomics data
Project description:To uncover the role of opioid induced dysbiosis in disrupting intestinal homeostasis, we conducted a multi-omics analysis with gut microbial, metabolite and intestinal transcriptomics data
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.
Project description:Steroid-refractory gastrointestinal graft-versus-host disease (GI GVHD) is a major barrier to successful hematopoietic stem cell transplant (HSCT). Poor understanding of the pathophysiology of GI GVHD contributes to continued poor outcomes and high mortality rates. We therefore obtained rectosigmoidal mucosal biopsies from post-HSCT patients with GI GVHD and submitted them to RNA-sequencing in order to transcriptomally characterize GI GVHD. These were compared to patients undergoing endoscopy for routine clinical indications. Using single end, 50bp reads processed using Kallisto using genome annotations from Gencode v24 with transcripts per million as the output. We included 14,239 trancsripts in our analysis, where we compared GVHD vs non-GVHD with significance defined as FDR<0.05 and FC 1.5 using R package DESeq2. We identified 164 key genes, of which 141 were upregulated in GVHD, and were ontologically related to microbial response, key immune effectors, and cell migration/chemotaxis. Down-regulated genes were related to nutrient metabolism. Additionally, we performed WGCNA that highlighted ERK as a key upregulated pathway in GI GVHD.