Longitudinal single cell RNA-seq of the inflamed colon
Ontology highlight
ABSTRACT: We demonstrate single-cell RNA sequencing with time course study on DSS-induced colitis mouse model to reveal the overall cellular status during colon inflammation. Based on single cell transcriptome analysis in inflamed colon, we showed that the stromal cell population of colon functions as a hub to coordinate dynamic change with other cell type. We also found the Serpina3n, a serine protease inhibitor is specific up-regulation in the stromal cells during the resolution phase of colon inflammation. Furthermore, we found that systemic administration of Serpina3n promoted the recovery of resolution phase and ameliorated colitis-related symptoms. This study provides a comprehensive understanding of cell-cell interactions during colorectal inflammation at the single-cell level and reveals a potential therapeutic target by hijacking the endogenous inflammation resolution mechanism.
Project description:Inflammation dramatically alters the gut microenvironment. To investigate the composition and transcriptome changes of various intestinal cell populations during the initial phase of inflammation, and the underlying cellular interactions, we delineated a single-cell atlas of the mouse colon treated with DSS on the day 2 of colitis.
Project description:Chronic inflammation underlies tumor initiation, progression, invasion, and metastasis. In the colon, long-term exposure to chronic inflammation drives colitis associated colon cancer (CAC) in patients with inflammatory bowel disease (IBD). While the causal and clinical links between chronic inflammation and CAC are well established, our molecular understanding of how chronic inflammation leads to the development of colon cancer is still lacking. Here we deconstruct the evolving microenvironment of CAC, by measuring proteomic changes and extracellular matrix (ECM) organization over time in a genetically modified mouse model of CAC. We detect early changes in ECM structure and composition, and report that the transcriptional regulator heat shock factor 1 (HSF1) plays a crucial role in orchestrating these events. Activated in stromal fibroblasts of the gut, HSF1 promotes ECM remodeling and inflammatory programs which lead to the development of CAC. Loss of HSF1 abrogates ECM assembly by colon fibroblasts in cell culture, prevents inflammation-induced ECM remodeling in mice and significantly inhibits progression to CAC. Establishing the relevance of our experimental findings to human disease, we find high activation of stromal HSF1 in CAC patients, and detect the HSF1-dependent proteomic ECM signature in human colorectal cancer. Thus, HSF1-dependent ECM remodeling plays a crucial role in mediating inflammation-driven colon cancer.
Project description:IL17B protected mice from dextran sodium sulfate (DSS)-induced colitis since IL17B deficiency resulted in severe DSS-induced colitis with exaggerated weight loss, shorter colon length, and elevated proinflammatory cytokine production in colon. For mechanism study, we use single cell transcriptional analyses of CD45+ immune cells in colonic lamina propria to detect the effect of IL-17B on colon LP immune cells in colitis. We found increased inflammatory macrophages infiltration in colon lamina propria after colitis induction expressing inflammatory cytokines such as S100a9, S100a8, Tnf, which was confirmed by real-time PCR and flow cytometry. Reconstitute of Il17b-/- mice with recombinant IL17B alleviated the severity of DSS-induced colitis. IL17B treatment also inhibited LPS-induced inflammation in bone marrow derived macrophage and in mice. These data indicate that IL17B exerting its inhibitory role in inflammation by regulating inflammatory macrophage response. In view of the protective effect of IL17B on DSS-induced colitis and LPS-induced inflammation, IL17B might represent a novel potential therapeutic approach to treat the inflammation.
Project description:IL17B protected mice from dextran sodium sulfate (DSS)-induced colitis since IL17B deficiency resulted in severe DSS-induced colitis with exaggerated weight loss, shorter colon length, and elevated proinflammatory cytokine production in colon. For mechanism study, we use single cell transcriptional analyses of CD45+ immune cells in colonic lamina propria to detect the effect of IL-17B on colon LP immune cells in colitis. We found increased inflammatory macrophages infiltration in colon lamina propria after colitis induction expressing inflammatory cytokines such as S100a9, S100a8, Tnf, which was confirmed by real-time PCR and flow cytometry. Reconstitute of Il17b-/- mice with recombinant IL17B alleviated the severity of DSS-induced colitis. IL17B treatment also inhibited LPS-induced inflammation in bone marrow derived macrophage and in mice. These data indicate that IL17B exerting its inhibitory role in inflammation by regulating inflammatory macrophage response. In view of the protective effect of IL17B on DSS-induced colitis and LPS-induced inflammation, IL17B might represent a novel potential therapeutic approach to treat the inflammation.
Project description:Ulcerative Colitis is an autoimmune inflammatory bowel disease that causes chronic inflammation in the colon and the rectum. Althoung extensively researched, the underlying molecular mechanisms of Ulcerative Colitis remain elusive. Especially, there is a lack of understanding about regulatory non-coding miRNA expression during Ulcerative Colitis in a cell type-specific context. Therefore, we performed high-throughput miRNA profiling of Fluorescence Activated Cell Sorting (FACS)-enriched CD66a+ and CD44+ colonic epithelial cell populations from colon tissue biopsies of 16 patients with active Ulcerative Colitis, 15 patients with quiescent Ulcerative Colitis and 17 Symptomatic Control individuals.
Project description:Mature myeloid cells play a crucial role in the pathogenesis of Crohn disease (CD) but the molecular players that regulate their functions in CD are not fully characterized. Here we show that Trim33 mRNA level is decreased in CD patient’s blood monocytes and characterize TRIM33 functions in monocytes during dextran sulfate sodium (DSS) induced colitis. Mice deleted for trim33 only in mature myeloid cells (Trim33-/- mice) display an impaired resolution of colonic inflammation. This deficiency is associated with an increased number of blood and colon neutrophils and monocytes and a decreased number of colonic macrophages. In accordance, Trim33-/- monocytes are less competent that wild type monocytes for recruitment and differentiation into macrophages at the inflammatory site. Furthermore, during resolution of DSS-induced colitis, Trim33-/- colonic macrophages display an impaired M1/M2 switch and express a low level of membrane bound TNFα known to regulate resolution of inflammation. Altogether, these results show an important role of TRIM33 in monocytes/macrophages during the resolution of DSS-induced colonic inflammation and pinpoint TRIM33 as a novel Crohn disease biomarker and as a potential therapeutic target.
Project description:Background: Immune cell populations within the intestinal muscularis propria are poorly resolved during colitis. Maintaining homeostasis in this unique niche is of critical importance, highlighted by the poorer prognosis of inflammatory bowel disease associated with inflammation in the muscularis propria. Methods: This study utilizes single-cell RNA sequencing to survey the immune cell populations within the muscularis propria of normal colon and DSS-induced colitis. Results: In naïve conditions, transcriptional duality is observed in MMφ with two major supopulations: conventional resident Cx3cr1+ MMφs and Lyve1+ MMφs. During colitis, significant changes occur within the muscularis propria, with increases in B-cells, T-cells, monocytes, neutrophils, and dendritic cells. Unlike in the mucosa, single cell transcriptomics indicates that resident MMφs are retained during colitis and exhibit plasticity toward an inflammatory profile. Lyve1+ MMφs, which express anti-inflammatory marker CD163, are absent during colitis. In contrast, resident Cx3cr1+ MMφs remain during colitis. Conclusions: Our findings provide a resource for understanding the immune system in the muscularis propria niche during colitis and resolve the heterogeneity and origins of proinflammatory MMφs during colitis by demonstrating the plasticity of the persistent MMφ population.
Project description:Ulcerative Colitis is an autoimmune inflammatory bowel disease that causes chronic inflammation in the colon and the rectum. Althoung extensively researched, the underlying molecular mechanisms of Ulcerative Colitis remain elusive. Especially, there is a lack of understanding about regulatory non-coding miRNA expression during Ulcerative Colitis. Therefore, we performed high-throughput miRNA profiling of colon tissue biopsies from XX patients with active Ulcerative Colitis, XX patients with quiescent Ulcerative Colitis and XX Symptomatic Control individuals.
Project description:Ulcerative colitis (UC) is a chronic inflammatory condition of the colon, driven by mucosal immune and stromal subsets, culminating in epithelial injury. Vedolizumab (VDZ) is an anti-integrin monoclonal antibody that is effective for treating UC. VDZ is known to inhibit lymphocyte trafficking to the intestine, but its broader effects on other cell subsets are less defined. To identify the inflammatory cells that contribute to colitis and are affected by VDZ, we performed a single-cell and spatial transcriptomic and proteomic analysis of peripheral blood and colonic biopsies in healthy controls (HC) and patients with UC on VDZ or other therapies. We identified significant effects of VDZ on mononuclear phagocyte (MNP) subsets, in addition to modest effects on lymphocyte populations. Spatial transcriptomics and proteomics of formalin-fixed, paraffin-embedded (FFPE) biopsies at single-cell resolution demonstrated trends towards increased abundance and proximity of activated MNP and fibroblast subsets in active colitis compared to HC, with inhibition by VDZ. Spatial transcriptomics of archived FFPE specimens pre-treatment identified epithelial-, MNP-, and fibroblast-enriched genes related to VDZ response versus non-response, and these were validated in an external, publicly accessible bulk transcriptomic dataset. Single cell and spatial multi-omics highlight important roles for myeloid, stromal, and epithelial subsets in UC.
Project description:Ulcerative colitis (UC) is a chronic inflammatory condition of the colon, driven by mucosal immune and stromal subsets, culminating in epithelial injury. Vedolizumab (VDZ) is an anti-integrin monoclonal antibody that is effective for treating UC. VDZ is known to inhibit lymphocyte trafficking to the intestine, but its broader effects on other cell subsets are less defined. To identify the inflammatory cells that contribute to colitis and are affected by VDZ, we performed a single-cell and spatial transcriptomic and proteomic analysis of peripheral blood and colonic biopsies in healthy controls (HC) and patients with UC on VDZ or other therapies. We identified significant effects of VDZ on mononuclear phagocyte (MNP) subsets, in addition to modest effects on lymphocyte populations. Spatial transcriptomics and proteomics of formalin-fixed, paraffin-embedded (FFPE) biopsies at single-cell resolution demonstrated trends towards increased abundance and proximity of activated MNP and fibroblast subsets in active colitis compared to HC, with inhibition by VDZ. Spatial transcriptomics of archived FFPE specimens pre-treatment identified epithelial-, MNP-, and fibroblast-enriched genes related to VDZ response versus non-response, and these were validated in an external, publicly accessible bulk transcriptomic dataset. Single cell and spatial multi-omics highlight important roles for myeloid, stromal, and epithelial subsets in UC.