ABSTRACT: Transcription profiling of bone marrow-derived macrophages from colitis-resistant and colitis-susceptible interleukin-10-deficient strains stimulated with Cbir-flagellin
Project description:Background and Aims: In the interleukin-10-deficient (Il10-/-) mouse model of IBD, 10 quantitative trait loci (QTL) have been shown to be associated with colitis susceptibility by linkage analyses on experimental crosses of highly susceptible C3H/HeJBir (C3Bir)-Il10-/- and partially resistant C57BL/6J (B6)-Il10-/- mice. The strongest locus (C3Bir-derived cytokine deficiency-induced colitis susceptibility [Cdcs]1 on Chromosome [Chr] 3) controlled multiple colitogenic subphenotypes and contributed the vast majority to the phenotypic variance in cecum and colon. This was demonstrated by interval-specific Chr 3 congenic mice wherein defined regions of Cdcs1 from C3Bir or B6 were bred into the IL-10-deficient reciprocal background and altered the susceptible or resistant phenotype. Furthermore, this locus likely acts by inducing innate hypo- and adaptive hyperresponsiveness, associated with impaired NFΚB responses of macrophages. The aim of the present study was to dissect the complexity of Cdcs1 by further development and characterization of reciprocal Cdcs1 congenic strains and to identify potential candidate genes in the congenic interval. Material and Methods: In total, 15 reciprocal congenic strains were generated from Il10-/- mice of either C3H/HeJBir or C57BL/6J backgrounds by 10 cycles of backcrossing. Colitis activity was monitored by histological grading. Candidate genes were identified by fine mapping of congenic intervals, sequencing, microarray analysis and a high-throughput real-time RT-PCR approach using bone marrow-derived macrophages. Results: Within the originally identified Cdcs1-interval, three independent regions were detected that likely contain susceptibility-determining genetic factors (Cdcs1.1, Cdcs1.2, and Cdcs1.3). Combining results of candidate gene approaches revealed Fcgr1, Cnn3, Larp7, and Alpk1 as highly attractive candidate genes with polymorphisms in coding or regulatory regions and expression differences between susceptible and resistant mouse strains. Conclusions: Subcongenic analysis of the major susceptibility locus Cdcs1 on mouse chromosome 3 revealed a complex genetic structure. Candidate gene approaches revealed attractive genes within the identified regions with homologs that are located in human susceptibility regions for IBD. Experiment Overall Design: Bone marrow derived macrophages (BMDM) of colitis susceptible C3Bir-Il10-/- and colitis resistant B6-Il10-/- as well as the Il10-/- reciprocal congenic strains CB-R1 (C3Bir genetic background carrying a long congenic chromosome 3 element containing Cdcs1 from B6, rendering this formerly susceptible background resistant) and BC-R3 (B6 genetic background that carries the Cdcs1-region of C3Bir) were cultured and stimulated with flagellin or left unstimulated. BMDM were obtained from 3 male mice per genotype and cultured in polystyrene 6-well culture plates. Before RNA-isolation, 3 wells per plate were stimulated with Cbir1 flagellin (and subsequently pooled for RNA isolation), the other 3 wells left unstimulated (and also pooled). In total, these experiments were replicated three times in order to perform microarray analyses in triplicates.
Project description:Background and Aims: In the interleukin-10-deficient (Il10-/-) mouse model of IBD, 10 quantitative trait loci (QTL) have been shown to be associated with colitis susceptibility by linkage analyses on experimental crosses of highly susceptible C3H/HeJBir (C3Bir)-Il10-/- and partially resistant C57BL/6J (B6)-Il10-/- mice. The strongest locus (C3Bir-derived cytokine deficiency-induced colitis susceptibility [Cdcs]1 on Chromosome [Chr] 3) controlled multiple colitogenic subphenotypes and contributed the vast majority to the phenotypic variance in cecum and colon. This was demonstrated by interval-specific Chr 3 congenic mice wherein defined regions of Cdcs1 from C3Bir or B6 were bred into the IL-10-deficient reciprocal background and altered the susceptible or resistant phenotype. Furthermore, this locus likely acts by inducing innate hypo- and adaptive hyperresponsiveness, associated with impaired NFΚB responses of macrophages. The aim of the present study was to dissect the complexity of Cdcs1 by further development and characterization of reciprocal Cdcs1 congenic strains and to identify potential candidate genes in the congenic interval. Material and Methods: In total, 15 reciprocal congenic strains were generated from Il10-/- mice of either C3H/HeJBir or C57BL/6J backgrounds by 10 cycles of backcrossing. Colitis activity was monitored by histological grading. Candidate genes were identified by fine mapping of congenic intervals, sequencing, microarray analysis and a high-throughput real-time RT-PCR approach using bone marrow-derived macrophages. Results: Within the originally identified Cdcs1-interval, three independent regions were detected that likely contain susceptibility-determining genetic factors (Cdcs1.1, Cdcs1.2, and Cdcs1.3). Combining results of candidate gene approaches revealed Fcgr1, Cnn3, Larp7, and Alpk1 as highly attractive candidate genes with polymorphisms in coding or regulatory regions and expression differences between susceptible and resistant mouse strains. Conclusions: Subcongenic analysis of the major susceptibility locus Cdcs1 on mouse chromosome 3 revealed a complex genetic structure. Candidate gene approaches revealed attractive genes within the identified regions with homologs that are located in human susceptibility regions for IBD.
Project description:IL-6 induces IL4ralpha expression in macrophages. This mechanism is necessary to promote macrophage polarization towards an M2-phenotype and is crucial to limit the inflammatory response both upon obesity and LPS-endotoxemia. In this dataset, we include the expression data obtained from primary murine bone marrow-derived macrophages from control and IL6ralpha-deficient macrophages (n=4vs4) stimulated with interleukin-6 (IL-6) 8 samples were analyzed to compare control and IL6ralpha-deficient macrophages for their gene expression profiles upon stimulation with IL-6
Project description:Interleukin-10 (IL-10) is a pleiotropic anti-inflammatory cytokine produced and sensed by most hematopoietic cells. Genome wide association studies and experimental animal models point at a central role of the IL-10 axis in Inflammatory Bowel Diseases. Here we investigated the importance of intestinal macrophage production of IL-10 and their IL-10 exposure, as well as the existence of an IL-10-based autocrine regulatory loop in the gut. Specifically, we generated mice harboring IL-10 or IL-10 receptor (IL-10R?) mutations in intestinal lamina propria-resident chemokine receptor CX3CR1hi-expressingmacrophages. We found macrophage-derived IL-10 dispensable for gut homeostasis and maintenance of colonic T regulatory cells. In contrast, loss of IL-10 receptor expression impaired the critical conditioning of these monocyte-derived macrophages, but resulted in spontaneous development of severe colitis. Collectively, our results highlight IL-10 as a critical homeostatic macrophage-conditioning factor in the colon and define intestinal CX3CR1hi macrophages as a decisive factor that determines gut health or inflammation. Microarray of resident macrophages sorted from colons of Interleukin-10 deficeint mice and macrophage-restricted interleukin-10 receptor deficient mice versus colonic resident macrophages of wild type mice
Project description:IL-6 induces IL4ralpha expression in macrophages. This mechanism is necessary to promote macrophage polarization towards an M2-phenotype and is crucial to limit the inflammatory response both upon obesity and LPS-endotoxemia. In this dataset, we include the expression data obtained from primary murine bone marrow-derived macrophages from control and IL6ralpha-deficient macrophages (n=4vs4) stimulated with interleukin-6 (IL-6)
Project description:We report the genome-wide RNA sequencing analysis in Il10-/- bone marrow-derived macrophages (BMDMs) stimulated by lipopolysaccharide (LPS) where IL-10 effect in macrophage inflammatory response was examined in IL-10-deficient BMDMs upon LPS stimulation with addition of exogenous IL-10.
Project description:Intestinal microbial dysbiosis is associated with Crohn’s disease (CD). However, the mechanisms leading to the chronic mucosal inflammation that characterizes this disease remain unclear. To evaluate causality and mechanisms of disease, we conducted a systems level study of the interactions between the gut microbiota and host in new-onset pediatric patients. We report an altered host proteome in CD patients indicative of impaired mitochondrial functions. A downregulation of mitochondrial proteins implicated in H2S detoxification was observed, while the relative abundance of H2S microbial producers was increased. Network correlation analysis identified Atopobium parvulum as the central hub of H2S producers. Gnotobiotic and conventionalized colitis-susceptible interleukin-10-deficient (Il10-/-) mice demonstrated that A. parvulum induced colitis, a phenotype requiring the presence of the intestinal microbiota. Administration of bismuth, a H2S scavenger, prevented A. parvulum-induced colitis in Il10-/- mice. This study identified host-microbiota interactions that are disturbed in CD patients providing mechanistic insights on CD pathogenesis.
Project description:Trichuris muris (T. muris) induces chronic colitis in susceptible mouse strains with clinical, histological, and immunological homology to human Crohn's disease. Gene expression profiling was performed on colon tissue of resistant (BALB/c) and susceptible (AKR) mice following T. muris infection.
Project description:Macrophages represent multifunctional leukocytes defined by their stimulus-specific transcriptional reprogramming. As in vivo macrophages are often difficult to obtain, in vitro macrophage models are often used. We aggregated public expression data to define consensus expression profiles for eight commonly-used in vitro macrophage models and built the classifier macIDR, capable of distinguishing macrophage subsets with high accuracy (>0.95). Classification of in vivo macrophages suggested that alveolar macrophages resembled interleukin-10 activated macrophages in general whereas chronic obstructive pulmonary disease patients displayed decreased similarity to interferon-γ stimulated macrophages. Adipose tissue-derived macrophages were classified as unstimulated macrophages, but would resemble LPS-stimulated macrophages more in diabetic-obese patients. Rheumatoid arthritic synovial macrophages were similar to macrophages stimulated with interleukin-10 or interferon-γ. Altogether, our results suggest that macIDR is capable of identifying in vitro macrophages. By projecting in vivo macrophages onto the in vitro macrophages, we were capable of elucidating macrophage-specific changes as a result of tissue and disease.