Project description:Nephritis (LN) is a serious manifestation of SLE. Therapeutic studies in mouse LN models do not always predict outcomes of human therapeutic trials, raising concerns about the human relevance of these models. In this study we used an unbiased transcriptional network approach to define similarities and differences between three lupus models and human LN. Affymetrix-based expression profiles were analyzed using Genomatix Bibliosphere software and transcriptional networks were compared using the Tool for Approximate LargE graph matching (TALE). The 20 network hubs (nodes) shared between all three models and human LN reflect key pathologic processes, namely immune cell infiltration/activation, macrophage/dendritic cell activation, endothelial cell activation/injury and tissue remodeling/fibrosis. Each model also shares unique features with human LN. Pathway analysis of the TALE nodes highlighted macrophage/DC activation as a cross-species shared feature. To distinguish which genes and activation pathways might derive from mononuclear phagocytes in the human kidneys the gene expression profile of isolated NZB/W renal mononuclear cells was compared with human LN kidney profiles. Network analysis of the shared signature highlighted NFkappaB1 and PPARgamma as major hubs in the tubulointerstitial and glomerular networks respectively. Key nodes in the renal macrophage inflammatory response form the basis for further mechanistic and therapeutic studies. We used microarrays to analyze the transcriptome of microdissected renal biopsies from patients with lupus nephritis (LN) RNA from glomeruli and tubulointerstitial compartments was extracted and processed for hybridization on Affymetrix microarrays.
Project description:Nephritis (LN) is a serious manifestation of SLE. Therapeutic studies in mouse LN models do not always predict outcomes of human therapeutic trials, raising concerns about the human relevance of these models. In this study we used an unbiased transcriptional network approach to define similarities and differences between three lupus models and human LN. Affymetrix-based expression profiles were analyzed using Genomatix Bibliosphere software and transcriptional networks were compared using the Tool for Approximate LargE graph matching (TALE). The 20 network hubs (nodes) shared between all three models and human LN reflect key pathologic processes, namely immune cell infiltration/activation, macrophage/dendritic cell activation, endothelial cell activation/injury and tissue remodeling/fibrosis. Each model also shares unique features with human LN. Pathway analysis of the TALE nodes highlighted macrophage/DC activation as a cross-species shared feature. To distinguish which genes and activation pathways might derive from mononuclear phagocytes in the human kidneys the gene expression profile of isolated NZB/W renal mononuclear cells was compared with human LN kidney profiles. Network analysis of the shared signature highlighted NFkappaB1 and PPARgamma as major hubs in the tubulointerstitial and glomerular networks respectively. Key nodes in the renal macrophage inflammatory response form the basis for further mechanistic and therapeutic studies. We used microarrays to analyze the renal transcriptome of three different lupus mouse models, at early stage of lupus and during lupus nephritis. RNA from whole kidneys was extracted and processed for hybridization on Affymetrix microarrays.
Project description:Nephritis (LN) is a serious manifestation of SLE. Therapeutic studies in mouse LN models do not always predict outcomes of human therapeutic trials, raising concerns about the human relevance of these models. In this study we used an unbiased transcriptional network approach to define similarities and differences between three lupus models and human LN. Affymetrix-based expression profiles were analyzed using Genomatix Bibliosphere software and transcriptional networks were compared using the Tool for Approximate LargE graph matching (TALE). The 20 network hubs (nodes) shared between all three models and human LN reflect key pathologic processes, namely immune cell infiltration/activation, macrophage/dendritic cell activation, endothelial cell activation/injury and tissue remodeling/fibrosis. Each model also shares unique features with human LN. Pathway analysis of the TALE nodes highlighted macrophage/DC activation as a cross-species shared feature. To distinguish which genes and activation pathways might derive from mononuclear phagocytes in the human kidneys the gene expression profile of isolated NZB/W renal mononuclear cells was compared with human LN kidney profiles. Network analysis of the shared signature highlighted NFkappaB1 and PPARgamma as major hubs in the tubulointerstitial and glomerular networks respectively. Key nodes in the renal macrophage inflammatory response form the basis for further mechanistic and therapeutic studies. We used microarrays to analyze the renal transcriptome of three different lupus mouse models, at early stage of lupus and during lupus nephritis.
Project description:Nephritis (LN) is a serious manifestation of SLE. Therapeutic studies in mouse LN models do not always predict outcomes of human therapeutic trials, raising concerns about the human relevance of these models. In this study we used an unbiased transcriptional network approach to define similarities and differences between three lupus models and human LN. Affymetrix-based expression profiles were analyzed using Genomatix Bibliosphere software and transcriptional networks were compared using the Tool for Approximate LargE graph matching (TALE). The 20 network hubs (nodes) shared between all three models and human LN reflect key pathologic processes, namely immune cell infiltration/activation, macrophage/dendritic cell activation, endothelial cell activation/injury and tissue remodeling/fibrosis. Each model also shares unique features with human LN. Pathway analysis of the TALE nodes highlighted macrophage/DC activation as a cross-species shared feature. To distinguish which genes and activation pathways might derive from mononuclear phagocytes in the human kidneys the gene expression profile of isolated NZB/W renal mononuclear cells was compared with human LN kidney profiles. Network analysis of the shared signature highlighted NFkappaB1 and PPARgamma as major hubs in the tubulointerstitial and glomerular networks respectively. Key nodes in the renal macrophage inflammatory response form the basis for further mechanistic and therapeutic studies. We used microarrays to analyze the transcriptome of microdissected renal biopsies from patients with lupus nephritis (LN)
Project description:We defined the shared and unique features of systemic lupus erythematosus (SLE) nephritis in 2 mouse models of proliferative renal disease. We identified shared inflammatory mechanisms of SLE nephritis that can be therapeutically targeted. Some common mechanisms are shared with non-immune-mediated renal diseases, suggesting that new strategies to prevent tissue hypoxia and remodeling may be useful in SLE nephritis.
Project description:Lupus nephritis is a serious complication of systemic lupus erythematosus, mediated by IgG immune complex (IC) deposition in kidneys, with limited treatment options. Kidney macrophages are critical tissue sentinels that express IgG-binding Fcγ receptors (FcγRs), with previous studies identifying prenatally seeded resident macrophages as major IC responders. Using single-cell transcriptomic and spatial analyses in murine and human lupus nephritis, we sought to understand macrophage heterogeneity and subset-specific contributions in disease. In lupus nephritis, the cell fate trajectories of tissue-resident (TrMac) and monocyte-derived (MoMac) kidney macrophages were perturbed, with disease-associated transcriptional states indicating distinct pathogenic roles for TrMac and MoMac subsets. Lupus nephritis–associated MoMac subsets showed marked induction of FcγR response genes, avidly internalized circulating ICs, and presented IC-opsonized antigen. In contrast, lupus nephritis-associated TrMac subsets demonstrated limited IC uptake, but expressed monocyte chemoattractants, and their depletion attenuated monocyte recruitment to the kidney. TrMacs also produced B cell tissue niche factors, suggesting a role in supporting autoantibody-producing lymphoid aggregates. Extensive similarities were observed with human kidney macrophages, revealing cross-species transcriptional disruption in lupus nephritis. Overall, our study suggests a division of labor in the kidney macrophage response in lupus nephritis, with treatment implications — TrMacs orchestrate leukocyte recruitment while MoMacs take up and present IC antigen.
Project description:Systemic lupus erythematosus is a remitting relapsing autoimmune disease characterized by autoantibody production and multi-organ involvement. T cell epigenetic dysregulation plays an important role in the pathogenesis of lupus. We have previously demonstrated upregulation of the key epigenetic regulator EZH2 in CD4+ T cells isolated from lupus patients. To further investigate the role of EZH2 in the pathogenesis of lupus, we generated a tamoxifen-inducible CD4+ T cell Ezh2 conditional knockout mouse on the MRL/lpr lupus-prone background. We demonstrate that Ezh2 deletion abrogates lupus-like disease and prevents T cell differentiation. Single-cell analysis suggests impaired T cell function and activation of programed cell death pathways in EZH2-deficient mice. Ezh2 deletion in CD4+ T cells restricts TCR clonal repertoire and prevents kidney-infiltrating effector CD4+ T cell expansion and tubulointerstitial nephritis, which has been linked to end-stage renal disease in patients with lupus nephritis.
Project description:We profiled manually microdissected tubulointerstitial tissue from 43 IgA nephropathy, 3 diabetes mellitus nephropathy, 3 focal segmental glomerulosclerosis, 3 lupus nephritis, 4 membranous nephropathy, and 9 minimal change disease biopsy cores and 22 nephrectomy controls by RNA sequencing. The 3 outliers which were not included in our main analysis were also uploaded in this database.