Project description:Inflammation of epithelial structures frequently leads to disease at distal organs, but the mechanism responsible for this is unknown. We report evidence that digestion of hyaluronan in the extracellular matrix signals distal stromal cells to become primed for increased inflammation. By applying transgenic mouse models and single cell RNA sequencing of mouse and human tissues we demonstrate that skin injury or infection promotes an adipogenic response in distinct populations of distant submucosal fibroblasts of the colon. This response can be recapitulated without skin inflammation by expression of hyaluronidase in skin that promotes a highly amplified and frequently fatal host response to intestinal injury. Our results uncover an innate system of communication between epithelial stroma that is not initiated by immunocyte trafficking or cytokine signaling.
Project description:Inflammation of epithelial structures frequently leads to disease at distal organs, but the mechanism responsible for this is unknown. We report evidence that digestion of hyaluronan in the extracellular matrix signals distal stromal cells to become primed for increased inflammation. By applying transgenic mouse models and single cell RNA sequencing of mouse and human tissues we demonstrate that skin injury or infection promotes an adipogenic response in distinct populations of distant submucosal fibroblasts of the colon. This response can be recapitulated without skin inflammation by expression of hyaluronidase in skin that promotes a highly amplified and frequently fatal host response to intestinal injury. Our results uncover an innate system of communication between epithelial stroma that is not initiated by immunocyte trafficking or cytokine signaling.
Project description:In the present study, we analyzed single-cell multi-omics data from psoriasis patients and healthy individuals and found that more fibroblast-macrophage communication was present in the dermis of psoriasis lesions, exacerbating psoriasis progression. A natural product library was used to screen for a small molecule compound, celastrol, that could interfere with fibroblast-macrophage communication. It was demonstrated that celastrol targeted low-denisity lipoprotein receptor-related protein 1 (LRP1) to inhibit fibroblast secretion of CCL2 and inhibited psoriasis progression by reducing its recruitment to macrophages, thereby blocking communication between the two cells. Moreover, conditional knockdown of LRP1 by fibroblasts significantly improved psoriasis in mice, suggesting that LRP1 may be an important target for the treatment of psoriasis.
Project description:Single-cell RNA sequencing (scRNA-seq) was performed to investigate fibroblast–myeloid cell crosstalk in lung fibrosis. The dataset includes murine lung macrophage–fibroblast cocultures or fibroblast monocultures, with macrophages derived from WT mice and fibroblasts from either WT or fibroblast-specific P2rx4 knockout (Pdgfrb-Cre: P2rx4 f/f) mice 7 days after bleomycin injury. Cells were captured using the Fluent Biosciences PIPseq platform. Data include gene–cell count matrices and support the study “Myeloid–mesenchymal crosstalk drives ARG1-dependent profibrotic metabolism via ornithine in lung fibrosis” (Yadav et al., 2025).
Project description:Investigation of the role of hyaluronan in cardiomyocytes . The aims of the study were to determine if cardiomyocytes are capable of detecting hyaluronan and if then intrecellular signaling causes changes in gene expression. The study showed that cardiomyocytes can bind hyaluronan with following change in gene expression.
Project description:Background: Myocardial infarction (MI) and subsequent ischaemic cardiomyopathy (ICM) are the primary causes of heart failure. Inter-α trypsin inhibitor heavy chain 5 (ITIH5) is an ECM protein and has been identified as a myocardial marker of ICM. However, its diagnostic value in patients with ICM and its function and molecular mechanism in regulating cardiac repair and remodelling after MI remain unknown. Methods: Three microarray datasets including 117 ICM and 152 non-failing (NF) myocardial tissue samples were merged and analysed. Peripheral blood and clinical information were collected from 53 patients with ICM and 40 NF controls. The effects of ITIH5 on cellular interactions and cardiac remodelling was studied using ITIH5 RNAi adeno-associated virus and mouse MI model in vivo and in fibroblast–macrophage co-culture model in vitro. Results: ITIH5 was upregulated in the myocardial tissue and peripheral blood of patients with ICM and could be an independent risk factor for ICM. Experiments in mice suggested that ITIH5 promotes cardiac fibrotic remodelling at all phases after MI. Downregulation of ITIH5 increased the risk of death within 7 d after MI but inhibited ventricular remodelling and improved cardiac function on the long-term. ITIH5 promotes the primary cardiac fibroblasts (CFs) proliferation, migration, and improves survival rather than activiation. Morover, ITIH5 directly promotes macrophage tissue infiltration, maturation, and profibrotic phenotype transformation, thereby promoting fibrotic remodelling. By using fibroblast–macrophage co-culture model, we demonstrated ITIH5 enhanced the fibroblast/macrophage crosstalk manifest as macrophage profibrotic phenotype transformation and CFs activation, mainly by enhancing the hyaluronan stability, the ability of ITIH5 to bind macrophage CD44 receptors and the downstream activation of the signal transduction and activator of transcription 3 pathway in macrophages. Conclusions: ITIH5 could be used as a diagnostic marker for ICM. Moreover, ITIH5 expression was upregulated after MI, which accelerated ECM-fibroblast-macrophage interaction, thereby promoting macrophage profibrotic phenotype transformation, CFs activation, and cardiac fibrotic remodelling.