La venda d'animals a la Rambla de Barcelona

Treball presentat a la Facultat de Veterinària de la Universitat Autònoma de Barcelona.Treball presentat a l'assignatura de Deontologia i Veterinària Legal (21223

Engrailed 1 coordinates cytoskeletal reorganization to induce myofibroblast differentiation

Transforming growth factor-β (TGFβ) is a key mediator of fibroblast activation in fibrotic diseases, including systemic sclerosis. Here we show that Engrailed 1 (EN1) is reexpressed in multiple fibroblast subpopulations in the skin of SSc patients. We characterize EN1 as a molecular amplifier of TGFβ signaling in myofibroblast differentiation: TGFβ induces EN1 expression in a SMAD3-dependent manner, and in turn, EN1 mediates the profibrotic effects of TGFβ. RNA sequencing demonstrates that EN1 induces a profibrotic gene expression profile functionally related to cytoskeleton organization and ROCK activation. EN1 regulates gene expression by modulating the activity of SP1 and other SP transcription factors, as confirmed by ChIP-seq experiments for EN1 and SP1. Functional experiments confirm the coordinating role of EN1 on ROCK activity and the reorganization of cytoskeleton during myofibroblast differentiation, in both standard fibroblast culture systems and in vitro skin models. Consistently, mice with fibroblast-specific knockout of En1 demonstrate impaired fibroblast-to-myofibroblast transition and are partially protected from experimental skin fibrosis

Combined inhibition of IL-1, IL-33 and IL-36 signalling by targeting IL1RAP ameliorates skin and lung fibrosis in preclinical models of systemic sclerosis

BackgroundThe interleukin (IL)-1 receptor accessory protein (IL1RAP) is an essential coreceptor required for signalling through the IL-1, IL-33 and IL-36 receptors. Here, we investigate the antifibrotic potential of the combined inhibition of these cytokines by an anti-IL1RAP antibody to provide a scientific background for clinical development in systemic sclerosis (SSc).MethodsThe expression of IL1RAP-associated signalling molecules was determined by data mining of publicly available RNA sequencing (RNAseq) data as well as by imaging mass cytometry. The efficacy of therapeutic dosing of anti-IL1RAP antibodies was determined in three complementary mouse models: sclerodermatous chronic graft-versus-host disease (cGvHD), bleomycin-induced dermal fibrosis model and topoisomerase-I (topo)-induced fibrosis.ResultsSSc skin showed upregulation of IL1RAP and IL1RAP-related signalling molecules on mRNA and protein level compared with normal skin. IL-1, IL-33 and IL-36 all regulate distinct gene sets related to different pathophysiological processes in SSc. The responses of human fibroblasts and endothelial cells to IL-1, IL-33 and IL-36 were completely blocked by treatment with an anti-IL1RAP antibody in vitro. Moreover, anti-IL1RAP antibody treatment reduced dermal and pulmonary fibrosis in cGvHD-induced, bleomycin-induced and topoisomerase-induced fibrosis. Importantly, RNAseq analyses revealed effects of IL1RAP inhibition on multiple processes related to inflammation and fibrosis that are also deregulated in human SSc skin.ConclusionThis study provides the first evidence for the therapeutic benefits of targeting IL1RAP in SSc. Our findings have high translational potential as the anti-IL1RAP antibody CAN10 has recently entered a phase one clinical trial.http://dx.doi.org/10.13039/501100001659Deutsche ForschungsgemeinschaftTR221Ernst Jung FoundationElan-Foundation ErlangenFederal Ministry of Education and Research (BMBF)German Research Foundatio

Multi-omics characterization of fibroblasts and other stromal cells during progression and resolution of fibrotic tissue remodeling

Fibrosis refers to an excessive deposition of connective tissue and extracellular matrix (ECM) in response to injury. Fibrosis can virtually affect any organ. The ECM accumulation damages the structure and function of the affected tissue, commonly leading to organ malfunction and or even death. Prototypical fibrotic disorders include Systemic sclerosis (SSc), Idiophatic pulmonary fibrosis (IPF) and liver fibrosis. The pathogenesis of the fibrotic disorders can be divided in three major steps: 1) initial injury; 2) type II biased inflammatory response; 3) fibroblast activation, myofibroblast differentiation, ECM accumulation and fibrosis. Myofibroblasts, a cell type accumulating in fibrotic disorders, have been identified as the main cell type secreting the accumulating ECM proteins. In this study, we present a new single-cell multi-omics approach combining mass cytometry (CyTOF), single-cell RNA sequencing (scRNAseq) and imaging mass cytometry (IMC) that allows a deep phenotyping of stromal cells. We have analyzed murine liver and lung samples as well as human SSc skin and liver fibrosis. We identified new stromal cells subsets such as pro-fibrotic Sca1+/PI16+ fibroblasts shared between organs and liver-specific anti-fibrotic FAP+Cdh11+ fibroblasts. Moreover, we studied differences in the precursor cells of myofibroblasts in murine lung and liver and human skin and liver. In lung and skin, the myofibroblast pool is very heterogeneic: in the lung the dominant source of myofibroblasts are lipofibroblasts followed by pericytes, Sca1+ fibroblasts and arterial endothelial cells; in the skin, the most relevant source is the PI16+ fibroblasts, followed by pericytes and Podoplanin+ or FAP+ fibroblasts. In contrast, liver myofibroblasts are in more than 80% derived from hepatic stellate cells. In summary, this study presents a new approach to study the cellular changes and to deeply phenotype cellular heterogeneity. We also deconvolute the stromal cell compartments and sources of myofibroblasts origins across different states of fibrotic manifestation, including progression and resolution. These findings may not only improve our understanding of myofibroblast turnover, but may offer also new therapeutic venues with specific targeting of individual fibroblast subsets

La venda d'animals a la Rambla de Barcelona

Treball presentat a la Facultat de Veterinària de la Universitat Autònoma de Barcelona.Treball presentat a l'assignatura de Deontologia i Veterinària Legal (21223