Maresin-1 promotes neuroprotection in relapsing remitting mouse model of multiple sclerosis
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ABSTRACT: Multiple sclerosis (MS) is a prevalent inflammatory neurodegenerative disease in young people, causing neurological abnormalities and impairment. We investigated the effect of maresin 1 (MaR1) on the progression of disease in relapsing remitting form of experimental autoimmune encephalomyelitis (RR-EAE). Treatment with MaR1 in RR-EAE accelerated inflammation resolution, protected against neurological impairments, and delayed disease development by reducing immune cell infiltration (CD4+IL17+ and CD4+IFNg+) into the CNS. Furthermore, injection of MaR1 enhanced IL-10 production, primarily in macrophages and CD4+ cells. However, neutralizing IL-10 with an anti-IL-10 antibody eliminated MaR1's protective impact on RR-EAE, implying that IL-10 plays a role in MaR1's EAE protection. Metabolism is increasingly being recognized as a critical element controlling the effector activity of many immune cells. Our investigation found that, when compared to vehicle treatment, MaR1 administration significantly repaired the metabolic dysregulation seen in CD4+ cells, macrophages, and microglia in the treated group. Furthermore, MaR1 treatment restored defective efferocytosis in EAE mice, which was potentially facilitated by the induction of metabolic alterations in macrophages and microglia. MaR1 also preserved myelin in the EAE group and regulated O4+ oligodendrocyte metabolism by reversing metabolic dysregulation via increased mitochondrial activity and decreased glycolysis. Overall, in a preclinical MS animal model, MaR1 therapy has anti-inflammatory and neuroprotective properties. It also induced metabolic reprogramming in disease-associated cell types, increased efferocytosis, and maintained myelination. These findings suggest MaR1's potential as a novel therapeutic agent for MS and other autoimmune diseases
Project description:The immunomodulatory cellular network that triggers early inflammation and demyelination, the key steps in multiple sclerosis (MS) pathogenesis remains poorly characterized. Here, we demonstrate that overactivation of the Wnt pathway promotes pathological transformation of oligodendrocyte precursor cells (OPCs) to replicate pathological OPCs in human MS. In mouse experimental autoimmune encephalomyelitis (EAE), pathological OPCs attract CD4+ T-helper 1 (Th1) cells into the spinal cord and the brain through CC-chemokine ligand 4 (CCL4). Th1 cells cooperate with OPCs inducing subpopulation of cytotoxic macrophages that execute early demyelination. Simultaneously, Th1 cells and cytotoxic macrophages upregulate Wnt signaling and CCL4 expression in OPCs, thus exerting positive feedback onto the OPC-immune cascade and establishing a vicious cycle propagating EAE pathogenesis. Breaking this cascade by targeting CCL4 reduces immune cell infiltration, alleviates demyelination, and attenuates EAE severity. Our findings demonstrate a closely coordinated network of OPCs and immune cells therefore providing an alternative insight into MS pathophysiology
Project description:Malignant Pleural Effusion (MPE) results from the capacity of several human cancers to metastasize to the pleural cavity. The median survival is 3-12 months and no effective treatments are currently available. Immune-based therapies have failed until now, reflecting our insufficient understanding of the basic immunological mechanisms leading to MPE progression. Here, we show that phagocytosis of apoptotic cells in the pleural cavity fuels the progression of MPE. We found that efferocytosis through the receptor tyrosine kinases AXL and MERTK in macrophages led to the production of IL-10. Using single cell RNA-Seq, we revealed that IL-10 is indeed produced by four distinct pleural cavity macrophage subpopulations characterized by different metabolic states and cell chemotaxis properties. In turn, IL-10 acts on dendritic cells (DCs) inducing the production of tissue inhibitor of metalloproteinases 1 (TIMP1). Genetic ablation of AXL and MERTK in macrophages or IL-10 receptor in DCs or TIMP1 significantly reduced MPE progression. Taken together, our results delineate an inflammatory cascade – from the clearance of apoptotic cells by macrophages, to production of IL-10, to induction of TIMP1 in DCs – that facilitates MPE progression. This inflammatory cascade offers a series of targets for therapies which aim at preventing or treating MPE.
Project description:The objective of this study is to examine IL-11-induced mechanisms of inflammatory cell migration to the CNS. We report that IL-11 is produced at highest frequency by myeloid cells among the PBMC cell subsets. Patients with relapsing-remitting multiple sclerosis (RRMS) have an increased frequency of IL-11+ monocytes, IL-11+ and IL-11R+ CD4+ lymphocytes and IL-11R+ neutrophils in comparison to matched healthy controls (HCs). IL-11+ and GM-CSF+ monocytes, CD4+ lymphocytes, and neutrophils accumulate in the cerebrospinal fluid (CSF). The effect of IL-11 in-vitro stimulation, examined using single cell RNA sequencing (scRNAseq), revealed the highest number of differentially expressed genes (DEGs) in classical monocytes, including upregulated NFKB1, NLRP3 and IL1B. All CD4+ cell subsets had increased expression of S100A8/9 alarmin genes involved in NLRP3 inflammasome activation. In IL-11R+-sorted cells from the CSF, classical and intermediate monocytes significantly upregulated the expression of multiple NLRP3 inflammasome-related genes, including complement, IL18, and migratory genes (VEGFA/B) in comparison to blood-derived cells. Therapeutic targeting of this pathway with aIL-11 mAb in mice with RR experimental autoimmune encephalomyelitis (EAE) decreased clinical scores, CNS inflammatory infiltrates and demyelination. aIL-11 mAb treatment decreased the numbers of NFkBp65+, NLRP3+ and IL-1b+ monocytes in the CNS of mice with EAE. The results suggest that IL-11/IL-11R signaling in monocytes represents a therapeutic target in RRMS.
Project description:MicroRNAs are small non-coding RNA molecules that have an important role in the fine tuning of all biological processes and are often found to be dysregulated in diseases, such as multiple sclerosis (MS). MS is an immune-mediated disease of the central nervous system characterized by demyelination, axonal loss and neurodegeneration. We have previously shown microRNA-150 (miR-150) levels to be elevated in cell-free cerebrospinal fluid (CSF) of MS patients compared to controls. The aim of this study is to further understand the physiopathological function of miR-150 using experimental autoimmune encephalomyelitis (EAE), a mouse model for MS. To establish its role in-vivo, we generated miR-150 knock-out (KO) and knock-in (KI) mice using CRISPR/Cas9. After induction of EAE, miR-150 KO mice showed ameliorated disease compared to WT littermate controls while miR-150 KI mice presented with exacerbated disease. An ameliorated disease in miR-150 KO was accompanied by a decreased infiltration of CD4 T cells compared to WT and KI. At priming stage of EAE we found that miR-150 KO had an increase in regulatory CD4 T cells (TREGS). Furthermore, after reconstitution of T cell deficient animals, CD4 T cells from miR-150 KO mice could protect against EAE and also showed an increased FOXP3 expression. A role of miR-150 in regulating TREG cells was further substantiated by transcriptome profiling, where miR-150 KO CD4 T cells suggested an enhancement of TREG phenotype as well as a diminished translation in miR-150 KO CD4 T cells. Moreover the results implicated miR-150 with mechanisms such as translation, autophagy and metabolism as well T cell proliferation and differentiation. In conclusion, miR-150 deficiency favored a more anti-inflammatory environment while miR-150 expression promoted pathogenic CD4 T cells subsets, potentially associated with metabolic mechanisms.
Project description:Our results introduce interleukin (IL)-11 as a new cytokine that may play a role in the development of the autoimmune response in patients with relapsing remitting multiple sclerosis (RR MS). IL-11 was found to be the highest up-regulated cytokine in the serum and cerebrospinal fluid (CSF) from patients with clinically isolated syndrome (CIS) suggestive of MS. It was also increased in the serum and CSF of patients with clinically definitive RRMS and during the clinical relapses of the disease. CD4+ cells represent a predominant cell source of IL-11 in the peripheral circulation, and the percentage of IL-11+CD4+ cells is significantly increased in CIS patients in comparison to healthy controls (HCs). Furthermore, we have identified IL-11 as a new Th17-promoting cytokine. IL-11 induces a differentiation of naïve CD4+ T cells into Th17 cells, as well as Th17 memory cell expansion, characterized by secretion of IL-17A, IL-17F, IL-21 and IL-22. Since the Th17 cytokines IL-17F, IL-21 and TNF- induced differentiation of naïve cells in the IL-11-secreting CD4+ cells, we propose that cross-talk between IL-11+CD4+ and Th17-cells may play a role in the initiation and propagation of the autoimmune response in RRMS. PBMCs were separated from 15 CIS patients and 7 HCs, and the total RNA was extracted and used for gene array hybridization as described previously. To detect differential gene expression profiles between the CIS patients and HCs, a two class paired test of significance analysis was used.
Project description:Microglia, the parenchymal brain macrophages of the central nervous system (CNS), have emerged as critical players in brain development and homeostasis. Immune functions of these cells, however, remain less well defined. We investigated contributions of microglia in a relapsing remitting (RR) multiple sclerosis paradigm, experimental autoimmune encephalitis (RR-EAE) in C57BL/6 / SJL F1 mice. Fate mapping-assisted translatome profiling during the RR disease course revealed the potential of microglia to interact with T cells through antigen presentation, co-stimulation, and co-inhibition. Abundant microglia - T cell aggregates, as observed by histology and flow cytometry, supported the notion of functional interactions of microglia and T cells during remission, with a bias towards T regulatory cells. Finally, microglia_x0002_restricted Ifng receptor and MHC mutagenesis significantly affected the functionality of the regulatory T cell compartment in the diseased CNS and remission. Collectively, our data establish critical non-redundant cognate and cytokine-mediated interactions of microglia with CD4+ T cells during autoimmune neuro-inflammation.
Project description:Defects in apoptotic cell clearance, or efferocytosis, can cause inflammatory diseases and prevent tissue repair due in part, to a key role of efferocytosis in inducing a pro-repair transcriptional program in phagocytic cells like macrophages. While the cellular machinery and metabolic pathways involved in efferocytosis have been characterized, the precise efferocytic response of macrophages is dependent on the identity and macromolecular cues of apoptotic cells, and the complex tissue microenvironment in which efferocytosis occurs. Here, we find that macrophages undergoing active efferocytosis in mid-stage mouse skin wounds in vivo display a pro-repair gene program, while efferocytosis of apoptotic skin fibroblasts in vitro induces an immature/inflammatory transcription response. These data provide a resource for understanding how the skin wound niche influences macrophage efferocytosis and will be useful for future investigations that define the role of efferocytosis during tissue repair
Project description:The signal transducer and activator of transcription 4 (STAT4) promotes protective immunity and autoimmunity downstream of pro-inflammatory cytokines including IL-12 and IL-23. In experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS), Stat4-/- mice are resistant to the development of inflammation and paralysis. Here, we examined cell-type requirements and found that in addition to T cells, STAT4 is required in dendritic cells for development of EAE. Deficiency of STAT4 in CD11c-expressing cells resulted in decreased T cell priming and inflammation in the CNS. EAE susceptibility was recovered following adoptive transfer of wild type bone marrow-derived DC to mice with STAT4-deficient DCs, but not adoptive transfer of STAT4- or IL-23R-deficient DCs. Single cell RNA-seq identified STAT4-dependent genes in DC subsets that paralleled a signature in MS patient DCs. Together, these data define a novel IL-23/DC/STAT4 pathway in DCs that could be a key to novel therapeutic targets in MS.
Project description:This file contains gene microarray data from FACS purified mouse memory phenotype CD4+ T cells (CD44hiCD45RBloCD25-), which were isolated from lymph node and spinal cord tissues of mice with experimental autoimmune encephalomyelitis (EAE), a widely studied model of human multiple sclerosis (MS). Memory phenotype CD4+ T cells infiltrating the CNS during EAE expressed high levels of mRNA for Dgat1 encoding diacylglycerol-O-acyltransferase-1 (DGAT1). We studied the biology of DGAT1 in EAE models and in assays of T cell differentiation and function.
Project description:Severe carbon monoxide (CO) poisoning can cause structural damage to the nervous system, leading to long-term cognitive dysfunction in patients. Correctly terminating the inflammatory response caused by neuronal damage is a prerequisite for tissue repair. Macrophages can clear the cell corpses/fragments caused by brain injury through efferocytosis, and produce cytokines to coordinate the immune response, promoting neuronal repair and regeneration. However, in the microenvironment of the nervous system affected by CO poisoning, the function of macrophages is inhibited. Our research found that CLCF1 can regulate the secretion of cytokines such as TNF-α, IL-1β, and IL-10 through the NF-κB signaling pathway, thereby affecting neural cell repair and regeneration. Simultaneously, CLCF1 can regulate the efferocytosis function of macrophages, thus controlling the degree of inflammation and assisting in the repair of the damaged nervous system. In experiments, it was observed that targeting the regulation of macrophage CLCF1 expression led to improvements in memory, learning, and motor abilities in rats poisoned with CO.