Project description:We used microRNA microarrays to identify dysregulated microRNAs in CD4+ T cells isolated from brains of EAE mice treated with vehicle or THC+CBD.
Project description:The present study had the purpose to analyze the transcriptional state of oligodendrocytes in an animal model of multiple scleroris resembling autoimmune neuroinflammation and compared with control mice treated with ovalbumin. The results revealed that oligodendrocytes from the EAE (experimental autoimmune encephalomyelitis) model upregulate genes that are involved in immune processes providing evidence that oligodendrocytes can develop an immune phenotype in particular neuroinflammatory conditions.
Project description:STAT5 plays a critical role in mediating cellular responses following cytokine stimulation. The activated STAT5 proteins can form dimers and tetramers with distinct biological functions. The role of STAT5 tetramerization in autoimmune-mediated neuroinflammation has not been investigated. Using the STAT5 tetramer-deficient Stat5a-Stat5b N-domain double knock-in (DKI) mouse strain, we report here that STAT5 tetramers promote the pathogenesis of experimental autoimmune encephalomyelitis (EAE). The mild EAE phenotype observed in DKI mice correlates with the impaired extravasation of pathogenic Th17 cells and interactions between Th17 cells and monocyte-derived cells (MDCs) in the meninges. We further demonstrated that STAT5 tetramerization regulates the GM-CSF-dependent production of CCL17 by MDCs. Importantly, DKI Th17 cells expanded with CCL17 exhibit more severe EAE. Mechanistically, the effect of CCL17 is dependent on the activity of the integrin VLA-4. Thus, our study uncovered a novel GM-CSF-STAT5 tetramer-CCL17 pathway that promotes autoimmune neuroinflammation via the regulation of Th17 cell migration.
Project description:Neuroinflammation causes neuronal injury in multiple sclerosis (MS) and other neurological diseases. MicroRNAs (miRNAs) are central modulators of cellular stress responses, but knowledge about miRNA–mRNA interactions that determine neuronal outcome during inflammation is limited. Here, we combined unbiased neuron-specific miRNA with mRNA sequencing to assemble the regulatory network that mediates robustness against neuroinflammation. As a critical miRNA-network hub we defined miR-92a. Genetic deletion of miR-92a exacerbated the disease course of mice undergoing experimental autoimmune encephalomyelitis (EAE), whereas miR-92a overexpression protected neurons against excitotoxicity. As a key miR-92a target transcript, we identified cytoplasmic polyadenylation element-binding protein 3 (Cpeb3) that was suppressed in inflamed neurons in mouse EAE and human MS. Accordingly, Cpeb3 deletion improved neuronal resistance to excitotoxicity and ameliorated EAE. Together, we discovered that the miR-92a–Cpeb3 axis confers neuronal robustness against inflammation and serves as potential target for neuroprotective therapies.
Project description:Neuroinflammation plays a role in the progression of several neurodegenerative disorders. We used a lipolysaccharide (LPS) model of neuroinflammation to characterize the gene expression changes underlying the inflammatory and behavioral effects of neuroinflammation. A single intracerebroventricular injection of LPS (5 ug) was administered into the lateral ventricle of mice and, 24 hours later, we examined gene expression in the cerebral cortex and hippocampus using microarray technology. Gene Ontology (GO) terms for inflammation and the ribosome were significantly enriched by LPS, whereas GO terms associated with learning and memory had decreased expression. We detected 224 changed transcripts in the cerebral cortex and 170 in the hippocampus. Expression of Egr1 (also known as Zif268) and Arc, two genes associated with learning and memory, was significantly lower in the cortex, but not hippocampus, of LPS-treated animals. Overall, altered expression of these genes may underlie some of the inflammatory and behavioral effects of neuroinflammation. Mice were given intracerebroventricular injections of saline vehicle (n = 4) or lipopolysaccharide (n = 4). Twenty-four hours later, we dissected the hippocampus and cerebral cortex and processed the tissue for microarray analysis. Gene expression changes observed in the microaray data were validated with quantitative real-time PCR.
Project description:Genes and pathways in which inactivation dampens tissue inflammation present new opportunities for understanding the pathogenesis of common human inflammatory diseases, including inflammatory bowel disease, rheumatoid arthritis and multiple sclerosis. We identified a mutation in the gene encoding the deubiquitination enzyme USP15 (Usp15L749R) that protected mice against both experimental cerebral malaria (ECM) induced by Plasmodium berghei and experimental autoimmune encephalomyelitis (EAE). Combining immunophenotyping and RNA sequencing in brain (ECM) and spinal cord (EAE) revealed that Usp15L749R-associated resistance to neuroinflammation was linked to dampened type I interferon responses in situ. In hematopoietic cells and in resident brain cells, USP15 was coexpressed with, and functionally acted together with the E3 ubiquitin ligase TRIM25 to positively regulate type I interferon responses and to promote pathogenesis during neuroinflammation. The USP15-TRIM25 dyad might be a potential target for intervention in acute or chronic states of neuroinflammation.
Project description:Genetic opticospinal EAE (OSE) and MOG-induced EAE (MOG-EAE) are two experimental autoimmune encephalomyelitis (EAE) mouse models of human multiple sclerosis. For the OSE model, double-transgenic 2D2 (TCRMOG) x IgHMOG mice were used. For MOG-EAE, wildtype C57BL/6 mice were immunized with a MOG peptide consisting of the amino acids 35-55, administered in complete Freund’s adjuvant containing 5mg / ml Mycobacterium tuberculosi. The severity of EAE was rated on the scale 0: healthy animal; 1: animal with a flaccid tail; [...]; 4: animal with both hind legs paralyzed. The case groups in the experiment were: OSE1: OSE with disease score 1; OSE4: OSE with disease score 4; MOG4: MOG-EAE injected with both MOG and adjuvant, with disease score 4. The control groups in the experiment were: OSE0: OSE with disease score 0; CFA: C57BL/6 mice injected only with adjuvant (no MOG); WT: Wildtype C57BL/6 mice. The aim of the experiment was to assess gene expression differences 1) between OSE4 and OSE0, 2) between OSE1 and OSE0, and 3) between MOG4 and CFA. For control, WT was compared to OSE0 and CFA. Subsequently, differentially expressed transcripts were compared, first, between the OSE4 vs. OSE0 and the MOG4 vs. CFA contrasts (different EAE models) and, second, between the OSE4 vs. OSE0 and the OSE1 vs. OSE0 contrasts (different EAE severity).