The outcome of cancer and autoimmunity is often dictated by the effector functions of CD4+ conventional T cells (Tconv). Although activation of the NF-κB signaling pathway has long been implicated in Tconv biology, the cell-autonomous roles of the separate NF-κB transcription-factor subunits are unknown. Here, we dissected the contributions of the canonical NF-κB subunits RelA and c-Rel to Tconv function.
View Article and Find Full Text PDFSince the Nobel Prize award more than twenty years ago for discovering the core apoptotic pathway in , apoptosis and various other forms of regulated cell death have been thoroughly characterized by researchers around the world. Although many aspects of regulated cell death still remain to be elucidated in specific cell subtypes and disease conditions, many predicted that research into cell death was inexorably reaching a plateau. However, this was not the case since the last decade saw a multitude of cell death modalities being described, while harnessing their therapeutic potential reached clinical use in certain cases.
View Article and Find Full Text PDFParkinson's disease (PD) is a neurodegenerative disorder characterized by alpha-synuclein (αSyn) aggregation and associated with abnormalities in lipid metabolism. The accumulation of lipids in cytoplasmic organelles called lipid droplets (LDs) was observed in cellular models of PD. To investigate the pathophysiological consequences of interactions between αSyn and proteins that regulate the homeostasis of LDs, we used a transgenic Drosophila model of PD, in which human αSyn is specifically expressed in photoreceptor neurons.
View Article and Find Full Text PDFParkinson's disease (PD) is characterized by the progressive accumulation of neuronal intracellular aggregates largely composed of alpha-Synuclein (αSyn) protein. The process of αSyn aggregation is induced during aging and enhanced by environmental stresses, such as the exposure to pesticides. Paraquat (PQ) is an herbicide which has been widely used in agriculture and associated with PD.
View Article and Find Full Text PDFGlial cells are early sensors of neuronal injury and can store lipids in lipid droplets under oxidative stress conditions. Here, we investigated the functions of the RNA-binding protein, SPEN/SHARP, in the context of Parkinson's disease (PD). Using a data-mining approach, we found that SPEN/SHARP is one of many astrocyte-expressed genes that are significantly differentially expressed in the substantia nigra of PD patients compared with control subjects.
View Article and Find Full Text PDFBackground: Many older community-dwelling subjects may be frail and/or disoriented, putting them at risk of adverse outcomes. We investigated the prevalence of frailty and spatiotemporal disorientation among patients aged > 65 years collecting regular medication at a community pharmacy.
Methods: Prospective, cross-sectional study of geriatric evaluation in 218 community pharmacies in France.
Objectives: This study aims to: (i) quantify the number of pharmaceutical interventions (PIs) linked to spontaneous requests for the two oral target molecules, ibuprofen and pseudoephedrine (ii) analyse the causes and proposed solutions (iii) quantify the number of registrations in the patient's pharmaceutical record and identify the various causes of non-registration.
Methods: The study was conducted over a 2 weeks' period in the months of February and April 2014 in 482 pharmacies affiliated to the training supervisor associations of 8 French Faculties of Pharmacy. Data regarding spontaneous requests for the target molecules was collected, with due respect to a patient care flow chart at the pharmacy, by incorporating the systematic proposal for registration of the medication in the patient's pharmaceutical record.
Multiple sclerosis (MS) is an auto-immune demyelinating disorder characterized by a chronic neuro-inflammatory process associated with an infiltration of the central nervous system (CNS) by autoreactive lymphocytes. The etiology of the disease remains unclear but the recent discovery of a dysregulated miRNA network in both cells and extracellular fluids of MS patients has brought new insights on the pathophysiological mechanisms involved in this disorder. miRNAs can induce a T cell polarization towards a pathological Th17 or Th1 phenotype and a deleterious activation of microglia, the CNS-resident macrophages.
View Article and Find Full Text PDFNew evidence has highlighted that miRNA production and trafficking can be dysregulated in both autoimmmune and neurological disorders. Multiple sclerosis (MS) in particular is an autoimmune pathology leading to neurodegeneration. Profiling studies performed on cells derived from MS patients have described a dysregulated network of miRNAs in both immune and neural cells.
View Article and Find Full Text PDFWe developed a Drosophila model in which the dengue virus NS3 protein is expressed in a tissue specific and inducible manner. Dengue virus NS3 is a multifunctional protein playing a major role during viral replication. Both protease and helicase domains of NS3 are interacting with human and insect host proteins including innate immune components of the host machinery.
View Article and Find Full Text PDFApoptosis is required during development to eliminate superfluous cells and sculpt tissues; spatial and timed control of apoptosis ensures that the necessary number of cells is eliminated at a precise time in a given tissue. The elimination of supernumerary pigment or inter-ommatidial cells (IOCs) depends on cell-cell communication and is necessary for the formation of the honeycomb-like structure of the Drosophila eye. However, the mechanisms occurring during pupal development and controlling apoptosis of superfluous IOC in space and time remain unclear.
View Article and Find Full Text PDFInfluenza A NS1 and NS2 proteins are encoded by the RNA segment 8 of the viral genome. NS1 is a multifunctional protein and a virulence factor while NS2 is involved in nuclear export of viral ribonucleoprotein complexes. A yeast two-hybrid screening strategy was used to identify host factors supporting NS1 and NS2 functions.
View Article and Find Full Text PDFMicroglial cells constitute the first line of defense of the central nervous system (CNS) against microbial invasion. Pathogens are detected thanks to an array of innate immune receptors termed pattern recognition receptors (PRRs). PRRs have been thoroughly characterized in bone marrow-derived macrophages, but the PRRs repertoire and functionality in microglial cells remain largely unknown.
View Article and Find Full Text PDFBackground: The genus Flavivirus encompasses more than 50 distinct species of arthropod-borne viruses, including several major human pathogens, such as West Nile virus, yellow fever virus, Japanese encephalitis virus and the four serotypes of dengue viruses (DENV type 1-4). Each year, flaviviruses cause more than 100 million infections worldwide, some of which lead to life-threatening conditions such as encephalitis or haemorrhagic fever. Among the viral proteins, NS3 and NS5 proteins constitute the major enzymatic components of the viral replication complex and are essential to the flavivirus life cycle.
View Article and Find Full Text PDFA proteome-wide mapping of interactions between hepatitis C virus (HCV) and human proteins was performed to provide a comprehensive view of the cellular infection. A total of 314 protein-protein interactions between HCV and human proteins was identified by yeast two-hybrid and 170 by literature mining. Integration of this data set into a reconstructed human interactome showed that cellular proteins interacting with HCV are enriched in highly central and interconnected proteins.
View Article and Find Full Text PDFMicroglia form a unique population of brain-resident macrophages. Although microglia have been involved in multiple disorders of the central nervous system (CNS), the issue of microglial renewal, under normal or pathological conditions, has been controversial. In mice, results from bone marrow chimera studies indicated that microglia are slowly but continuously replenished by bone marrow-derived cells.
View Article and Find Full Text PDFCannabinoids are potential agents for the development of therapeutic strategies against multiple sclerosis. Here we analyzed the role of the peripheral CB(2) cannabinoid receptor in the control of myeloid progenitor cell trafficking toward the inflamed spinal cord and their contribution to microglial activation in an animal model of multiple sclerosis (experimental autoimmune encephalomyelitis, EAE). CB(2) receptor knock-out mice showed an exacerbated clinical score of the disease when compared with their wild-type littermates, and this occurred in concert with extended axonal loss, T-lymphocyte (CD4(+)) infiltration, and microglial (CD11b(+)) activation.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
April 2008
Magnetic resonance imaging (MRI) of inflammation is based on the in vivo magnetic labelling of macrophages, the most abundant cells involved in the post-ischemic inflammatory response, by nanoparticles of iron oxides. Such approach has been successfully applied to study experimental rodent models of focal cerebral ischemia and has proved feasible in pioneer clinical studies. Despite current limitations, MRI of inflammation may become an important tool for the investigation of novel ischemic stroke therapeutics targeted at inflammation.
View Article and Find Full Text PDFBackground And Purpose: A growing body of evidence suggests that inflammatory processes are involved in the pathophysiology of stroke. Phagocyte cells, involving resident microglia and infiltrating macrophages, secrete both protective and toxic molecules and thus represent a potential therapeutic target. The aim of the present study was to monitor phagocytic activity after focal cerebral ischemia in mice.
View Article and Find Full Text PDFRecent evidence indicates that microglial cells may not derive from blood circulating mature monocytes as they express features of myeloid progenitors. Here, we observed that a subpopulation of microglial cells expressed CD34 and B220 antigens during brain development. We thus hypothesized that microglia, or a subset of microglial cells, originate from blood circulating CD34+/B220+ myeloid progenitors, which could target the brain under developmental or neuroinflammatory conditions.
View Article and Find Full Text PDFMeasles virus (MV) infection causes an acute childhood disease, associated in certain cases with infection of the central nervous system and development of a severe neurological disease. We have generated transgenic mice ubiquitously expressing the human protein SLAM (signaling lymphocytic activation molecule), or CD150, recently identified as an MV receptor. In contrast to all other MV receptor transgenic models described so far, in these mice infection with wild-type MV strains is highly pathogenic.
View Article and Find Full Text PDFThe semaphorin-signaling transducer collapsin response mediator protein 2 (CRMP2) has been identified in the nervous system where it mediates Sema3A-induced growth cone navigation. In the present study, we provide first evidence that CRMP2 is present in the immune system and plays a critical role in T lymphocyte function. CRMP2 redistribution at the uropod in polarized T cells, a structural support of lymphocyte motility, suggests that it may regulate T cell migration.
View Article and Find Full Text PDFThe lack of draining lymphatic vessels in the central nervous system (CNS) contributes to the so-called "CNS immune privilege." However, despite such a unique anatomic feature, dendritic cells (DCs) are able to migrate from the CNS to cervical lymph nodes through a yet unknown pathway. In this report, labeled bone marrow-derived myeloid DCs were injected stereotaxically into the cerebrospinal fluid (CSF) or brain parenchyma of normal rats.
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